Google Authentication Puppet Module

Module Description

This module provides the types to authenticate with Google Cloud Platform.

When executing operations on Google Cloud Platform, e.g. creating a virtual machine, a SQL database, etc., you need to be authenticated to be able to carry on with the request.

All Google Cloud Platform modules use an unified authentication mechanism, provided by this module.

Setup

To install this module on your Puppet Master (or Puppet Client/Agent), use the Puppet module installer:

puppet module install google-gauth

Note: Google Cloud Platform modules that require authentication will automatically install this module, as it will be listed in their dependencies.

Required gem (libraries)

The authentication module depends on gems released by Google. Puppet does not install gems automatically as part of installing modules. To install, run:

/opt/puppetlabs/puppet/bin/gem install googleauth google-api-client

As everything related to system configuration, you can install the gem using Puppet itself ;-)...

package { [
    'googleauth',
    'google-api-client',
  ]:
    ensure   => present,
    provider => puppet_gem,
}

Usage

gauth_credential { 'mycred':
  path     => $cred_path, # e.g. '/home/nelsonjr/my_account.json'
  provider => serviceaccount,
  scopes   => [
    'https://www.googleapis.com/auth/ndev.clouddns.readwrite',
  ],
}

About Service Accounts

This module uses service accounts to authenticate with Google Cloud Platform. Google Cloud Platform project administrators manage service accounts. They can create, modify and delete accounts and grant account specific privileges on the projects. Those privileges will be used by Puppet to carry on the operations on behalf of the user.

Getting a Service Account key

This module uses the JSON version of the service account key file. When in the IAM & Admin section of the Developer Console the administrator can retrieve a key file. Select the JSON as the key format.

The file you download is the one provided in the path property.

Reference

Parameters

gauth_credential

provider

• serviceaccount [preferred] This is the preferred method of specifying credentials, because it does not rely on any pre-existing system configuration that Puppet can't track. You'll need a credential file, but you can easily manage that with a file { } resource.

• defaultuseraccount If you have gcloud setup you can piggyback on the account currently set as active for the user running Puppet.

  Warning! Please be aware that the account is subject to whichever account is set as active on gcloud tool, so the results will not be always consistent if they change under Puppet by the user.

scopes

The scopes your authentication request will be limited to. When executing actions against Google Cloud Platform you should choose the minimum amount of privileges to carry on the operations to avoid accidentally affecting other resources. For example if I want to manage virtual machines you should request only "Compute R/W". That way you don't accidentally modify your DNS records.

Google's Puppet modules for Google Cloud Platform list the scopes you can use in their Puppet Forge documentation page. You can alternatively look at Google Cloud Platform documentation for the product you're interacting with.

A few examples:

path

If you specify the serviceaccount provider this property points to an absolute path of the service account file (in JSON format).

Functions

gauth_credential_serviceaccount_for_function

Creates the credential token required by other client-side functions to retrieve Google Cloud Platform resource properties, e.g. Compute Instance IP address.

This function uses a service account JSON file to provide credentials. A service account can be created an managed using Google Cloud IAM service.

It is common to require dynamic data to be fetched and used by depedent resources, for example to lock down a database to a specific machines you require the machine's IP address. However the IP address is dynamic and cannot be determined upfront, so we need to provide the means to retrieve it programmatically. To allow such access GCP requires credentials. This function builds such credentials.

Arguments

• path: the path for the service account credential JSON file

• scopes: an array of scopes to allow access to. The service account privileges will be constrained to the list provided in this parameter.

Examples

$fn_auth = gauth_credential_serviceaccount_for_function(
  '/root/my_account.json', ['https://www.googleapis.com/auth/sqlservice.admin']
)