feat(common): ConsoleApplicationSecret

A simplel structure to help reading secret files obtained from
https://code.google.com/apis/console

src/common.rs

@@ -30,4 +30,52 @@ impl Str for AuthenticationType {
             AuthenticationType::Device => "https://accounts.google.com/o/oauth2/device/code",
         }
     }
+}
+
+/// Represents either 'installed' or 'web' applications in a json secrets file.
+/// See `ConsoleApplicationSecret` for more information
+#[derive(RustcDecodable, RustcEncodable)]
+pub struct ApplicationSecret {
+    /// The client ID.
+    pub client_id: String,
+    /// The client secret.
+    pub client_secret: String,
+    /// The token server endpoint URI.
+    pub token_uri: String,
+    /// The authorization server endpoint URI.
+    pub auth_uri: String,
+    pub redirect_uris: Vec<String>,
+
+    /// The service account email associated with the client.
+    pub client_email: Option<String>,
+    /// The URL of the public x509 certificate, used to verify the signature on JWTs, such 
+    /// as ID tokens, signed by the authentication provider.
+    pub auth_provider_x509_cert_url: Option<String>,
+    ///  The URL of the public x509 certificate, used to verify JWTs signed by the client.
+    pub client_x509_cert_url: Option<String>
+}
+
+/// A type to facilitate reading and writing the json secret file
+/// as returned by the [google developer console](https://code.google.com/apis/console)
+#[derive(RustcDecodable, RustcEncodable)]
+pub struct ConsoleApplicationSecret {
+    web: Option<ApplicationSecret>,
+    installed: Option<ApplicationSecret>
+}
+
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    const SECRET: &'static str = "{\"installed\":{\"auth_uri\":\"https://accounts.google.com/o/oauth2/auth\",\"client_secret\":\"UqkDJd5RFwnHoiG5x5Rub8SI\",\"token_uri\":\"https://accounts.google.com/o/oauth2/token\",\"client_email\":\"\",\"redirect_uris\":[\"urn:ietf:wg:oauth:2.0:oob\",\"oob\"],\"client_x509_cert_url\":\"\",\"client_id\":\"14070749909-vgip2f1okm7bkvajhi9jugan6126io9v.apps.googleusercontent.com\",\"auth_provider_x509_cert_url\":\"https://www.googleapis.com/oauth2/v1/certs\"}}";
+
+    #[test]
+    fn console_secret() {
+        use rustc_serialize::json;
+        match json::decode::<ConsoleApplicationSecret>(SECRET) {
+            Ok(s) => assert!(s.installed.is_some()),
+            Err(err) => panic!(err),
+        }
+    }
 }

src/lib.rs

@@ -82,5 +82,5 @@ mod common;
 pub use device::{DeviceFlow, PollInformation, PollResult, DeviceFlowHelper, 
                  DeviceFlowHelperDelegate, Retry};
 pub use refresh::{RefreshFlow, RefreshResult};
-pub use common::{Token, AuthenticationType};
+pub use common::{Token, AuthenticationType, ApplicationSecret, ConsoleApplicationSecret};