This directory contains samples for Google Cloud Natural Language Tutorial. The `Google Cloud Natural Language API`_ provides natural language understanding technologies to developers, including sentiment analysis, entity recognition, and syntax analysis. This API is part of the larger Cloud Machine Learning API.

Authentication is typically done through Application Default Credentials, which means you do not have to change the code to authenticate as long as your environment has credentials. You have a few options for setting up authentication:

1. When running locally, use the Google Cloud SDK

   gcloud auth application-default login

2. When running on App Engine or Compute Engine, credentials are already set-up. However, you may need to configure your Compute Engine instance with additional scopes.

3. You can create a Service Account key file. This file can be used to authenticate to Google Cloud Platform services from any environment. To use the file, set the GOOGLE_APPLICATION_CREDENTIALS environment variable to the path to the key file, for example:

   export GOOGLE_APPLICATION_CREDENTIALS=/path/to/service_account.json

1. Install pip and virtualenv if you do not already have them.

2. Create a virtualenv. Samples are compatible with Python 2.7 and 3.4+.

   $ virtualenv env
   $ source env/bin/activate

3. Install the dependencies needed to run the samples.

   $ pip install -r requirements.txt

To run this sample:

$ python tutorial.py

usage: tutorial.py [-h] movie_review_filename

positional arguments:
  movie_review_filename
                        The filename of the movie review you'd like to
                        analyze.

optional arguments:
  -h, --help            show this help message and exit