jwx

README

github.com/lestrrat-go/jwx

Various libraries implementing various JWx technologies. Please click on the package names in the table below to find the synopsis/description for each package.

Package name	Notes
jwt	RFC 7519
jwk	RFC 7517 + RFC 7638
jwa	RFC 7518
jws	RFC 7515 + RFC 7797
jwe	RFC 7516

How to Use

• API documentation
• How-to style documentation
• Runnable Examples

Description

History

My goal was to write a server that heavily uses JWK and JWT. At first glance the libraries that already exist seemed sufficient, but soon I realized that

1. To completely implement the protocols, I needed the entire JWT, JWK, JWS, JWE (and JWA, by necessity).
2. Most of the libraries that existed only deal with a subset of the various JWx specifications that were necessary to implement their specific needs

For example, a certain library looks like it had most of JWS, JWE, JWK covered, but then it lacked the ability to include private claims in its JWT responses. Another library had support of all the private claims, but completely lacked in its flexibility to generate various different response formats.

Because I was writing the server side (and the client side for testing), I needed the entire JOSE toolset to properly implement my server, and they needed to be flexible enough to fulfill the entire spec that I was writing.

So here's github.com/lestrrat-go/jwx. This library is extensible, customizable, and hopefully well organized to the point that it is easy for you to slice and dice it.

Why would I use this library?

There are several other major Go modules that handle JWT and related data formats, so why should you use this library?

From a purely functional perspective, the only major difference is this: Whereas most other projects only deal with what they seem necessary to handle JWTs, this module handles the entire spectrum of JWS, JWE, JWK, and JWT.

That is, if you need to not only parse JWTs, but also to control JWKs, or if you need to handle payloads that are NOT JWTs, you should probably consider using this module.

Next, from an implementation perspective, this module differs significantly from others in that it tries very hard to expose only the APIs, and not the internal data. For example, individual JWT claims are not accessible through struct field lookups. You need to use one of the getter methods.

This is because this library takes the stance that the end user is fully capable and even willing to shoot themselves on the foot when presented with a lax API. By making sure that users do not have access to open structs, we can protect users from doing silly things like creating incomplete structs, or access the structs concurrently without any protection. This structure also allows us to put extra smarts in the structs, such as doing the right thing when you want to parse / write custom fields (this module does not require the user to specify alternate structs to parse objects with custom fields)

In the end I think it comes down to your usage pattern, and priorities. Some general guidelines that come to mind are:

• If you want a single library to handle everything JWx, such as using JWE, JWK, JWS, handling auto-refreshing JWKs, use this module.
• If you want to honor all possible custom fields transparently, use this module.
• If you want a standardized clean API, use this module.

Otherwise, feel free to choose something else.

Command Line Tool

Since v1.1.1 we have a command line tool jwx (*). With jwx you can create JWKs (from PEM files, even), sign and verify JWS message, encrypt and decrypt JWE messages, etc.

(*) Okay, it existed since a long time ago, but it was never useful.

Installation

go install github.com/lestrrat-go/jwx/cmd/jwx

Caveats

Backwards Compatibility Notice

Users of github.com/lestrrat/go-jwx

Uh, why are you using such an ancient version? You know that repository is archived for a reason, yeah? Please use the new version.

Pre-1.0.0 users

The API has been reworked quite substantially between pre- and post 1.0.0 releases. Please check out the Changes file (or the diff, if you are into that sort of thing)

v1.0.x users

The API has gone under some changes for v1.1.0. If you are upgrading, you might want to read the relevant parts in the Changes file.

Contributions

Issues

For bug reports and feature requests, please try to follow the issue templates as much as possible. For either bug reports or feature requests, failing tests are even better.

Pull Requests

Please make sure to include tests that excercise the changes you made.

If you are editing auto-generated files (those files with the _gen.go prefix, please make sure that you do the following:

1. Edit the generator, not the generated files (e.g. internal/cmd/genreadfile/main.go)
2. Run make generate (or go generate) to generate the new code
3. Commit both the generator and the generated files

Discussions / Usage

Please try discussions first.

Credits

• Work on this library was generously sponsored by HDE Inc (https://www.hde.co.jp)
• Lots of code, especially JWE was taken from go-jose library (https://github.com/square/go-jose)
• Lots of individual contributors have helped this project over the years. Thank each and everyone of you very much.

Documentation

Overview

Package jwx contains tools that deal with the various JWx (JOSE) technologies such as JWT, JWS, JWE, etc in Go.

JWS (https://tools.ietf.org/html/rfc7515)
JWE (https://tools.ietf.org/html/rfc7516)
JWK (https://tools.ietf.org/html/rfc7517)
JWA (https://tools.ietf.org/html/rfc7518)
JWT (https://tools.ietf.org/html/rfc7519)

The primary focus of this library tool set is to implement the extremely flexible OAuth2 / OpenID Connect protocols.

Examples are stored in a separate Go module (to avoid adding dependencies to this module), and thus does not appear in the online documentation for this module. You can find the examples in Github at https://github.com/lestrrat-go/jwx/examples

You can find more high level documentation at Github (https://github.com/lestrrat-go/jwx)

Index

• func DecoderSettings(options ...JSONOption)
• type FormatKind
  • func GuessFormat(payload []byte) FormatKind
  • func (i FormatKind) String() string
• type JSONOption
  • func WithUseNumber(b bool) JSONOption
• type Option

Functions

func DecoderSettings

func DecoderSettings(options ...JSONOption)

DecoderSettings gives you a access to configure the "encoding/json".Decoder used to decode JSON objects within the jwx framework.

Types

type FormatKind

type FormatKind int

const (
	UnknownFormat FormatKind = iota
	JWE
	JWS
	JWK
	JWKS
	JWT
)

func GuessFormat

func GuessFormat(payload []byte) FormatKind

GuessFormat is used to guess the format the given payload is in using heuristics. See the type FormatKind for a full list of possible types.

This may be useful in determining your next action when you may encounter a payload that could either be a JWE, JWS, or a plain JWT.

Because JWTs are almost always JWS signed, you may be thrown off if you pass what you think is a JWT payload to this function. If the function is in the "Compact" format, it means it's a JWS signed message, and its payload is the JWT. Therefore this function will reuturn JWS, not JWT.

This function requires an extra parsing of the payload, and therefore may be inefficient if you call it every time before parsing.

func (FormatKind) String

func (i FormatKind) String() string

type JSONOption

type JSONOption interface {
	Option
	// contains filtered or unexported methods
}

func WithUseNumber

func WithUseNumber(b bool) JSONOption

WithUseNumber controls whether the jwx package should unmarshal JSON objects with the "encoding/json".Decoder.UseNumber feature on.

Default is false.

type Option

type Option = option.Interface