rest

Cloud Bigtable Python REST Examples

This example shows how to use the HBase REST server with Cloud Bigtable. This involves two steps:

1. Installing and configuring an HBase client to serve as the REST gateway.
2. Installing and configuring a REST client.

In this example, we use a Python REST client built with the requests library. This client is not an extensive, all-purpose application, but rather a simple demonstration of some common operations.

HBase REST gateway setup and configuration

1. Install the Cloud Bigtable HBase shell on a Compute Engine VM. Be sure to install HBase 1.1.1 or later. Earlier versions are not compatible with this example.

2. Start the REST gateway. Run the following command to start HBase's REST API server in the background, suppressing all log output:

    bin/hbase rest start > /dev/null 2>&1 &
   

   If you prefer, you can redirect HBase's log output to a file:

    bin/hbase rest start > hbase-log.txt 2>&1 &
   

3. If you would like to connect to your REST gateway using your external IP, open a firewall port:

    gcloud compute firewall-rules create <instance_name> --allow=tcp:8080
   

   Warning: Opening a firewall port creates a security risk. To connect from a different VM instance without opening a firewall port, use the VM instance's private internal IP instead of the external IP. You can find the internal IP in the Developers Console by going to Compute Engine > VM Instances and clicking on your instance.

REST client setup and configuration

1. In put_get.py and put_get_with_client.py, change baseurl to match the IP address of the REST server.

2. Use pip to install the virtualenv module which creates a virtual Python environment:

    sudo pip install virtualenv
   

3. Create an environment called rest_env, and activate the environment:

    virtualenv rest_env
    source rest_env/bin/activate
   

4. Install the REST API client's dependencies in the virtual environment:

    pip install -r requirements.txt
   

Instructions

• put_get.py demonstrates some simple operations directly using requests.

• put_get_with_client.py uses rest_client.py to wrap some of the details in methods, as well as creating the table new-table5001 if it doesn't exist. The test script does not delete the table after it finishes running. You can use the HBase shell to delete the table.

• Running the test scripts

  python put_get.py or python put_get_with_client.py

  Both commands should print "Done!" if all the operations succeed.

• Stopping the REST server

  Once you're done using the test scripts, run the following command to stop HBase's REST API server:

    kill $(pgrep hbase)
  

Troubleshooting Notes

OS X

If you run into a problem relating a java.net.UnknownHostException when using localhost as the server on OS X, try explicitly setting an entry in the the /etc/hosts file as described.