### jwt — Erlang JWT Library
---
[](https://hex.pm/packages/jwt)
---
JWT is a simple authorization token [format](http://jwt.io/) based on JSON.
#### Installation
If you use rebar (supports both 2 and 3 versions) or mix (Elixir):
```erlang
% in rebar.config for rebar3
{deps, [{jwt}]}.
% or for rebar2
{deps, [{jwt, ".*", {git, "https://github.com/artemeff/jwt", {tag, "0.1.0"}}}]}
```
```elixir
% mix.exs
def deps do
[{:jwt, "~> 0.1"}]
end
```
Or use it as git dependency.
#### Usage example
```erlang
%% Create JWT token
> application:ensure_all_started(jwt).
> Key = <<"supas3cri7">>.
> Claims = [
{user_id, 42},
{user_name, <<"Bob">>}
].
> {ok, Token} = jwt:encode(<<"HS256">>, Claims, Key).
%% or with expiration
> ExpirationSeconds = 86400.
> {ok, Token} = jwt:encode(<<"HS256">>, Claims, ExpirationSeconds, Key).
%% Parse JWT token
> {ok, Claims} = jwt:decode(Token, Key).
%% Issuer specific keys workflow
%% The encoder just knows about itself
> Issuer = <<"iss1">>.
> IssuerKey = <<"Issuer-1-Key">>.
> Claims2 = [
{iss, Issuer},
{user_id, 42},
{user_name, <<"Bob">>}
].
> {ok, Token2} = jwt:encode(<<"HS256">>, Claims, ExpirationSeconds, IssuerKey).
%% Decoder Workflow
%% The decoder knows about all encoder keys (issuer specific)
> IssuerKeyMapping = #{ Issuer => IssuerKey,
<<"iss2">> => <<"Issuer2Key">>}.
> {ok, Claims} = jwt:decode(Token, <<"default-key">>, IssuerKeyMapping).
```
---
### Contributing
1. Fork it
2. Create your feature branch (`git checkout -b my-new-feature`)
3. Commit your changes (`git commit -am 'add some feature'`)
4. Push to the branch (`git push origin my-new-feature`)
5. Create new Pull Request
