Recover from failed segment requests.

* Reject Task Promise if one of its stages fails so that the caller's
  catch handler is invoked.
* Use TypedBind consistently in affected Promise chains.

Closes shaka-project#131

Change-Id: I94fa6688949444212fa0b1edd3a94e0de4d6956f

lib/media/source_buffer_manager.js

@@ -344,12 +344,18 @@ shaka.media.SourceBufferManager.prototype.correct = function(
 shaka.media.SourceBufferManager.prototype.startTask_ = function() {
   shaka.asserts.assert(this.task_);
   this.task_.start();
-  return this.task_.getPromise().then(function() {
-    this.task_ = null;
-  }.bind(this)).catch(function(error) {
-    this.task_ = null;
-    return Promise.reject(error);
-  }.bind(this));
+  return this.task_.getPromise().then(shaka.util.TypedBind(this,
+      function() {
+        this.task_ = null;
+      })
+  ).catch(shaka.util.TypedBind(this,
+      /** @param {*} error */
+      function(error) {
+        shaka.log.v1('The task failed!');
+        this.task_ = null;
+        return Promise.reject(error);
+      })
+  );
 };
 
 

lib/media/stream.js

@@ -460,6 +460,7 @@ shaka.media.Stream.prototype.onUpdate_ = function() {
         var recoverableErrors = [0, 404, 410];
         if (error.type == 'net' &&
             recoverableErrors.indexOf(error.xhr.status) != -1) {
+          shaka.log.debug('Calling onUpdate_() in 5 seconds...');
           // Depending on application policy, this could be recoverable,
           // so set a timer on the supposition that the app might not end
           // playback.

lib/util/task.js

@@ -157,38 +157,46 @@ shaka.util.Task.prototype.startNextStage_ = function(arg) {
     this.aborter_ = null;
   }
 
-  done.then(function(arg) {
-    if (this.abortedPromise_) {
-      // Aborted in between stages or in a way that didn't fail the stage.
-      // Clean up.
-      this.stages_ = [];
-      this.aborter_ = null;
-      this.completeAbort_();
-      return;
-    }
-
-    // Throw away the stage we just completed.
-    this.stages_.shift();
-
-    if (this.stages_.length) {
-      // Start the next stage.
-      this.startNextStage_(arg);
-    } else {
-      // All done.  Clean up.
-      this.taskPromise_.resolve(arg);
-      this.aborter_ = null;
-    }
-  }.bind(this)).catch(function(error) {
-    // Task failed.  Clean up.
-    this.stages_ = [];
-    this.aborter_ = null;
-
-    if (this.abortedPromise_) {
-      // Aborted during a stage in a way that failed the stage.
-      // Resolve the aborted promise.
-      this.completeAbort_();
-    }
-  }.bind(this));
+  done.then(shaka.util.TypedBind(this,
+      /** @param {?} arg */
+      function(arg) {
+        if (this.abortedPromise_) {
+          // Aborted in between stages or in a way that didn't fail the stage.
+          // Clean up.
+          this.stages_ = [];
+          this.aborter_ = null;
+          this.completeAbort_();
+          return;
+        }
+
+        // Throw away the stage we just completed.
+        this.stages_.shift();
+
+        if (this.stages_.length) {
+          // Start the next stage.
+          this.startNextStage_(arg);
+        } else {
+          // All done.  Clean up.
+          this.taskPromise_.resolve(arg);
+          this.aborter_ = null;
+        }
+      })
+  ).catch(shaka.util.TypedBind(this,
+      /** @param {*} error */
+      function(error) {
+        // Task failed.  Clean up.
+        this.stages_ = [];
+        this.aborter_ = null;
+
+        if (this.abortedPromise_) {
+          // Aborted during a stage in a way that failed the stage.
+          // Resolve the aborted promise.
+          this.completeAbort_();
+        } else {
+          this.taskPromise_.reject(error);
+        }
+      })
+  );
 };
 
 

spec/task_spec.js

@@ -287,5 +287,32 @@ describe('Task', function() {
       });
     });
   });
+
+  describe('getPromise', function() {
+    it('is rejected when a stage fails', function(done) {
+      var p = new shaka.util.PublicPromise();
+      t.append(function() { return [p]; });
+      t.start();
+
+      var timer = setTimeout(function() {
+        p.resolve();
+      }, 1500);
+
+      setTimeout(function() {
+        clearTimeout(timer);
+        var error = new Error('This is a test error.');
+        error.type = 'test';
+        p.reject(error);
+      }, 500);
+
+      t.getPromise().then(function() {
+        // The first stage should never complete.
+        fail();
+      }).catch(function(error) {
+        expect(error.type).toBe('test');
+        done();
+      });
+    });
+  });
 });