OAuth2::Client

An OAuth2 client.

For a quick example of how to authenticate an HTTP::Client with OAuth2 if you already have an access token, check the OAuth2 module description.

This class also provides methods to build authorize URIs and get access tokens with different methods, as specified by RFC 6749.

Example

require "oauth2"

client_id = "some_client_id"
client_secret = "some_client_secret"
redirect_uri = "http://some.callback"

# Create oauth client, optionally pass custom URIs if needed,
# if the authorize or token URIs are not the standard ones
# (they can also be absolute URLs)
oauth2_client = OAuth2::Client.new("api.example.com", client_id, client_secret,
  redirect_uri: redirect_uri)

# Build an authorize URI
authorize_uri = oauth2_client.get_authorize_uri

# Redirect the user to `authorize_uri`...
#
# ...
#
# When http://some.callback is hit, once the user authorized the access,
# we resume our logic to finally get an access token. The callback URL
# should receive an `authorization_code` parameter that we need to use.
authorization_code = request.params["code"]

# Get the access token
access_token = oauth2_client.get_access_token_using_authorization_code(authorization_code)

# Probably save the access token for reuse... This can be done
# with `to_json` and `from_json`.

# Use the token to authenticate an HTTP::Client
client = HTTP::Client.new("api.example.com", tls: true)
access_token.authenticate(client)

# And do requests as usual
client.get "/some_path"

# If the token expires, we can refresh it
new_access_token = oauth2_client.get_access_token_using_refresh_token(access_token.refresh_token)

You can also use an OAuth2::Session to automatically refresh expired tokens before each request.