Rename and move _JSONSpeechAPI to HTTPSpeechAPI. (#2979)

* Rename and move _JSONSpeechAPI to HTTPSpeechAPI.

speech/google/cloud/speech/_http.py

@@ -0,0 +1,210 @@
+# Copyright 2017 Google Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+"""HTTP module for managing Speech API requests."""
+
+from base64 import b64encode
+
+from google.cloud._helpers import _bytes_to_unicode
+from google.cloud._helpers import _to_bytes
+
+from google.cloud.speech.result import Result
+from google.cloud.speech.operation import Operation
+
+
+class HTTPSpeechAPI(object):
+    """Speech API for interacting with the HTTP version of the API.
+
+    :type client: :class:`google.cloud.core.client.Client`
+    :param client: Instance of a ``Client`` object.
+    """
+    def __init__(self, client):
+        self._client = client
+        self._connection = client._connection
+
+    def async_recognize(self, sample, language_code=None,
+                        max_alternatives=None, profanity_filter=None,
+                        speech_context=None):
+        """Asychronous Recognize request to Google Speech API.
+
+        .. _async_recognize: https://cloud.google.com/speech/reference/\
+                             rest/v1beta1/speech/asyncrecognize
+
+        See `async_recognize`_.
+
+        :type sample: :class:`~google.cloud.speech.sample.Sample`
+        :param sample: Instance of ``Sample`` containing audio information.
+
+        :type language_code: str
+        :param language_code: (Optional) The language of the supplied audio as
+                              BCP-47 language tag. Example: ``'en-GB'``.
+                              If omitted, defaults to ``'en-US'``.
+
+        :type max_alternatives: int
+        :param max_alternatives: (Optional) Maximum number of recognition
+                                 hypotheses to be returned. The server may
+                                 return fewer than maxAlternatives.
+                                 Valid values are 0-30. A value of 0 or 1
+                                 will return a maximum of 1. Defaults to 1
+
+        :type profanity_filter: bool
+        :param profanity_filter: If True, the server will attempt to filter
+                                 out profanities, replacing all but the
+                                 initial character in each filtered word with
+                                 asterisks, e.g. ``'f***'``. If False or
+                                 omitted, profanities won't be filtered out.
+
+        :type speech_context: list
+        :param speech_context: A list of strings (max 50) containing words and
+                               phrases "hints" so that the speech recognition
+                               is more likely to recognize them. This can be
+                               used to improve the accuracy for specific words
+                               and phrases. This can also be used to add new
+                               words to the vocabulary of the recognizer.
+
+        :rtype: :class:`~google.cloud.speech.operation.Operation`
+        :returns: Operation for asynchronous request to Google Speech API.
+        """
+        data = _build_request_data(sample, language_code, max_alternatives,
+                                   profanity_filter, speech_context)
+        api_response = self._connection.api_request(
+            method='POST', path='speech:asyncrecognize', data=data)
+
+        operation = Operation.from_dict(api_response, self._client)
+        operation.caller_metadata['request_type'] = 'AsyncRecognize'
+        return operation
+
+    def sync_recognize(self, sample, language_code=None, max_alternatives=None,
+                       profanity_filter=None, speech_context=None):
+        """Synchronous Speech Recognition.
+
+        .. _sync_recognize: https://cloud.google.com/speech/reference/\
+                            rest/v1beta1/speech/syncrecognize
+
+        See `sync_recognize`_.
+
+        :type sample: :class:`~google.cloud.speech.sample.Sample`
+        :param sample: Instance of ``Sample`` containing audio information.
+
+        :type language_code: str
+        :param language_code: (Optional) The language of the supplied audio as
+                              BCP-47 language tag. Example: ``'en-GB'``.
+                              If omitted, defaults to ``'en-US'``.
+
+        :type max_alternatives: int
+        :param max_alternatives: (Optional) Maximum number of recognition
+                                 hypotheses to be returned. The server may
+                                 return fewer than maxAlternatives.
+                                 Valid values are 0-30. A value of 0 or 1
+                                 will return a maximum of 1. Defaults to 1
+
+        :type profanity_filter: bool
+        :param profanity_filter: If True, the server will attempt to filter
+                                 out profanities, replacing all but the
+                                 initial character in each filtered word with
+                                 asterisks, e.g. ``'f***'``. If False or
+                                 omitted, profanities won't be filtered out.
+
+        :type speech_context: list
+        :param speech_context: A list of strings (max 50) containing words and
+                               phrases "hints" so that the speech recognition
+                               is more likely to recognize them. This can be
+                               used to improve the accuracy for specific words
+                               and phrases. This can also be used to add new
+                               words to the vocabulary of the recognizer.
+
+        :rtype: list
+        :returns: A list of dictionaries. One dict for each alternative. Each
+                  dictionary typically contains two keys (though not
+                  all will be present in all cases)
+
+                  * ``transcript``: The detected text from the audio recording.
+                  * ``confidence``: The confidence in language detection, float
+                    between 0 and 1.
+
+        :raises: ValueError if more than one result is returned or no results.
+        """
+        data = _build_request_data(sample, language_code, max_alternatives,
+                                   profanity_filter, speech_context)
+        api_response = self._connection.api_request(
+            method='POST', path='speech:syncrecognize', data=data)
+
+        if len(api_response['results']) > 0:
+            results = api_response['results']
+            return [Result.from_api_repr(result) for result in results]
+        else:
+            raise ValueError('No results were returned from the API')
+
+
+def _build_request_data(sample, language_code=None, max_alternatives=None,
+                        profanity_filter=None, speech_context=None):
+    """Builds the request data before making API request.
+
+    :type sample: :class:`~google.cloud.speech.sample.Sample`
+    :param sample: Instance of ``Sample`` containing audio information.
+
+    :type language_code: str
+    :param language_code: (Optional) The language of the supplied audio as
+                          BCP-47 language tag. Example: ``'en-GB'``.
+                          If omitted, defaults to ``'en-US'``.
+
+    :type max_alternatives: int
+    :param max_alternatives: (Optional) Maximum number of recognition
+                             hypotheses to be returned. The server may
+                             return fewer than maxAlternatives.
+                             Valid values are 0-30. A value of 0 or 1
+                             will return a maximum of 1. Defaults to 1
+
+    :type profanity_filter: bool
+    :param profanity_filter: If True, the server will attempt to filter
+                             out profanities, replacing all but the
+                             initial character in each filtered word with
+                             asterisks, e.g. ``'f***'``. If False or
+                             omitted, profanities won't be filtered out.
+
+    :type speech_context: list
+    :param speech_context: A list of strings (max 50) containing words and
+                           phrases "hints" so that the speech recognition
+                           is more likely to recognize them. This can be
+                           used to improve the accuracy for specific words
+                           and phrases. This can also be used to add new
+                           words to the vocabulary of the recognizer.
+
+    :rtype: dict
+    :returns: Dictionary with required data for Google Speech API.
+    """
+    if sample.content is not None:
+        audio = {'content':
+                 _bytes_to_unicode(b64encode(_to_bytes(sample.content)))}
+    else:
+        audio = {'uri': sample.source_uri}
+
+    config = {'encoding': sample.encoding,
+              'sampleRate': sample.sample_rate}
+
+    if language_code is not None:
+        config['languageCode'] = language_code
+    if max_alternatives is not None:
+        config['maxAlternatives'] = max_alternatives
+    if profanity_filter is not None:
+        config['profanityFilter'] = profanity_filter
+    if speech_context is not None:
+        config['speechContext'] = {'phrases': speech_context}
+
+    data = {
+        'audio': audio,
+        'config': config,
+    }
+
+    return data