Rate limiting reference
Arcjet rate limiting allows you to define rules which limit the number of requests a client can make over a period of time.
Configuration
Each rate limit is configured on an exact path with a set of client characteristics and algorithm specific options.
Fixed window rate limit options
Tracks the number of requests made by a client over a fixed time window. Options are explained in the Configuration documentation. See the fixed window algorithm description for more details about how the algorithm works.
// Options for fixed window rate limit// See https://docs.arcjet.com/rate-limiting/configurationtype FixedWindowRateLimitOptions = { // "LIVE" will block requests. "DRY_RUN" will log only mode?: "LIVE" | "DRY_RUN"; // How the client is identified. We recommend setting characteristics on the // Arcjet client rather than per rule. Global characteristics default to the // request IP characteristics?: string[]; // Time window the rate limit applies to window: string; // Maximum number of requests allowed in the time window max: number;};Fixed window example
import arcjet, { fixedWindow } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com rules: [ fixedWindow({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only window: "60s", // 60 second fixed window max: 100, // allow a maximum of 100 requests }), ],});import arcjet, { fixedWindow } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], // track requests by IP address rules: [ fixedWindow({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only window: "60s", // 60 second fixed window max: 100, // allow a maximum of 100 requests }), ],});import arcjet, { fixedWindow } from "@arcjet/node";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], // track requests by IP address rules: [ fixedWindow({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only window: "60s", // 60 second fixed window max: 100, // allow a maximum of 100 requests }), ],});import arcjet, { fixedWindow } from "@arcjet/sveltekit";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], // track requests by IP address rules: [ fixedWindow({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only window: "60s", // 60 second fixed window max: 100, // allow a maximum of 100 requests }), ],});Sliding window rate limit options
Tracks the number of requests made by a client over a sliding window so that the window moves with time. Options are explained in the Configuration documentation. See the sliding window algorithm description for more details about how the algorithm works.
// Options for sliding window rate limit// See https://docs.arcjet.com/rate-limiting/configurationtype SlidingWindowRateLimitOptions = { // "LIVE" will block requests. "DRY_RUN" will log only mode?: "LIVE" | "DRY_RUN"; // How the client is identified. We recommend setting characteristics on the // Arcjet client rather than per rule. Global characteristics default to the // request IP characteristics?: string[]; // The time interval in seconds for the rate limit interval: number; // Maximum number of requests allowed over the time interval max: number;};Sliding window example
import arcjet, { slidingWindow } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], // track requests by IP address rules: [ slidingWindow({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only interval: 60, // 60 second sliding window max: 100, // allow a maximum of 100 requests }), ],});import arcjet, { slidingWindow } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], // track requests by IP address rules: [ slidingWindow({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only interval: 60, // 60 second sliding window max: 100, // allow a maximum of 100 requests }), ],});import arcjet, { slidingWindow } from "@arcjet/node";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], // track requests by IP address rules: [ slidingWindow({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only interval: 60, // 60 second sliding window max: 100, // allow a maximum of 100 requests }), ],});import arcjet, { slidingWindow } from "@arcjet/sveltekit";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], // track requests by IP address rules: [ slidingWindow({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only interval: 60, // 60 second sliding window max: 100, // allow a maximum of 100 requests }), ],});Token bucket rate limit options
Based on a bucket filled with a specific number of tokens. Each request withdraws a token from the bucket and the bucket is refilled at a fixed rate. Once the bucket is empty, the client is blocked until the bucket refills. Options are explained in the Configuration documentation. See the token bucket algorithm description for more details about how the algorithm works.
// Options for token bucket rate limit// See https://docs.arcjet.com/rate-limiting/configurationtype TokenBucketRateLimitOptions = { // "LIVE" will block requests. "DRY_RUN" will log only mode?: "LIVE" | "DRY_RUN"; // How the client is identified. We recommend setting characteristics on the // Arcjet client rather than per rule. Global characteristics default to the // request IP characteristics?: string[]; // Number of tokens to add to the bucket at each interval refillRate: number; // The interval in seconds to add tokens to the bucket interval: number; // The maximum number of tokens the bucket can hold capacity: number;};Token bucket example
See the token bucket request example for how to specify the number of tokens to request.
import arcjet, { tokenBucket } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], // track requests by IP address rules: [ tokenBucket({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only refillRate: 10, // refill 10 tokens per interval interval: 60, // 60 second interval capacity: 100, // bucket maximum capacity of 100 tokens }), ],});import arcjet, { tokenBucket } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], // track requests by IP address rules: [ tokenBucket({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only refillRate: 10, // refill 10 tokens per interval interval: 60, // 60 second interval capacity: 100, // bucket maximum capacity of 100 tokens }), ],});import arcjet, { tokenBucket } from "@arcjet/node";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], // track requests by IP address rules: [ tokenBucket({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only refillRate: 10, // refill 10 tokens per interval interval: 60, // 60 second interval capacity: 100, // bucket maximum capacity of 100 tokens }), ],});import arcjet, { tokenBucket } from "@arcjet/sveltekit";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], // track requests by IP address rules: [ tokenBucket({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only refillRate: 10, // refill 10 tokens per interval interval: 60, // 60 second interval capacity: 100, // bucket maximum capacity of 100 tokens }), ],});Identifying users
Rate limit rules use characteristics to identify the client and apply the
limit across requests. The default is to use the client’s IP address. However,
you can specify other
characteristics such as a user
ID or other metadata from your application.
In this example we define a rate limit rule that applies to a specific user ID.
The custom characteristic is userId with the value passed as a prop on the
protect function. You can use any string for the characteristic name and any
string, number or boolean for the value.
import arcjet, { fixedWindow } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com // Define a custom userId characteristic. // See https://docs.arcjet.com/rate-limiting/configuration#characteristics characteristics: ["userId"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { // Pass userId as a string to identify the user. This could also be a number // or boolean value const decision = await aj.protect(req, { userId: "user123" }); console.log("Arcjet decision", decision);
if (decision.isDenied()) { return new Response("Too many requests", { status: 429 }); } return new Response("Hello world"); }),};import arcjet, { fixedWindow } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY, // Get your site key from https://app.arcjet.com // Define a custom userId characteristic. // See https://docs.arcjet.com/rate-limiting/configuration#characteristics characteristics: ["userId"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { // Pass userId as a string to identify the user. This could also be a number // or boolean value const decision = await aj.protect(req, { userId: "user123" }); console.log("Arcjet decision", decision);
if (decision.isDenied()) { return new Response("Too many requests", { status: 429 }); } return new Response("Hello world"); }),};import { env } from "$env/dynamic/private";import arcjet, { fixedWindow } from "@arcjet/sveltekit";import { error, json, type RequestEvent } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY!, // Define a custom userId characteristic. // See https://docs.arcjet.com/architecture#custom-characteristics characteristics: ["userId"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(event: RequestEvent) { // Pass userId as a string to identify the user. This could also be a number // or boolean value. const decision = await aj.protect(event, { userId: "user123" });
if (decision.isDenied()) { return error(429, { message: "Too many requests" }); }
return json({ message: "Hello world" });}import { env } from "$env/dynamic/private";import arcjet, { fixedWindow } from "@arcjet/sveltekit";import { error, json } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY, // Define a custom userId characteristic. // See https://docs.arcjet.com/architecture#custom-characteristics characteristics: ["userId"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(event) { // Pass userId as a string to identify the user. This could also be a number // or boolean value. const decision = await aj.protect(event, { userId: "user123" });
if (decision.isDenied()) { return error(429, { message: "Too many requests" }); }
return json({ message: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Define a custom userId characteristic. // See https://docs.arcjet.com/architecture#custom-characteristics characteristics: ["userId"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default async function handler(req, res) { // Pass userId as a string to identify the user. This could also be a number // or boolean value. const decision = await aj.protect(req, { userId: "user123" });
if (decision.isDenied()) { return res.status(429).json({ error: "Too Many Requests" }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";import type { NextApiRequest, NextApiResponse } from "next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Define a custom userId characteristic. // See https://docs.arcjet.com/architecture#custom-characteristics characteristics: ["userId"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default async function handler( req: NextApiRequest, res: NextApiResponse,) { // Pass userId as a string to identify the user. This could also be a number // or boolean value. const decision = await aj.protect(req, { userId: "user123" });
if (decision.isDenied()) { return res.status(429).json({ error: "Too Many Requests" }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Define a custom userId characteristic. // See https://docs.arcjet.com/architecture#custom-characteristics characteristics: ["userId"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(req: Request) { // Pass userId as a string to identify the user. This could also be a number // or boolean value. const decision = await aj.protect(req, { userId: "user123" });
if (decision.isDenied()) { return NextResponse.json( { error: "Too Many Requests", reason: decision.reason, }, { status: 429, }, ); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { fixedWindow } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Define a custom userId characteristic. // See https://docs.arcjet.com/architecture#custom-characteristics characteristics: ["userId"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(req) { // Pass userId as a string to identify the user. This could also be a number // or boolean value. const decision = await aj.protect(req, { userId: "user123" });
if (decision.isDenied()) { return NextResponse.json( { error: "Too Many Requests", reason: decision.reason, }, { status: 429, }, ); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { fixedWindow } from "@arcjet/node";import http from "node:http";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Get your site key from https://app.arcjet.com // Define a custom userId characteristic. // See https://docs.arcjet.com/rate-limiting/configuration#characteristics characteristics: ["userId"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
const server = http.createServer(async function (req, res) { // Pass userId as a string to identify the user. This could also be a number // or boolean value const decision = await aj.protect(req, { userId: "user123" }); console.log("Arcjet decision", decision);
if (decision.isDenied()) { res.writeHead(429, { "Content-Type": "application/json" }); res.end( JSON.stringify({ error: "Too Many Requests", reason: decision.reason }), ); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello world" })); }});
server.listen(8000);import arcjet, { fixedWindow } from "@arcjet/node";import http from "node:http";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com // Define a custom userId characteristic. // See https://docs.arcjet.com/rate-limiting/configuration#characteristics characteristics: ["userId"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
const server = http.createServer(async function ( req: http.IncomingMessage, res: http.ServerResponse,) { // Pass userId as a string to identify the user. This could also be a number // or boolean value const decision = await aj.protect(req, { userId: "user123" }); console.log("Arcjet decision", decision);
if (decision.isDenied()) { res.writeHead(429, { "Content-Type": "application/json" }); res.end( JSON.stringify({ error: "Too Many Requests", reason: decision.reason }), ); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello world" })); }});
server.listen(8000);To identify users with different characteristics e.g. IP address for anonymous users and a user ID for logged in users, you can create a custom fingerprint. See the example in the custom characteristics section.
Rules
The arcjet client is configured with one or more rules which take one or many
of the above options.
Example - single rate limit
Set a single rate limit rule on the /api/hello API route that applies a 60
request limit per hour per IP address (the default if no characteristics are
specified).
import arcjet, { fixedWindow } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});import arcjet, { slidingWindow } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], // track requests by IP address rules: [ slidingWindow({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only interval: 60, // 60 second sliding window max: 100, // allow a maximum of 100 requests }), ],});import arcjet, { fixedWindow } from "@arcjet/node";
const aj = arcjet({ key: process.env.ARCJET_KEY!, rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});import { env } from "$env/dynamic/private";import arcjet, { fixedWindow } from "@arcjet/sveltekit";
const aj = arcjet({ key: env.ARCJET_KEY!, rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});Example - dry run mode for new rules
Rate limits can be combined in the arcjet client which allows you to test new
configurations in dry run mode first before enabling them in live mode. You can
inspect the results of each rule by logging them or using the Arcjet
Dashboard.
import arcjet, { fixedWindow } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], rules: [ // This rule is live fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), // This rule is in dry run mode, so will log but not block fixedWindow({ mode: "DRY_RUN", characteristics: ['http.request.headers["x-api-key"]'], window: "1h", // max could also be a dynamic value applied after looking up a limit // elsewhere e.g. in a database for the authenticated user max: 600, }), ],});import arcjet, { fixedWindow } from "@arcjet/node";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], rules: [ // This rule is live fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), // This rule is in dry run mode, so will log but not block fixedWindow({ mode: "DRY_RUN", characteristics: ['http.request.headers["x-api-key"]'], window: "1h", // max could also be a dynamic value applied after looking up a limit // elsewhere e.g. in a database for the authenticated user max: 600, }), ],});import arcjet, { fixedWindow } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], rules: [ // This rule is live fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), // This rule is in dry run mode, so will log but not block fixedWindow({ mode: "DRY_RUN", // Setting the characteristics in the rule itself overrides the global // setting characteristics: ['http.request.headers["x-api-key"]'], window: "1h", // max could also be a dynamic value applied after looking up a limit // elsewhere e.g. in a database for the authenticated user max: 600, }), ],});import { env } from "$env/dynamic/private";import arcjet, { fixedWindow } from "@arcjet/sveltekit";
const aj = arcjet({ key: env.ARCJET_KEY!, characteristics: ["ip.src"], rules: [ // This rule is live fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), // This rule is in dry run mode, so will log but not block fixedWindow({ mode: "DRY_RUN", characteristics: ['http.request.headers["x-api-key"]'], window: "1h", // max could also be a dynamic value applied after looking up a limit // elsewhere e.g. in a database for the authenticated user max: 600, }), ],});Per route vs middleware
Rate limit rules can be configured in two ways:
- Per API route: The rule is defined in the API route itself. This allows you to configure the rule alongside the code it is protecting which is useful if you want to use the decision to add context to your own code. However, it means rules are not located in a single place.
- Middleware: The rule is defined in the middleware. This allows you to configure rules in a single place or apply them globally to all routes, but it means the rules are not located alongside the code they are protecting.
Per route
If you define your rate limit within an API route Arcjet assumes that the limit
applies only to that route. If you define your rate limit in middleware, you
should either use the Next.js matcher config to choose which paths to execute
the middleware for, or use request.nextUrl.pathname.startsWith.
Rate limit only on /api/*
You can use conditionals in your Next.js middleware to match multiple paths.
import type { NextFetchEvent, NextRequest } from "next/server";import arcjet, { createMiddleware, fixedWindow } from "@arcjet/next";export const config = { // matcher tells Next.js which routes to run the middleware on. // This runs the middleware on all routes except for static assets. matcher: ["/((?!_next/static|_next/image|favicon.ico).*)"],};const aj = arcjet({ key: process.env.ARCJET_KEY!, rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
// Pass any existing middleware with the optional existingMiddleware propconst ajMiddleware = createMiddleware(aj);
export default function middleware( request: NextRequest, event: NextFetchEvent,) { // Only run the Arcjet middleware on API routes if (request.nextUrl.pathname.startsWith("/api")) { return ajMiddleware(request, event); }}Rate limit on all routes
import arcjet, { createMiddleware, fixedWindow } from "@arcjet/next";export const config = { // matcher tells Next.js which routes to run the middleware on. // This runs the middleware on all routes except for static assets. matcher: ["/((?!_next/static|_next/image|favicon.ico).*)"],};const aj = arcjet({ key: process.env.ARCJET_KEY!, rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});// Pass any existing middleware with the optional existingMiddleware propexport default createMiddleware(aj);Avoiding double protection with middleware
If you use Arcjet in middleware and individual routes, you need to be careful that Arcjet is not running multiple times per request. This can be avoided by excluding the API route from the middleware matcher.
For example, if you already have a rate limit defined in the API route at
/api/hello, you can exclude it from the middleware by specifying a matcher in
/middleware.ts:
import arcjet, { createMiddleware, fixedWindow } from "@arcjet/next";export const config = { // The matcher prevents the middleware executing on the /api/hello API route // because you already installed Arcjet directly in the route matcher: ["/((?!_next/static|_next/image|favicon.ico|api/hello).*)"],};const aj = arcjet({ key: process.env.ARCJET_KEY!, rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});export default createMiddleware(aj);Per route vs hooks
Rate limit rules can be configured in two ways:
- Per route: The rule is defined in the route handler itself. This allows you to configure the rule alongside the code it is protecting which is useful if you want to use the decision to add context to your own code. However, it means rules are not located in a single place.
- Hooks: The rule is defined as a hook. This allows you to configure rules in a single place or apply them globally to all routes, but it means the rules are not located alongside the code they are protecting.
Per route
If you define your rate limit within an API route Arcjet assumes that the limit
applies only to that route. If you define your rate limit in hooks, you should
use event.url.pathname.startsWith.
Rate limit only on /api/*
import { env } from "$env/dynamic/private";import arcjet, { fixedWindow } from "@arcjet/sveltekit";import { error, type RequestEvent } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY!, rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function handle({ event, resolve,}: { event: RequestEvent; resolve: (event: RequestEvent) => Response | Promise<Response>;}): Promise<Response> { // Only run the Arcjet hook on API routes if (event.url.pathname.startsWith("/api/")) { const decision = await aj.protect(event); if (decision.isDenied()) { return error(429, "Too many requests"); } }
return resolve(event);}Rate limit on all routes
import { env } from "$env/dynamic/private";import arcjet, { fixedWindow } from "@arcjet/sveltekit";import { error, type RequestEvent } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY!, rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function handle({ event, resolve,}: { event: RequestEvent; resolve: (event: RequestEvent) => Response | Promise<Response>;}): Promise<Response> { const decision = await aj.protect(event);
if (decision.isDenied()) { return error(429, "Too many requests"); }
return resolve(event);}Avoiding double protection with hooks
If you use Arcjet in hooks and individual routes, you need to be careful that Arcjet is not running multiple times per request. This can be avoided by excluding the individual routes before running Arcjet in the hook.
For example, if you already have a rule defined in the route at /api, you can
exclude it from the hook like this:
import { env } from "$env/dynamic/private";import arcjet, { fixedWindow } from "@arcjet/sveltekit";import { error, type RequestEvent } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY!, rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function handle({ event, resolve,}: { event: RequestEvent; resolve: (event: RequestEvent) => Response | Promise<Response>;}): Promise<Response> { // Ignore routes that extend the Arcjet rules // - they will call `.protect` themselves const filteredRoutes = ["/api/"]; if (filteredRoutes.includes(event.url.pathname)) { // return - route will handle protecttion return resolve(event); }
const decision = await aj.protect(event);
if (decision.isDenied()) { return error(429, "Too many requests"); }
return resolve(event);}Decision
Arcjet provides a single protect function that is used to execute your
protection rules. This requires a RequestEvent property which is the event
context as passed to the request handler.
This function returns a Promise that resolves to an
ArcjetDecision object. This contains the following properties:
id(string) - The unique ID for the request. This can be used to look up the request in the Arcjet dashboard. It is prefixed withreq_for decisions involving the Arcjet cloud API. For decisions taken locally, the prefix islreq_.conclusion(ArcjetConclusion) - The final conclusion based on evaluating each of the configured rules. If you wish to accept Arcjet’s recommended action based on the configured rules then you can use this property.reason(ArcjetReason) - An object containing more detailed information about the conclusion.results(ArcjetRuleResult[]) - An array ofArcjetRuleResultobjects containing the results of each rule that was executed.ip(ArcjetIpDetails) - An object containing Arcjet’s analysis of the client IP address. See the SDK reference for more information.
You check if a deny conclusion has been returned by a rate limit rule by using
decision.isDenied() and decision.reason.isRateLimit().
You can iterate through the results and check whether a rate limit was applied:
for (const result of decision.results) { console.log("Rule Result", result);}This example will log the full result as well as each rate limit rule:
import arcjet, { detectBot, fixedWindow } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { const decision = await aj.protect(req);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isRateLimit()) { console.log("Rate limit rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { if (decision.reason.isRateLimit()) { return new Response("Too many requests", { status: 429 }); } else { return new Response("Forbidden", { status: 403 }); } }
return new Response("Hello world"); }),};import arcjet, { detectBot, fixedWindow } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { const decision = await aj.protect(req);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isRateLimit()) { console.log("Rate limit rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { if (decision.reason.isRateLimit()) { return new Response("Too many requests", { status: 429 }); } else { return new Response("Forbidden", { status: 403 }); } }
return new Response("Hello world"); }),};import arcjet, { fixedWindow, detectBot } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export async function POST(req: Request) { const decision = await aj.protect(req);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isRateLimit()) { console.log("Rate limit rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { return NextResponse.json({ error: "Forbidden" }, { status: 403 }); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { fixedWindow, detectBot } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export async function POST(req) { const decision = await aj.protect(req);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isRateLimit()) { console.log("Rate limit rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { return NextResponse.json({ error: "Forbidden" }, { status: 403 }); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { fixedWindow, detectBot } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export default async function handler(req, res) { const decision = await aj.protect(req); console.log("Decision", decision);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isRateLimit()) { console.log("Rate limit rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { return res .status(403) .json({ error: "Forbidden", reason: decision.reason }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow, detectBot } from "@arcjet/next";import type { NextApiRequest, NextApiResponse } from "next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export default async function handler( req: NextApiRequest, res: NextApiResponse,) { const decision = await aj.protect(req); console.log("Decision", decision);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isRateLimit()) { console.log("Rate limit rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { return res .status(403) .json({ error: "Forbidden", reason: decision.reason }); }
res.status(200).json({ name: "Hello world" });}import { env } from "$env/dynamic/private";import arcjet, { detectBot, fixedWindow } from "@arcjet/sveltekit";import { error, json, type RequestEvent } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export async function GET(event: RequestEvent) { const decision = await aj.protect(event);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isRateLimit()) { console.log("Rate limit rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { return error(403, "Forbidden"); }
return json({ message: "Hello world" });}import { env } from "$env/dynamic/private";import arcjet, { detectBot, fixedWindow } from "@arcjet/sveltekit";import { error, json } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
export async function GET(event) { const decision = await aj.protect(event);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isRateLimit()) { console.log("Rate limit rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { return error(403, "Forbidden"); }
return json({ message: "Hello world" });}import arcjet, { fixedWindow, detectBot } from "@arcjet/node";import http from "node:http";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
const server = http.createServer(async function (req, res) { const decision = await aj.protect(req);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isRateLimit()) { console.log("Rate limit rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { if (decision.reason.isRateLimit()) { res.writeHead(429, { "Content-Type": "application/json" }); res.end( JSON.stringify({ error: "Too Many Requests", reason: decision.reason }), ); res.end(JSON.stringify({ error: "Forbidden" })); } else { res.writeHead(403, { "Content-Type": "application/json" }); res.end(JSON.stringify({ error: "Forbidden" })); } } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello world" })); }});
server.listen(8000);import arcjet, { fixedWindow, detectBot } from "@arcjet/node";import http from "node:http";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), detectBot({ mode: "LIVE", allow: [], // "allow none" will block all detected bots }), ],});
const server = http.createServer(async function ( req: http.IncomingMessage, res: http.ServerResponse,) { const decision = await aj.protect(req);
for (const result of decision.results) { console.log("Rule Result", result);
if (result.reason.isRateLimit()) { console.log("Rate limit rule", result); }
if (result.reason.isBot()) { console.log("Bot protection rule", result); } }
if (decision.isDenied()) { if (decision.reason.isRateLimit()) { res.writeHead(429, { "Content-Type": "application/json" }); res.end( JSON.stringify({ error: "Too Many Requests", reason: decision.reason }), ); res.end(JSON.stringify({ error: "Forbidden" })); } else { res.writeHead(403, { "Content-Type": "application/json" }); res.end(JSON.stringify({ error: "Forbidden" })); } } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello world" })); }});
server.listen(8000);Token bucket request
When using a token bucket rule, an additional requested prop should be passed
to the protect function. This is the number of tokens the client is requesting
to withdraw from the bucket.
import arcjet, { tokenBucket } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], rules: [ tokenBucket({ mode: "LIVE", refillRate: 40_000, interval: "1d", capacity: 40_000, }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { const decision = await aj.protect(req, { requested: 50 }); console.log("Arcjet decision", decision);
if (decision.isDenied()) { return new Response("Too many requests", { status: 429 }); }
return new Response("Hello world"); }),};import arcjet, { tokenBucket } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], rules: [ tokenBucket({ mode: "LIVE", refillRate: 40_000, interval: "1d", capacity: 40_000, }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { const decision = await aj.protect(req, { requested: 50 }); console.log("Arcjet decision", decision);
if (decision.isDenied()) { return new Response("Too many requests", { status: 429 }); }
return new Response("Hello world"); }),};import { env } from "$env/dynamic/private";import arcjet, { tokenBucket } from "@arcjet/sveltekit";import { error, json, type RequestEvent } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY!, characteristics: ["ip.src"], rules: [ tokenBucket({ mode: "LIVE", refillRate: 40_000, interval: "1d", capacity: 40_000, }), ],});
export async function GET(event: RequestEvent) { const decision = await aj.protect(event, { requested: 50 });
if (decision.isDenied()) { return error(429, { message: "Too many requests" }); }
return json({ message: "Hello world" });}import { env } from "$env/dynamic/private";import arcjet, { tokenBucket } from "@arcjet/sveltekit";import { error, json } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY, characteristics: ["ip.src"], rules: [ tokenBucket({ mode: "LIVE", refillRate: 40_000, interval: "1d", capacity: 40_000, }), ],});
export async function GET(event) { const decision = await aj.protect(event, { requested: 50 });
if (decision.isDenied()) { return error(429, { message: "Too many requests" }); }
return json({ message: "Hello world" });}import arcjet, { tokenBucket } from "@arcjet/next";import type { NextApiRequest, NextApiResponse } from "next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], rules: [ tokenBucket({ mode: "LIVE", refillRate: 40_000, interval: "1d", capacity: 40_000, }), ],});
export default async function handler( req: NextApiRequest, res: NextApiResponse,) { // Each request will consume 50 tokens const decision = await aj.protect(req, { requested: 50 });
if (decision.isDenied()) { return res.status(429).json({ error: "Too Many Requests" }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { tokenBucket } from "@arcjet/next";import type { NextApiRequest, NextApiResponse } from "next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ["ip.src"], rules: [ tokenBucket({ mode: "LIVE", refillRate: 40_000, interval: "1d", capacity: 40_000, }), ],});
export default async function handler( req: NextApiRequest, res: NextApiResponse,) { // Each request will consume 50 tokens const decision = await aj.protect(req, { requested: 50 });
if (decision.isDenied()) { return res.status(429).json({ error: "Too Many Requests" }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { tokenBucket } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, characteristics: ["ip.src"], rules: [ tokenBucket({ mode: "LIVE", refillRate: 40_000, interval: "1d", capacity: 40_000, }), ],});
export async function GET(req) { // Each request will consume 50 tokens const decision = await aj.protect(req, { requested: 50 });
if (decision.isDenied()) { return NextResponse.json( { error: "Too Many Requests", reason: decision.reason, }, { status: 429, }, ); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { tokenBucket } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, characteristics: ["ip.src"], rules: [ tokenBucket({ mode: "LIVE", refillRate: 40_000, interval: "1d", capacity: 40_000, }), ],});
export async function GET(req) { // Each request will consume 50 tokens const decision = await aj.protect(req, { requested: 50 });
if (decision.isDenied()) { return NextResponse.json( { error: "Too Many Requests", reason: decision.reason, }, { status: 429, }, ); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { tokenBucket } from "@arcjet/node";import http from "node:http";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], rules: [ tokenBucket({ mode: "LIVE", refillRate: 40_000, interval: "1d", capacity: 40_000, }), ],});
const server = http.createServer(async function (req, res) { const decision = await aj.protect(req, { requested: 50 }); console.log("Arcjet decision", decision);
if (decision.isDenied()) { res.writeHead(429, { "Content-Type": "application/json" }); res.end( JSON.stringify({ error: "Too Many Requests", reason: decision.reason }), ); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello world" })); }});
server.listen(8000);import arcjet, { tokenBucket } from "@arcjet/node";import http from "node:http";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com characteristics: ["ip.src"], rules: [ tokenBucket({ mode: "LIVE", refillRate: 40_000, interval: "1d", capacity: 40_000, }), ],});
const server = http.createServer(async function ( req: http.IncomingMessage, res: http.ServerResponse,) { const decision = await aj.protect(req, { requested: 50 }); console.log("Arcjet decision", decision);
if (decision.isDenied()) { res.writeHead(429, { "Content-Type": "application/json" }); res.end( JSON.stringify({ error: "Too Many Requests", reason: decision.reason }), ); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello world" })); }});
server.listen(8000);Rate limit headers
With a rate limit rule enabled, you can access additional metadata in every Arcjet decision result:
max(number): The configured maximum number of requests applied to this request.remaining(number): The number of requests remaining beforemaxis reached within the window.window(number): The total amount of seconds in which requests are counted.reset(number): The remaining amount of seconds in the window.
These can be used to return RateLimit HTTP headers (draft
RFC) to
offer the client more detail.
We provide the @arcjet/decorate
package for decorating
your responses with appropriate RateLimit headers based on a decision.
import { env } from "$env/dynamic/private";import { setRateLimitHeaders } from "@arcjet/decorate";import arcjet, { fixedWindow } from "@arcjet/sveltekit";import { error, json, type RequestEvent } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(event: RequestEvent) { const decision = await aj.protect(event);
if (decision.isDenied()) { return error(429, { message: "Too many requests" }); }
const headers = new Headers(); setRateLimitHeaders(headers, decision); return json({ message: "Hello world" }, { headers });}import { env } from "$env/dynamic/private";import { setRateLimitHeaders } from "@arcjet/decorate";import arcjet, { fixedWindow } from "@arcjet/sveltekit";import { error, json } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(event) { const decision = await aj.protect(event);
if (decision.isDenied()) { return error(429, { message: "Too many requests" }); }
const headers = new Headers(); setRateLimitHeaders(headers, decision); return json({ message: "Hello world" }, { headers });}import arcjet, { fixedWindow } from "@arcjet/bun";import { setRateLimitHeaders } from "@arcjet/decorate";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY, // Get your site key from https://app.arcjet.com // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
const ResponseWithRateLimit = (body, init, decision) => { const res = new Response(body, init); setRateLimitHeaders(res, decision); return res;};
export default { port: 3000, fetch: aj.handler(async (req) => { const decision = await aj.protect(req); console.log("Arcjet decision", decision);
if (decision.isDenied()) { return ResponseWithRateLimit( "Too many requests", { status: 429 }, decision, ); }
return ResponseWithRateLimit("Hello world", { status: 200 }, decision); }),};import arcjet, { fixedWindow, type ArcjetDecision } from "@arcjet/bun";import { setRateLimitHeaders } from "@arcjet/decorate";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
const ResponseWithRateLimit = ( body: string, init: ResponseInit, decision: ArcjetDecision,) => { const res = new Response(body, init); setRateLimitHeaders(res, decision); return res;};
export default { port: 3000, fetch: aj.handler(async (req) => { const decision = await aj.protect(req); console.log("Arcjet decision", decision);
if (decision.isDenied()) { return ResponseWithRateLimit( "Too many requests", { status: 429 }, decision, ); }
return ResponseWithRateLimit("Hello world", { status: 200 }, decision); }),};import arcjet, { fixedWindow } from "@arcjet/node";import { setRateLimitHeaders } from "@arcjet/decorate";import http from "node:http";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Get your site key from https://app.arcjet.com // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
const server = http.createServer(async function (req, res) { const decision = await aj.protect(req); console.log("Arcjet decision", decision);
setRateLimitHeaders(res, decision);
if (decision.isDenied()) { res.writeHead(429, { "Content-Type": "application/json" }); res.end( JSON.stringify({ error: "Too Many Requests", reason: decision.reason }), ); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello world" })); }});
server.listen(8000);import arcjet, { fixedWindow } from "@arcjet/node";import { setRateLimitHeaders } from "@arcjet/decorate";import http from "node:http";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
const server = http.createServer(async function ( req: http.IncomingMessage, res: http.ServerResponse,) { const decision = await aj.protect(req); console.log("Arcjet decision", decision);
setRateLimitHeaders(res, decision);
if (decision.isDenied()) { res.writeHead(429, { "Content-Type": "application/json" }); res.end( JSON.stringify({ error: "Too Many Requests", reason: decision.reason }), ); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello world" })); }});
server.listen(8000);import arcjet, { fixedWindow } from "@arcjet/next";import { setRateLimitHeaders } from "@arcjet/decorate";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default async function handler(req, res) { const decision = await aj.protect(req);
setRateLimitHeaders(res, decision);
if (decision.isDenied()) { return res.status(429).json({ error: "Too Many Requests" }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";import { setRateLimitHeaders } from "@arcjet/decorate";import type { NextApiRequest, NextApiResponse } from "next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default async function handler( req: NextApiRequest, res: NextApiResponse,) { const decision = await aj.protect(req);
setRateLimitHeaders(res, decision);
if (decision.isDenied()) { return res.status(429).json({ error: "Too Many Requests" }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";import { setRateLimitHeaders } from "@arcjet/decorate";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(req: Request) { const decision = await aj.protect(req);
const headers = new Headers();
setRateLimitHeaders(headers, decision);
if (decision.isDenied()) { return NextResponse.json( { error: "Too Many Requests", reason: decision.reason, }, { status: 429, headers }, ); }
return NextResponse.json( { message: "Hello world", }, { status: 200, headers }, );}import arcjet, { fixedWindow } from "@arcjet/next";import { setRateLimitHeaders } from "@arcjet/decorate";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(req) { const decision = await aj.protect(req);
const headers = new Headers();
setRateLimitHeaders(headers, decision);
if (decision.isDenied()) { return NextResponse.json( { error: "Too Many Requests", reason: decision.reason, }, { status: 429, headers }, ); }
return NextResponse.json( { message: "Hello world", }, { status: 200, headers }, );}Error handling
Arcjet is designed to fail open so that a service issue or misconfiguration does
not block all requests. The SDK will also time out and fail open after 1000ms
when NODE_ENV or ARCJET_ENV is development and 500ms otherwise. However,
in most cases, the response time will be less than 20-30ms.
If there is an error condition, Arcjet will return an ERROR conclusion.
import arcjet, { tokenBucket } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com characteristics: ["userId"], // track requests by a custom user ID rules: [ // Create a token bucket rate limit. Other algorithms are supported. tokenBucket({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only refillRate: 5, // refill 5 tokens per interval interval: 10, // refill every 10 seconds capacity: 10, // bucket maximum capacity of 10 tokens }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { const userId = "user123"; // Replace with your authenticated user ID const decision = await aj.protect(req, { userId, requested: 5 }); // Deduct 5 tokens from the bucket console.log("Arcjet decision", decision);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return new Response("Service unavailable", { status: 503 }); }
if (decision.isDenied()) { return new Response("Too many requests", { status: 429 }); }
return new Response("Hello world"); }),};import arcjet, { tokenBucket } from "@arcjet/bun";import { env } from "bun";
const aj = arcjet({ key: env.ARCJET_KEY, // Get your site key from https://app.arcjet.com characteristics: ["userId"], // track requests by a custom user ID rules: [ // Create a token bucket rate limit. Other algorithms are supported. tokenBucket({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only refillRate: 5, // refill 5 tokens per interval interval: 10, // refill every 10 seconds capacity: 10, // bucket maximum capacity of 10 tokens }), ],});
export default { port: 3000, fetch: aj.handler(async (req) => { const userId = "user123"; // Replace with your authenticated user ID const decision = await aj.protect(req, { userId, requested: 5 }); // Deduct 5 tokens from the bucket console.log("Arcjet decision", decision);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return new Response("Service unavailable", { status: 503 }); }
if (decision.isDenied()) { return new Response("Too many requests", { status: 429 }); }
return new Response("Hello world"); }),};import { env } from "$env/dynamic/private";import arcjet, { fixedWindow } from "@arcjet/sveltekit";import { error, json, type RequestEvent } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(event: RequestEvent) { const decision = await aj.protect(event);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return error(503, { message: "Service unavailable" }); }
if (decision.isDenied()) { return error(429, { message: "Too many requests" }); }
return json({ message: "Hello world" });}import { env } from "$env/dynamic/private";import arcjet, { fixedWindow } from "@arcjet/sveltekit";import { error, json } from "@sveltejs/kit";
const aj = arcjet({ key: env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(event) { const decision = await aj.protect(event);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return error(503, { message: "Service unavailable" }); }
if (decision.isDenied()) { return error(429, { message: "Too many requests" }); }
return json({ message: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default async function handler(req, res) { const decision = await aj.protect(req);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return res.status(503).json({ error: "Service unavailable" }); }
if (decision.isDenied()) { return res.status(429).json({ error: "Too Many Requests" }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";import type { NextApiRequest, NextApiResponse } from "next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default async function handler( req: NextApiRequest, res: NextApiResponse,) { const decision = await aj.protect(req);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return res.status(503).json({ error: "Service unavailable" }); }
if (decision.isDenied()) { return res.status(429).json({ error: "Too Many Requests" }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(req: Request) { const decision = await aj.protect(req);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return NextResponse.json({ error: "Service unavailable" }, { status: 503 }); }
if (decision.isDenied()) { return NextResponse.json( { error: "Too Many Requests", reason: decision.reason, }, { status: 429, }, ); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { fixedWindow } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(req) { const decision = await aj.protect(req);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //return NextResponse.json({ error: "Service unavailable" }, { status: 503 }); }
if (decision.isDenied()) { return NextResponse.json( { error: "Too Many Requests", reason: decision.reason, }, { status: 429, }, ); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { tokenBucket } from "@arcjet/node";import http from "node:http";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Get your site key from https://app.arcjet.com characteristics: ["userId"], // track requests by a custom user ID rules: [ // Create a token bucket rate limit. Other algorithms are supported. tokenBucket({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only refillRate: 5, // refill 5 tokens per interval interval: 10, // refill every 10 seconds capacity: 10, // bucket maximum capacity of 10 tokens }), ],});
const server = http.createServer(async function (req, res) { const userId = "user123"; // Replace with your authenticated user ID const decision = await aj.protect(req, { userId, requested: 5 }); // Deduct 5 tokens from the bucket console.log("Arcjet decision", decision);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //res.writeHead(503, { "Content-Type": "application/json" }); //res.end(JSON.stringify({ error: "Service unavailable" })); }
if (decision.isDenied()) { res.writeHead(429, { "Content-Type": "application/json" }); res.end( JSON.stringify({ error: "Too Many Requests", reason: decision.reason }), ); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello world" })); }});
server.listen(8000);import arcjet, { tokenBucket } from "@arcjet/node";import http from "node:http";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Get your site key from https://app.arcjet.com characteristics: ["userId"], // track requests by a custom user ID rules: [ // Create a token bucket rate limit. Other algorithms are supported. tokenBucket({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only refillRate: 5, // refill 5 tokens per interval interval: 10, // refill every 10 seconds capacity: 10, // bucket maximum capacity of 10 tokens }), ],});
const server = http.createServer(async function ( req: http.IncomingMessage, res: http.ServerResponse,) { const userId = "user123"; // Replace with your authenticated user ID const decision = await aj.protect(req, { userId, requested: 5 }); // Deduct 5 tokens from the bucket console.log("Arcjet decision", decision);
if (decision.isErrored()) { // Fail open by logging the error and continuing console.warn("Arcjet error", decision.reason.message); // You could also fail closed here for very sensitive routes //res.writeHead(503, { "Content-Type": "application/json" }); //res.end(JSON.stringify({ error: "Service unavailable" })); }
if (decision.isDenied()) { res.writeHead(429, { "Content-Type": "application/json" }); res.end( JSON.stringify({ error: "Too Many Requests", reason: decision.reason }), ); } else { res.writeHead(200, { "Content-Type": "application/json" }); res.end(JSON.stringify({ message: "Hello world" })); }});
server.listen(8000);Testing
Arcjet runs the same in any environment, including locally and in CI. You can
use the mode set to DRY_RUN to log the results of rule execution without
blocking any requests.
We have an example test framework you can use to automatically test your rules. Arcjet can also be triggered based using a sample of your traffic.
See the Testing section of the docs for details.
Examples
Rate limit by IP address
The example below shows how to configure a rate limit on a single API route. It applies a limit of 60 requests per hour per IP address. If the limit is exceeded, the client is blocked for 10 minutes before being able to make any further requests.
Applying a rate limit by IP address is the default if no
characteristics are specified.
import arcjet, { fixedWindow } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified // characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default async function handler(req, res) { const decision = await aj.protect(req);
if (decision.isDenied()) { return res.status(429).json({ error: "Too Many Requests" }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";import type { NextApiRequest, NextApiResponse } from "next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified // characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default async function handler( req: NextApiRequest, res: NextApiResponse,) { const decision = await aj.protect(req);
if (decision.isDenied()) { return res.status(429).json({ error: "Too Many Requests" }); }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified // characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(req: Request) { const decision = await aj.protect(req);
if (decision.isDenied()) { return NextResponse.json( { error: "Too Many Requests", reason: decision.reason, }, { status: 429, }, ); }
return NextResponse.json({ message: "Hello world", });}import arcjet, { fixedWindow } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified // characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(req) { const decision = await aj.protect(req);
if (decision.isDenied()) { return NextResponse.json( { error: "Too Many Requests", reason: decision.reason, }, { status: 429, }, ); }
return NextResponse.json({ message: "Hello world", });}Rate limit by IP address with custom response
The example below is the same as the one above. However this example also shows a customized response rather than the default.
import arcjet, { fixedWindow } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified // characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default async function handler(req, res) { const decision = await aj.protect(req);
if (decision.isDenied()) { if (decision.reason.isRateLimit()) { return res.status(429).json({ error: "Too Many Requests" }); } else { return res .status(403) .json({ error: "Forbidden", reason: decision.reason }); } }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified // characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(req: Request) { const decision = await aj.protect(req);
if (decision.isDenied()) { if (decision.reason.isRateLimit()) { return NextResponse.json({ error: "Too Many Requests" }, { status: 429 }); } else { return NextResponse.json( { error: "Forbidden", reason: decision.reason }, { status: 403 }, ); } }
return NextResponse.json({ message: "Hello world", });}import arcjet, { fixedWindow } from "@arcjet/next";import type { NextApiRequest, NextApiResponse } from "next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified // characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default async function handler( req: NextApiRequest, res: NextApiResponse,) { const decision = await aj.protect(req);
if (decision.isDenied()) { if (decision.reason.isRateLimit()) { return res.status(429).json({ error: "Too Many Requests" }); } else { return res .status(403) .json({ error: "Forbidden", reason: decision.reason }); } }
res.status(200).json({ name: "Hello world" });}import arcjet, { fixedWindow } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified // characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function GET(req) { const decision = await aj.protect(req);
if (decision.isDenied()) { if (decision.reason.isRateLimit()) { return res.status(429).json({ error: "Too Many Requests" }); } else { return res .status(403) .json({ error: "Forbidden", reason: decision.reason }); } }
return NextResponse.json({ message: "Hello world", });}Rate limit by AI tokens
If you are building an AI application you may be more interested in the number of AI tokens rather than the number of HTTP requests. Popular AI APIs such as OpenAI are billed based on the number of tokens consumed and the number of tokens is variable depending on the request e.g. conversation length or image size.
The token bucket algorithm is a good fit for this use case because you can vary the number of tokens withdrawn from the bucket with every request.
The example below configures a token bucket rate limit using the
openai-chat-tokens library to
track the number of tokens used by a gpt-3.5-turbo AI chatbot. It sets a limit
of 2,000 tokens per hour with a maximum of 5,000 tokens in the bucket. This
allows for a reasonable conversation length without consuming too many tokens.
See the arcjet-js GitHub repo for a full example using Next.js.
The Next.js pages router does not support streaming responses so you should
use the app router for this example. You can still use the pages/
directory for the rest of your application. See the Next.js AI docs for
details.
The Next.js pages router does not support streaming responses so you should
use the app router for this example. You can still use the pages/
directory for the rest of your application. See the Next.js AI docs for
details.
// This example is adapted from https://sdk.vercel.ai/docs/guides/frameworks/nextjs-appimport arcjet, { tokenBucket } from "@arcjet/next";import { OpenAIStream, StreamingTextResponse } from "ai";import OpenAI from "openai";import { promptTokensEstimate } from "openai-chat-tokens";
const aj = arcjet({ // Get your site key from https://app.arcjet.com // and set it as an environment variable rather than hard coding. // See: https://nextjs.org/docs/app/building-your-application/configuring/environment-variables key: process.env.AJ_KEY!, characteristics: ["ip.src"], // track requests by IP address rules: [ tokenBucket({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only refillRate: 2_000, interval: "1h", capacity: 5_000, }), ],});
// OpenAI clientconst openai = new OpenAI({ apiKey: process.env.OPENAI_API_KEY ?? "OPENAI_KEY_MISSING",});
// Edge runtime allows for streaming responsesexport const runtime = "edge";
export async function POST(req: Request) { const { messages } = await req.json();
// Estimate the number of tokens required to process the request const estimate = promptTokensEstimate({ messages, });
console.log("Token estimate", estimate);
// Withdraw tokens from the token bucket const decision = await aj.protect(req, { requested: estimate }); console.log("Arcjet decision", decision.conclusion);
if (decision.reason.isRateLimit()) { console.log("Requests remaining", decision.reason.remaining); }
// If the request is denied, return a 429 if (decision.isDenied()) { if (decision.reason.isRateLimit()) { return new Response("Too Many Requests", { status: 429, }); } else { return new Response("Forbidden", { status: 403, }); } }
// If the request is allowed, continue to use OpenAI // Ask OpenAI for a streaming chat completion given the prompt const response = await openai.chat.completions.create({ model: "gpt-3.5-turbo", stream: true, messages, });
// Convert the response into a friendly text-stream const stream = OpenAIStream(response); // Respond with the stream return new StreamingTextResponse(stream);}// This example is adapted from https://sdk.vercel.ai/docs/guides/frameworks/nextjs-appimport arcjet, { tokenBucket } from "@arcjet/next";import { OpenAIStream, StreamingTextResponse } from "ai";import OpenAI from "openai";import { promptTokensEstimate } from "openai-chat-tokens";
const aj = arcjet({ // Get your site key from https://app.arcjet.com // and set it as an environment variable rather than hard coding. // See: https://nextjs.org/docs/app/building-your-application/configuring/environment-variables key: process.env.AJ_KEY, characteristics: ["ip.src"], // track requests by IP address rules: [ tokenBucket({ mode: "LIVE", // will block requests. Use "DRY_RUN" to log only refillRate: 2_000, interval: "1h", capacity: 5_000, }), ],});
// OpenAI clientconst openai = new OpenAI({ apiKey: process.env.OPENAI_API_KEY ?? "OPENAI_KEY_MISSING",});
// Edge runtime allows for streaming responsesexport const runtime = "edge";
export async function POST(req) { const { messages } = await req.json();
// Estimate the number of tokens required to process the request const estimate = promptTokensEstimate({ messages, });
console.log("Token estimate", estimate);
// Withdraw tokens from the token bucket const decision = await aj.protect(req, { requested: estimate }); console.log("Arcjet decision", decision.conclusion);
if (decision.reason.isRateLimit()) { console.log("Requests remaining", decision.reason.remaining); }
// If the request is denied, return a 429 if (decision.isDenied()) { if (decision.reason.isRateLimit()) { return new Response("Too Many Requests", { status: 429, }); } else { return new Response("Forbidden", { status: 403, }); } }
// If the request is allowed, continue to use OpenAI // Ask OpenAI for a streaming chat completion given the prompt const response = await openai.chat.completions.create({ model: "gpt-3.5-turbo", stream: true, messages, });
// Convert the response into a friendly text-stream const stream = OpenAIStream(response); // Respond with the stream return new StreamingTextResponse(stream);}Rate limit by API key header
APIs are commonly protected by keys. You may wish to apply a rate limit based on the key, regardless of which IPs the requests come from. To achieve this, you can specify the characteristics Arcjet will use to track the limit.
The example below shows how to configure a rate limit on a single API route. It
applies a limit of 60 requests per hour per API key, where the key is provided
in a custom header called x-api-key. If the limit is exceeded, the client is
blocked for 10 minutes before being able to make any further requests.
import arcjet, { fixedWindow } from "@arcjet/next";
const aj = arcjet({ key: process.env.ARCJET_KEY!, characteristics: ['http.request.headers["x-api-key"]'], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});Global rate limit
Using Next.js middleware allows you to set a rate limit that applies to every route:
import arcjet, { createMiddleware, fixedWindow } from "@arcjet/next";export const config = { // matcher tells Next.js which routes to run the middleware on. // This runs the middleware on all routes except for static assets. matcher: ["/((?!_next/static|_next/image|favicon.ico).*)"],};const aj = arcjet({ key: process.env.ARCJET_KEY!, rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});// Pass any existing middleware with the optional existingMiddleware propexport default createMiddleware(aj);Response based on the path
You can also use the req
NextRequest
object to customize the response based on the path. In this example, we’ll
return a JSON response for API requests, and a HTML response for other requests.
import arcjet, { fixedWindow } from "@arcjet/next";import { NextRequest, NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function middleware(req: NextRequest, res: NextResponse) { const decision = await aj.protect(req);
if (decision.isDenied()) { // If this is an API request, return a JSON response if (req.nextUrl.pathname.startsWith("/api")) { return new NextResponse(JSON.stringify({ error: "Too many requests" }), { status: 429, headers: { "content-type": "application/json" }, }); } else { return new NextResponse("Too many requests", { status: 429, headers: { "content-type": "text/html" }, }); } }}Rewrite or redirect
The
NextResponse
object returned to the client can also be used to rewrite or redirect the
request. For example, you might want to return a JSON response for API route
requests, but redirect all page route requests to an error page.
import arcjet, { fixedWindow } from "@arcjet/next";import { NextRequest, NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export async function middleware(req: NextRequest, res: NextResponse) { const decision = await aj.protect(req);
if (decision.isDenied()) { // If this is an API request, return a JSON response if (req.nextUrl.pathname.startsWith("/api")) { return new NextResponse(JSON.stringify({ error: "Too many requests" }), { status: 429, headers: { "content-type": "application/json" }, }); } else { return NextResponse.redirect("/rate-limited"); } }}Wrap existing handler
All the examples on this page show how you can inspect the decision to control
what to do next. However, if you just wish to send a generic 429 Too Many Requests response you can delegate this to Arcjet by wrapping your handler
withArcjet.
For both the Node or Edge runtime:
import arcjet, { fixedWindow, withArcjet } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export const GET = withArcjet(aj, async (req: Request) => { return NextResponse.json({ message: "Hello world", });});or both the Node or Edge runtime:
import arcjet, { fixedWindow, withArcjet } from "@arcjet/next";import { NextResponse } from "next/server";
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export const GET = withArcjet(aj, async (req) => { return NextResponse.json({ message: "Hello world", });});For the Node (default) runtime:
import arcjet, { fixedWindow, withArcjet } from "@arcjet/next";import type { NextApiRequest, NextApiResponse } from "next";
export const config = { runtime: "edge",};
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default withArcjet( aj, async (req: NextApiRequest, res: NextApiResponse) => { res.status(200).json({ name: "Hello world" }); },);For the Edge runtime:
import arcjet, { fixedWindow, withArcjet } from "@arcjet/next";import { NextRequest, NextResponse } from "next/server";
export const config = { runtime: "edge",};
const aj = arcjet({ key: process.env.ARCJET_KEY!, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default withArcjet(aj, async (req: NextRequest) => { return NextResponse.json({ message: "Hello world", });});For the Node (default) runtime:
import arcjet, { fixedWindow, withArcjet } from "@arcjet/next";
export const config = { runtime: "edge",};
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default withArcjet(aj, async (req, res) => { res.status(200).json({ name: "Hello world" });});For the Edge runtime:
import arcjet, { fixedWindow, withArcjet } from "@arcjet/next";import { NextRequest, NextResponse } from "next/server";
export const config = { runtime: "edge",};
const aj = arcjet({ key: process.env.ARCJET_KEY, // Tracking by ip.src is the default if not specified //characteristics: ["ip.src"], rules: [ fixedWindow({ mode: "LIVE", window: "1h", max: 60, }), ],});
export default withArcjet(aj, async (req) => { return NextResponse.json({ message: "Hello world", });});