Client Obtain Token

Code Flow

Code Flow would be the most basic flow to get an access token for server-side apps.

# Authorization Request
authorization_uri = client.authorization_uri(
  scope: [:profile, :email]
)
`open "#{authorization_uri}"`

# Authorization Response
puts "# Authorization Code"
code = gets.strip

# Token Request
client.authorization_code = code
client.access_token! # => Rack::OAuth2::AccessToken::Bearer (or other Rack::OAuth2::AccessTokens subclass)

rack-oauth2 uses Authorization header for Client Authentication as default. If your OAuth Server doesn't support Basic Auth for Client Authentication and require including client_secret in request body, do

client.access_token! :body

Client Credentials Flow (a.k.a 2-legged)

Client Credentials Flow doesn't require any user interaction.