Fixed scopes on Android (#29) and added Slack insructions to README (ios only)

Author: auser

README.md

@@ -6,6 +6,7 @@ The `react-native-oauth` library provides an interface to OAuth 1.0 and OAuth 2.
 * Facebook
 * Google
 * Github
+* Slack (iOS)
 
 ## TL;DR;
 
@@ -328,6 +329,35 @@ const config =  {
 }
 ```
 
+## Slack (iOS)
+
+Currently implemented only for iOS, Slack support is ready to go. We'll need to create an app first. Head to the slack developer docs at [https://slack.com/developers](https://slack.com/developers). 
+
+![](./resources/slack/dev.png)
+
+Click on the Getting Started button:
+
+![](./resources/slack/getting_started.png)
+
+ From here, find the `create an app` link:
+
+![](./resources/slack/create.png)
+
+ Take note of the `client_id` and the `client_secret`. We'll place these in our configuration object just like so:
+
+```javascript
+const config =  {
+  slack: {
+    client_id: 'YOUR_CLIENT_ID',
+    client_secret: 'YOUR_CLIENT_SECRET'
+  }
+}
+```
+
+Lastly, Slack requires us to add a redirect_url. By default, the callback_url pattern is `${app_name}://oauth`, so make sure to add your redirect_url where it asks for them before starting to work with the API.
+
+![](./resources/slack/redirect.png)
+
 ## Authenticating against our providers
 
 We can use the manager in our app using the `authorize()` method on the manager.
@@ -364,6 +394,16 @@ The `resp` object is set as follows:
 }
 ```
 
+The second argument accepts an object where we can ask for additional scopes, override default values, etc. 
+
+```javascript
+manager.authorize('google', {scopes: 'email,profile'})
+  .then(resp => console.log(resp))
+  .catch(err => console.log(err));
+```
+
+* Scopes are a list of scopes _comma separated_ as a string. 
+
 ## Calling a provider's API
 
 We can use OAuthManager to make requests to endpoints from our providers as well. For instance, let's say we want to get a user's time line from twitter. We would make the request to the url [https://api.twitter.com/1.1/statuses/user_timeline.json](https://api.twitter.com/1.1/statuses/user_timeline.json)

android/src/main/java/io/fullstack/oauth/OAuthManagerProviders.java

@@ -62,7 +62,7 @@ private static OAuth10aService twitterService(final HashMap cfg, final String ca
 
     String scopes = (String) cfg.get("scopes");
     if (scopes != null) {
-      builder.scopes(scopes);
+      builder.scope(scopes);
     }
 
     if (callbackUrl != null) {
@@ -87,6 +87,11 @@ private static OAuth20Service facebookService(final HashMap cfg, final String ca
       .apiSecret(clientSecret)
       .state(state)
       .debug();
+
+    String scopes = (String) cfg.get("scopes");
+    if (scopes != null) {
+      builder.scope(scopes);
+    }
 
     if (callbackUrl != null) {
       builder.callback(callbackUrl);
@@ -104,9 +109,10 @@ private static OAuth20Service googleService(final HashMap cfg, final String call
     } else {
       state = TAG + new Random().nextInt(999_999);
     }
+
     String scope = "profile";
-    if (cfg.containsKey("scope")) {
-      scope = (String) cfg.get("scope");
+    if (cfg.containsKey("scopes")) {
+      scope = (String) cfg.get("scopes");
     }
 
     ServiceBuilder builder = new ServiceBuilder()
@@ -133,8 +139,8 @@ private static OAuth20Service githubService(final HashMap cfg, final String call
       state = TAG + new Random().nextInt(999_999);
     }
     String scope = "profile";
-    if (cfg.containsKey("scope")) {
-      scope = (String) cfg.get("scope");
+    if (cfg.containsKey("scopes")) {
+      scope = (String) cfg.get("scopes");
     }
 
     ServiceBuilder builder = new ServiceBuilder()
@@ -148,8 +154,6 @@ private static OAuth20Service githubService(final HashMap cfg, final String call
       builder.callback(callbackUrl);
     }
 
-    Log.d(TAG, "builder ---> " + callbackUrl);
-
     return builder.build(GitHubApi.instance());
   }
 }