jwt

JSON Web Token for Go RFC 7519, also see jwt.io for more.

The latest version is v3.

Rationale

There are many JWT libraries, but many of them are hard to use (unclear or fixed API), not optimal (unneeded allocations + strange API). This library addresses all these issues. It's simple to read, to use, memory and CPU conservative.

Features

• Simple API.
• Clean and tested code.
• Optimized for speed.
• Concurrent-safe.
• Dependency-free.
• All well-known algorithms are supported
  • HMAC (HS)
  • RSA (RS)
  • RSA-PSS (PS)
  • ECDSA (ES)
  • EdDSA (EdDSA)
  • or your own!

Install

Go version 1.13+

GO111MODULE=on go get github.com/cristalhq/jwt/v3

Example

Build new token:

// create a Signer (HMAC in this example)
key := []byte(`secret`)
signer, err := jwt.NewSignerHS(jwt.HS256, key)
checkErr(err)

// create claims (you can create your own, see: Example_BuildUserClaims)
claims := &jwt.RegisteredClaims{
    Audience: []string{"admin"},
    ID:       "random-unique-string",
}

// create a Builder
builder := jwt.NewBuilder(signer)

// and build a Token
token, err := builder.Build(claims)
checkErr(err)

// here is token as byte slice
var _ []byte = token.Bytes() // or just token.String() for string

Parse and verify token:

// create a Verifier (HMAC in this example)
key := []byte(`secret`)
verifier, err := jwt.NewVerifierHS(jwt.HS256, key)
checkErr(err)

// parse a Token (by example received from a request)
tokenStr := `<header.payload.signature>`
token, err := jwt.ParseString(tokenStr)
checkErr(err)

// and verify it's signature
err = verifier.Verify(token.Payload(), token.Signature())
checkErr(err)

// also you can parse and verify together
newToken, err := jwt.ParseAndVerifyString(tokenStr, verifier)
checkErr(err)

// get standard claims
var newClaims jwt.StandardClaims
errClaims := json.Unmarshal(newToken.RawClaims(), &newClaims)
checkErr(errClaims)

// verify claims as you 
var _ bool = newClaims.IsForAudience("admin")
var _ bool = newClaims.IsValidAt(time.Now())

Also see examples: example_test.go.

Documentation

See these docs.

License

MIT License.