hop-user-manual/modules/ROOT/pages/technology/google/google-info.adoc

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:documentationPath: /technology/google/
:language: en_US

= Google Technology

== Introduction

The Google technology stack is supported in Hop through a number of plugins.  We briefly touch upon them below.

=== Google Analytics

You can use the `Google Analytics` transform to get information from this service.

== Google Sheets

It can be very convenient to save data into a Google sheet or indeed to read from it.  You can do this using the `Google Sheets Input` and `Google Sheets Output` transforms.

== Google Drive

Hop has a Virtual File System (VFS) plugin for Google Drive.  You need to generate a credentials file to make it work.  Follow the Google documentation to see how that is done.  You also need to specify a folder in which security tokens are going to be saved.  You can specify both in the Hop system configuration options.  This can be done in the Hop GUI: go to the "Google Drive" tab in the Options dialog (from the Tools menu).  You can also use the `hop-conf` script with the following options:

[source,shell script]
----
      -gdc, --google-drive-credentials-file=<credentialsFile>
                            Configure the path to a Google Drive credentials JSON
                              file
      -gdt, --google-drive-tokens-folder=<tokensFolder>
                            Configure the path to a Google Drive tokens folder
----

Once done you will see a `googleDrive` entry in the central `hop-config.json` file:

[source,json]
----
{
  "googleDrive" : {
    "credentialsFile" : "/path/to/google-drive-credentials.json",
    "tokensFolder" : "/path/to/tokens"
  }
}
----

When you try to run the first time you'll see a message on the console where you executed Hop GUI or Hop Run saying something like:

[source]
----
Please open the following address in your browser:
  https://accounts.google.com/o/oauth2/auth?access_type=offline&client_id=yourClientId&redirect_uri=http://localhost:8888/Callback&response_type=code&scope=https://www.googleapis.com/auth/drive
----

Open that URL in a browser and authenticate the given client ID. You'll then get a token in the configured `tokens folder` with which you can work.

== Google Cloud Storage

Hop has a Virtual File System (VFS) plugin for Google Cloud Storage.

You need to generate a key file for a service account to make it work.  Go to the Google Cloud console to do this. Once you have a key file for your service account, with permissions to access your GCP storage, point to it with either a system environment variable called `GOOGLE_APPLICATION_CREDENTIALS` (standard Google way of doing this) or in the Options dialog in the 'Google Cloud' tab. You can also use `hop-conf`:

[source,shell script]
----
      -gck, --google-cloud-service-account-key-file=<serviceAccountKeyFile>
                            Configure the path to a Google Cloud service account JSON key file
----

Once done you will see a `googleCloud` entry in the central `hop-config.json` file:

[source,json]
----
{
  "googleCloud" : {
    "serviceAccountKeyFile" : "/path/to/your/google-key.json"
  }
}
----