Cloudflare Worker JWT

A lightweight JWT implementation with ZERO dependencies for Cloudflare Workers.

Contents

• Install
• Examples
• Usage
  • Sign
  • Verify
  • Decode

Install

npm i @tsndr/cloudflare-worker-jwt

Examples

Basic Example

async () => {
    import jwt from "@tsndr/cloudflare-worker-jwt"

    // Create a token
    const token = await jwt.sign({
        sub: "1234",
        name: "John Doe",
        email: "john.doe@gmail.com"
    }, "secret")

    // Verify token
    const verifiedToken = await jwt.verify(token, "secret")

    // Abort if token isn't valid
    if (!verifiedToken)
        return

    // Access token payload
    const { payload } = verifiedToken

    // { sub: "1234", name: "John Doe", email: "john.doe@gmail.com" }
}

Restrict Timeframe

async () => {
    import jwt from "@tsndr/cloudflare-worker-jwt"

    // Create a token
    const token = await jwt.sign({
        sub: "1234",
        name: "John Doe",
        email: "john.doe@gmail.com",
        nbf: Math.floor(Date.now() / 1000) + (60 * 60),      // Not before: Now + 1h
        exp: Math.floor(Date.now() / 1000) + (2 * (60 * 60)) // Expires: Now + 2h
    }, "secret")

    // Verify token
    const verifiedToken = await jwt.verify(token, "secret")

    // Abort if token isn't valid
    if (!verifiedToken)
        return

    // Access token payload
    const { payload } = verifiedToken

    // { sub: "1234", name: "John Doe", email: "john.doe@gmail.com", ... }
}

Usage

• Sign
• Verify
• Decode

---

Sign

sign(payload, secret, [options])

Signs a payload and returns the token.

Arguments

Argument	Type	Status	Default	Description
payload	object	required	-	The payload object. To use nbf (Not Before) and/or exp (Expiration Time) add nbf and/or exp to the payload.
secret	string, JsonWebKey, CryptoKey	required	-	A string which is used to sign the payload.
options	string, object	optional	HS256	Either the algorithm string or an object.
options.algorithm	string	optional	HS256	See Available Algorithms
options.header	object	optional	undefined	Extend the header of the resulting JWT.

return

Returns token as a string.

---

Verify

verify(token, secret, [options])

Verifies the integrity of the token.

Argument	Type	Status	Default	Description
token	string	required	-	The token string generated by sign().
secret	string, JsonWebKey, CryptoKey	required	-	The string which was used to sign the payload.
options	string, object	optional	HS256	Either the algorithm string or an object.
options.algorithm	string	optional	HS256	See Available Algorithms
options.clockTolerance	number	optional	0	Clock tolerance in seconds, to help with slighly out of sync systems.
options.throwError	boolean	optional	false	By default this we will only throw integration errors, only set this to true if you want verification errors to be thrown as well.

throws

Throws integration errors and if options.throwError is set to true also throws ALG_MISMATCH, NOT_YET_VALID, EXPIRED or INVALID_SIGNATURE.

return

Returns the decoded token or undefined.

{
    header: {
        alg: "HS256",
        typ: "JWT"
    },
    payload: {
        sub: "1234",
        name: "John Doe",
        email: "john.doe@gmail.com"
    }
}

---

Decode

decode(token)

Just returns the decoded token without verifying verifying it. Please use verify() if you intend to verify it as well.

Argument	Type	Status	Default	Description
token	string	required	-	The token string generated by sign().

return

Returns an object containing header and payload:

{
    header: {
        alg: "HS256",
        typ: "JWT"
    },
    payload: {
        sub: "1234",
        name: "John Doe",
        email: "john.doe@gmail.com"
    }
}

Available Algorithms

• ES256, ES384, ES512
• HS256, HS384, HS512
• RS256, RS384, RS512