This directory contains samples for Google Cloud Bigtable. Google Cloud Bigtable is Google's NoSQL Big Data database service. It's the same database that powers many core Google services, including Search, Analytics, Maps, and Gmail.

This sample demonstrates how to use Stackdriver Monitoring to scale Cloud Bigtable based on CPU usage.

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 metricscaler.py

usage: metricscaler.py [-h] [--high_cpu_threshold HIGH_CPU_THRESHOLD]
                       [--low_cpu_threshold LOW_CPU_THRESHOLD]
                       [--short_sleep SHORT_SLEEP] [--long_sleep LONG_SLEEP]
                       bigtable_instance bigtable_cluster

Scales Cloud Bigtable clusters based on CPU usage.

positional arguments:
  bigtable_instance     ID of the Cloud Bigtable instance to connect to.
  bigtable_cluster      ID of the Cloud Bigtable cluster to connect to.

optional arguments:
  -h, --help            show this help message and exit
  --high_cpu_threshold HIGH_CPU_THRESHOLD
                        If Cloud Bigtable CPU usage is above this threshold,
                        scale up
  --low_cpu_threshold LOW_CPU_THRESHOLD
                        If Cloud Bigtable CPU usage is below this threshold,
                        scale down
  --short_sleep SHORT_SLEEP
                        How long to sleep in seconds between checking metrics
                        after no scale operation
  --long_sleep LONG_SLEEP
                        How long to sleep in seconds between checking metrics
                        after a scaling operation

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.