Oauth2 Client
This library is designed to simplify consuming Oauth2 enabled REST Services. It wraps a restclient and takes care of reauthenticating expired access_tokens when needed.
Flows
Implemented flows are:
- Client Credentials Grant
- Resource Owner Password Credentials Grant
Example
Retrieve a client with access_token using Password Credentials Grant
1> oauth2c:retrieve_access_token(<<"password">>, <<"Url">>, <<"Uid">>, <<"Pwd">>).
{ok, Headers, Client}Retrieve a client with access_token using Client Credentials Grant
2> oauth2c:retrieve_access_token(<<"client_credentials">>, <<"Url">>, <<"Client">>, <<"Secret">>).
{ok, Headers, Client}Microsoft Azure AD: Since parameters are different please use <<"azure_client_credentials">> as Type when retrieving an access token for that service. Be sure to set a Scope if you want to access any of the connected APIs.
2> oauth2c:retrieve_access_token(
<<"azure_client_credentials">>,
<<"some_tenant_specific_oauth_token_endpoint">>,
<<"some_registered_app_id">>,
<<"some_created_key">>,
<<"https://graph.microsoft.com">>).
{ok, Headers, Client}The Opaque Client object is to be used on subsequent requests like:
3> oauth2c:request(get, json, <<"Url">>, [200], Client).
{{ok, Status, Headers, Body} Client2}See restclient for more info on how requests work.
Twitter Example
-module(oauth2c_twitter_example).
-export([ run/0
]).
-define(CONSUMER_SECRET, <<"my_consumer_secret">>).
-define(CONSUMER_KEY, <<"my_consumer_key">>).
-define(OAUTH2_TOKEN_URL, <<"https://api.twitter.com/oauth2/token">>).
-define(USER_TIMELINE_URL(User, StrCount),
<<"https://api.twitter.com/1.1/statuses/user_timeline.json?screen_name="
, User, "&count=", StrCount>>).
-define(APP_LIMITS_URL(Resources),
<< "https://api.twitter.com/1.1/application/rate_limit_status.json?resources="
, Resources>>).
run() ->
application:ensure_all_started(oauth2c),
application:ensure_all_started(ssl),
{ok, _Headers, Client} =
oauth2c:retrieve_access_token(
<<"client_credentials">>, ?OAUTH2_TOKEN_URL, ?CONSUMER_KEY,
?CONSUMER_SECRET),
{{ok, _Status1, _Headers1, Tweets}, Client2} =
oauth2c:request(
get, json, ?USER_TIMELINE_URL("twitterapi", "4"), [200], Client),
io:format("Tweets: ~p~n", [Tweets]),
{{ok, _Status2, _Headers2, Limits}, _Client3} =
oauth2c:request(
get, json, ?APP_LIMITS_URL("help,users,search,statuses"),
[200], Client2),
io:format("Limits: ~p~n", [Limits]),
ok.License
The KIVRA oauth2 library uses an MIT license. So go ahead and do what you want!