This directory contains samples for Google Cloud Natural Language API. The Google Cloud Natural Language API provides natural language understanding technologies to developers.

This tutorial demostrates how to use the classify_text method to classify content category of text files, and use the result to compare texts by their similarity to each other. See the tutorial page for details about this sample.

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 classify_text_tutorial.py

usage: classify_text_tutorial.py [-h]
                                 {classify,index,query,query-category} ...

Using the classify_text method to cluster texts.

positional arguments:
  {classify,index,query,query-category}
    classify            Classify the input text into categories.
    index               Classify each text file in a directory and write the
                        results to the index_file.
    query               Find the indexed files that are the most similar to
                        the query text.
    query-category      Find the indexed files that are the most similar to
                        the query label. The list of all available labels:
                        https://cloud.google.com/natural-
                        language/docs/categories

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

This sample uses the Google Cloud Client Library for Python. You can read the documentation for more details on API usage and use GitHub to browse the source and report issues.