Adding Document.analyze_sentiment() in language.

gcloud/language/document.py

@@ -18,6 +18,7 @@
 """
 
 from gcloud.language.entity import Entity
+from gcloud.language.sentiment import Sentiment
 
 
 DEFAULT_LANGUAGE = 'en-US'
@@ -146,3 +147,19 @@ def analyze_entities(self):
             method='POST', path='analyzeEntities', data=data)
         return [Entity.from_api_repr(entity)
                 for entity in api_response['entities']]
+
+    def analyze_sentiment(self):
+        """Analyze the sentiment in the current document.
+
+        .. _analyzeSentiment: https://cloud.google.com/natural-language/\
+                              reference/rest/v1beta1/documents/analyzeSentiment
+
+        See `analyzeSentiment`_.
+
+        :rtype: :class:`.Sentiment`
+        :returns: The sentiment of the current document.
+        """
+        data = {'document': self._to_dict()}
+        api_response = self.client.connection.api_request(
+            method='POST', path='analyzeSentiment', data=data)
+        return Sentiment.from_api_repr(api_response['documentSentiment'])

gcloud/language/sentiment.py

@@ -39,3 +39,17 @@ class Sentiment(object):
     def __init__(self, polarity, magnitude):
         self.polarity = polarity
         self.magnitude = magnitude
+
+    @classmethod
+    def from_api_repr(cls, payload):
+        """Convert an Sentiment from the JSON API into a :class:`Sentiment`.
+
+        :param payload: dict
+        :type payload: The value from the backend.
+
+        :rtype: :class:`Sentiment`
+        :returns: The sentiment parsed from the API representation.
+        """
+        polarity = payload['polarity']
+        magnitude = payload['magnitude']
+        return cls(polarity, magnitude)

gcloud/language/test_document.py

@@ -167,6 +167,34 @@ def test_analyze_entities(self):
         self.assertEqual(req['path'], 'analyzeEntities')
         self.assertEqual(req['method'], 'POST')
 
+    def test_analyze_sentiment(self):
+        from gcloud.language.sentiment import Sentiment
+
+        content = 'All the pretty horses.'
+        polarity = 1
+        magnitude = 0.6
+        response = {
+            'documentSentiment': {
+                'polarity': polarity,
+                'magnitude': magnitude,
+            },
+            'language': 'en',
+        }
+        connection = _Connection(response)
+        client = _Client(connection=connection)
+        document = self._makeOne(client, content)
+
+        sentiment = document.analyze_sentiment()
+        self.assertIsInstance(sentiment, Sentiment)
+        self.assertEqual(sentiment.polarity, polarity)
+        self.assertEqual(sentiment.magnitude, magnitude)
+
+        # Verify the request.
+        self.assertEqual(len(connection._requested), 1)
+        req = connection._requested[0]
+        self.assertEqual(req['path'], 'analyzeSentiment')
+        self.assertEqual(req['method'], 'POST')
+
 
 class _Connection(object):
 

gcloud/language/test_sentiment.py

@@ -30,3 +30,15 @@ def test_constructor(self):
         sentiment = self._makeOne(polarity, magnitude)
         self.assertEqual(sentiment.polarity, polarity)
         self.assertEqual(sentiment.magnitude, magnitude)
+
+    def test_from_api_repr(self):
+        klass = self._getTargetClass()
+        polarity = -1
+        magnitude = 5.55
+        payload = {
+            'polarity': polarity,
+            'magnitude': magnitude,
+        }
+        sentiment = klass.from_api_repr(payload)
+        self.assertEqual(sentiment.polarity, polarity)
+        self.assertEqual(sentiment.magnitude, magnitude)