Added support for grant type password #57

simple_auth/lib/simple_auth.dart

@@ -19,6 +19,8 @@ export 'src/oauth/oauthApi.dart';
 export 'src/oauth/oauthApiKeyApi.dart';
 export 'src/oauth/oauthAuthenticator.dart';
 export 'src/oauth/oauthResponse.dart';
+export 'src/oauth/oauthPasswordApi.dart';
+export 'src/oauth/oauthPasswordAuthenticator.dart';
 export 'src/providers/amazon.dart';
 export 'src/providers/azureAD.dart';
 export 'src/providers/azureADV2.dart';

simple_auth/lib/src/annotations.dart

@@ -72,6 +72,19 @@ class OAuthApiDeclaration extends ApiDeclaration {
       : super(name, baseUrl: baseUrl);
 }
 
+@immutable
+class OAuthPasswordApiDeclaration extends ApiDeclaration {
+  final String clientId;
+  final String clientSecret;
+  final String tokenUrl;
+  final String loginUrl;
+  const OAuthPasswordApiDeclaration(String name, this.clientId,
+      this.clientSecret, this.loginUrl , this.tokenUrl,
+      {String baseUrl = "/"})
+      : super(name, baseUrl: baseUrl);
+}
+
+
 @immutable
 class AmazonApiDeclaration extends ApiDeclaration {
   final String clientId;

simple_auth/lib/src/oauth/oauthPasswordApi.dart

@@ -0,0 +1,96 @@
+import "dart:async";
+import "package:simple_auth/simple_auth.dart";
+import "package:http/http.dart" as http;
+import "dart:convert" as convert;
+
+typedef void ShowOauthPasswordAuthenticator(
+    OauthPasswordAuthenticator authenticator);
+
+class OAuthPasswordApi extends OAuthApi {
+  String loginUrl;
+  String tokenUrl;
+  OauthPasswordAuthenticator currentAuthenticator;
+  static ShowOauthPasswordAuthenticator sharedShowAuthenticator;
+
+
+  OAuthPasswordApi(String identifier, 
+      this.loginUrl,
+      this.tokenUrl,
+      String clientId,
+      String clientSecret,
+      {List<String> scopes,
+      http.Client client,
+      Converter converter,
+      AuthStorage authStorage})
+      : super.fromIdAndSecret(identifier, clientId, clientSecret,
+            client: client,
+            scopes: scopes,
+            converter: converter,
+            authStorage: authStorage) {
+        this.scopesRequired = false;
+      }
+
+  OAuthAccount get currentOauthAccount => currentAccount as OAuthAccount;
+
+
+  @override
+  Future<Account> performAuthenticate() async {
+    if (scopesRequired && (scopes?.length ?? 0) == 0) {
+      throw Exception("Scopes are required");
+    }
+    OAuthAccount account =
+        currentOauthAccount ?? await loadAccountFromCache<OAuthAccount>();
+    if (account != null &&
+        ((account.refreshToken?.isNotEmpty ?? false) ||
+            (account.expiresIn != null && account.expiresIn <= 0))) {
+      var valid = account.isValid();
+      if (!valid || forceRefresh ?? false) {
+        //If there is no interent, give them the current expired account
+        if (!await pingUrl(tokenUrl)) {
+          return account;
+        }
+        if (await refreshAccount(account))
+          account = currentOauthAccount ?? loadAccountFromCache<OAuthAccount>();
+      }
+      if (account.isValid()) {
+        saveAccountToCache(account);
+        currentAccount = account;
+        return account;
+      }
+    }
+
+    var _authenticator = getAuthenticator();
+    await _authenticator.resetAuthenticator();
+    if (sharedShowAuthenticator != null)
+      sharedShowAuthenticator(_authenticator);
+    else
+      throw new Exception(
+          "You are required to implement the 'showAuthenticator or sharedShowAuthenticator");
+    var token = await _authenticator.getAuthCode();
+    if (token?.isEmpty ?? true) {
+      throw new Exception("Null Token");
+    }
+    account = await getAccountFromAuthCode(_authenticator);
+    saveAccountToCache(account);
+    currentAccount = account;
+    return account;
+  }
+
+
+  @override  
+  OauthPasswordAuthenticator getAuthenticator() => OauthPasswordAuthenticator(identifier, clientId, clientSecret,loginUrl , tokenUrl, baseUrl, redirectUrl, scopes);
+
+
+  @override
+  Future<OAuthAccount> getAccountFromAuthCode(
+      WebAuthenticator authenticator) async {
+    var auth = authenticator as OauthPasswordAuthenticator;
+    return OAuthAccount(identifier,
+        created: DateTime.now().toUtc(),
+        expiresIn: auth.token.expiresIn,
+        refreshToken: auth.token.refreshToken,
+        scope: authenticator.scope ?? List<String>(),
+        tokenType: auth.token.tokenType,
+        token: auth.token.accessToken);
+  }
+}

simple_auth/lib/src/oauth/oauthPasswordAuthenticator.dart

@@ -0,0 +1,75 @@
+import 'dart:convert';
+
+import "package:simple_auth/simple_auth.dart";
+import "package:http/http.dart" as http;
+import "dart:async";
+
+class OauthPasswordAuthenticator extends OAuthAuthenticator {
+  String loginUrl;
+  AuthTokenClass token;
+
+  OauthPasswordAuthenticator(String identifier, String clientId, String clientSecret,
+      this.loginUrl, tokenUrl, String baseUrl, String redirectUrl, List<String> scopes)
+      : super(identifier, clientId, clientSecret, tokenUrl, baseUrl,
+            redirectUrl) {}
+
+  Future<bool> verifyCredentials(String username, String password) async {
+    try {
+      if (username?.isEmpty ?? true) throw new Exception("Invalid Username");
+      if (password?.isEmpty ?? true) throw new Exception("Invalid Password");
+
+      Map<String, dynamic> body = {
+        'username': username,
+        'password': password,
+        'grant_type': "password"
+      };
+
+      var headers = {'Content-Type' : 'application/x-www-form-urlencoded'};
+      var req = await http.post(loginUrl, body: body , headers: headers,encoding: Encoding.getByName("utf-8"));
+
+      var success = req.statusCode >= 200 && req.statusCode < 300;
+      if (!success) return false;
+
+
+      var token = new AuthTokenClass.fromJson(json.decode(req.body));
+        if(token.accessToken?.isNotEmpty ?? false) {
+        this.token = token;
+        foundAuthCode(token.accessToken);
+        return true;      
+      }
+      return false;
+
+    } catch (e) {
+      return false;
+    }
+  }
+
+
+    ///Gets the data that will be posted to swap the auth code for an auth token
+  Future<Map<String, dynamic>> getTokenPostData(String clientSecret) async {
+    var data = {
+      "grant_type": "password",
+      "client_id": clientId,
+      "client_secret": clientSecret
+    };
+    return data;
+  }
+}
+
+class AuthTokenClass {
+  String accessToken;
+  String refreshToken;
+  String tokenType;
+  int expiresIn;
+
+  AuthTokenClass({this.accessToken,this.refreshToken,this.tokenType,this.expiresIn});
+
+  factory AuthTokenClass.fromJson(Map<String,dynamic> json) {
+    return AuthTokenClass(
+      accessToken : json['access_token'],
+      refreshToken : json['refresh_token'],
+      tokenType: json['token_type'],
+      expiresIn: json['expires_in'],
+    );
+  }
+}

simple_auth_flutter/lib/oauth_password_login_page.dart

@@ -0,0 +1,123 @@
+import 'package:flutter/material.dart';
+import 'package:simple_auth/simple_auth.dart';
+
+class OauthPasswordLoginPage extends StatefulWidget {
+  static String defaultLogo;
+  final OauthPasswordAuthenticator authenticator;
+  OauthPasswordLoginPage(this.authenticator);
+  static String tag = 'grant-password-login-page';
+  @override
+  _LoginPageState createState() => new _LoginPageState();
+}
+
+class _LoginPageState extends State<OauthPasswordLoginPage> {
+  final emailController = TextEditingController();
+  final passwordController = TextEditingController();
+  @override
+  Widget build(BuildContext context) {
+    final logo = Hero(
+      tag: 'hero',
+      child: CircleAvatar(
+        backgroundColor: Colors.transparent,
+        radius: 48.0,
+        child: (OauthPasswordLoginPage.defaultLogo?.isEmpty ?? true)
+            ? Icon(Icons.supervised_user_circle)
+            : Image.asset(OauthPasswordLoginPage.defaultLogo),
+      ),
+    );
+
+    final email = TextFormField(
+      controller: emailController,
+      keyboardType: TextInputType.emailAddress,
+      autofocus: true,
+      decoration: InputDecoration(
+        hintText: 'Email',
+        contentPadding: EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
+        border: OutlineInputBorder(borderRadius: BorderRadius.circular(32.0)),
+      ),
+    );
+
+    final password = TextFormField(
+      controller: passwordController,
+      autofocus: false,
+      obscureText: true,
+      decoration: InputDecoration(
+        hintText: 'Password',
+        contentPadding: EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
+        border: OutlineInputBorder(borderRadius: BorderRadius.circular(32.0)),
+      ),
+    );
+
+    final loginButton = Padding(
+      padding: EdgeInsets.symmetric(vertical: 16.0),
+      child: Material(
+        borderRadius: BorderRadius.circular(30.0),
+        shadowColor: Colors.lightBlueAccent.shade100,
+        elevation: 5.0,
+        child: MaterialButton(
+          minWidth: 200.0,
+          height: 42.0,
+          onPressed: () async {
+            try {
+              bool success = await widget.authenticator.verifyCredentials(
+                  emailController.text, passwordController.text);
+              if (success) Navigator.pop(context);
+            } catch (ex) {
+              var alert =
+                  new AlertDialog(content: new Text(ex), actions: <Widget>[
+                new FlatButton(
+                    child: const Text("Ok"),
+                    onPressed: () {
+                      Navigator.pop(context);
+                    })
+              ]);
+              showDialog(
+                  context: context, builder: (BuildContext context) => alert);
+            }
+          },
+          color: Colors.lightBlueAccent,
+          child: Text('Log In', style: TextStyle(color: Colors.white)),
+        ),
+      ),
+    );
+
+    return Scaffold(
+      appBar: new AppBar(
+        title: Text(widget.authenticator.title),
+        actions: widget.authenticator.allowsCancel
+            ? <Widget>[
+                new IconButton(
+                  icon: new Icon(Icons.cancel),
+                  onPressed: () {
+                    widget.authenticator.cancel();
+                    Navigator.pop(context);
+                  },
+                )
+              ]
+            : null,
+      ),
+      backgroundColor: Colors.white,
+      body: Center(
+        child: ListView(
+          shrinkWrap: true,
+          padding: EdgeInsets.only(left: 24.0, right: 24.0),
+          children: <Widget>[
+            logo,
+            SizedBox(height: 48.0),
+            email,
+            SizedBox(height: 8.0),
+            password,
+            SizedBox(height: 24.0),
+            loginButton,
+          ],
+        ),
+      ),
+    );
+  }
+
+  @override
+  void dispose() {
+    widget.authenticator.cancel();
+    super.dispose();
+  }
+}

simple_auth_flutter_example/lib/main.dart

@@ -94,6 +94,15 @@ class _MyHomePageState extends State<MyHomePage> {
 
   final simpleAuth.BasicAuthApi basicApi = new simpleAuth.BasicAuthApi(
       "github-basic", "https://api.github.com/user");
+
+  final simpleAuth.OAuthPasswordApi oauthPasswordApi = new simpleAuth
+          .OAuthPasswordApi(
+      "oauth-password",
+      "loginUrl",
+      "tokenUrl",
+      "clientId",
+      "clientSecret");
+
   final simpleAuth.InstagramApi instagramApi = new simpleAuth.InstagramApi(
       "instagram", "clientId", "clientSecret", "redirecturl");
 
@@ -311,6 +320,32 @@ class _MyHomePageState extends State<MyHomePage> {
               showMessage("Logged out");
             },
           ),
+          ListTile(
+            title: Text(
+              "Oauth Grant Password",
+              style: Theme.of(context).textTheme.headline,
+            ),
+          ),
+          ListTile(
+            leading: Icon(Icons.launch),
+            title: Text('Login'),
+            onTap: () async {
+              try {
+                var success = await oauthPasswordApi.authenticate();
+                showMessage("Logged in success: $success");
+              } catch (e) {
+                showError(e);
+              }
+            },
+          ),
+          ListTile(
+            leading: Icon(Icons.delete),
+            title: Text('Logout'),
+            onTap: () async {
+              await oauthPasswordApi.logOut();
+              showMessage("Logged out");
+            },
+          ),
           ListTile(
             title: Text(
               "Instagram OAuth",