Extend Google Sheets with Google Data Catalog Data

Interact with Google Data Catalog data from Google Sheets through macros, custom functions, and add-ons. The CData API Server enables connectivity to Google Data Catalog data from cloud-based and mobile applications like Google Sheets. The API Server is a lightweight Web application that produces OData services for Google Data Catalog.

Google Apps Script can consume these OData services in the JSON format. This article shows how to create a simple add-on that populates a Google Spreadsheet with Schemas data.

Set Up the API Server

If you have not already done so, download the CData API Server. Once you have installed the API Server, follow the steps below to begin producing secure Google Data Catalog OData services:

Connect to Google Data Catalog

To work with Google Data Catalog data from Google Sheets, we start by creating and configuring a Google Data Catalog connection. Follow the steps below to configure the API Server to connect to Google Data Catalog data:

1. First, navigate to the Connections page.
2. Click Add Connection and then search for and select the Google Data Catalog connection.
3. Enter the necessary authentication properties to connect to Google Data Catalog.

   Google Data Catalog uses the OAuth authentication standard. Authorize access to Google APIs on behalf on individual users or on behalf of users in a domain.

   Before connecting, specify the following to identify the organization and project you would like to connect to:

   • OrganizationId: The ID associated with the Google Cloud Platform organization resource you would like to connect to. Find this by navigating to the cloud console.

     Click the project selection drop-down, and select your organization from the list. Then, click More -> Settings. The organization ID is displayed on this page.

   • ProjectId: The ID associated with the Google Cloud Platform project resource you would like to connect to.

     Find this by navigating to the cloud console dashboard and selecting your project from the Select from drop-down. The project ID will be present in the Project info card.

   When you connect, the OAuth endpoint opens in your default browser. Log in and grant permissions to the application to completes the OAuth process. For more information, refer to the OAuth section in the Help documentation.

   
4. After configuring the connection, click Save & Test to confirm a successful connection.

Configure API Server Users

Next, create a user to access your Google Data Catalog data through the API Server. You can add and configure users on the Users page. Follow the steps below to configure and create a user:

1. On the Users page, click Add User to open the Add User dialog.
2. Next, set the Role, Username, and Privileges properties and then click Add User.
3. An Authtoken is then generated for the user. You can find the Authtoken and other information for each user on the Users page:

Creating API Endpoints for Google Data Catalog

Having created a user, you are ready to create API endpoints for the Google Data Catalog tables:

1. First, navigate to the API page and then click Add Table .
2. Select the connection you wish to access and click Next.
3. With the connection selected, create endpoints by selecting each table and then clicking Confirm.

Gather the OData Url

Having configured a connection to Google Data Catalog data, created a user, and added resources to the API Server, you now have an easily accessible REST API based on the OData protocol for those resources. From the API page in API Server, you can view and copy the API Endpoints for the API:

Retrieve Google Data Catalog Data

Open the Script Editor from your spreadsheet by clicking Tools -> Script Editor. In the Script Editor, add the following function to populate a spreadsheet with the results of an OData query:

function retrieve(){
  var url = "https://MyUrl/api.rsc/Schemas?select=Id,Type,DatasetName,ProjectId";
  var response = UrlFetchApp.fetch(url,{
    headers: {"Authorization": "Basic " + Utilities.base64Encode("MyUser:MyAuthtoken")}
  }); 
  var json = response.getContentText();
  var sheet = SpreadsheetApp.getActiveSheet();
  var a1 = sheet.getRange('a1');
  var index=1;
  var schemas = JSON.parse(json).value;

  var cols = [["Id","Type","DatasetName","ProjectId"]]; 
  sheet.getRange(1,1,1,4).setValues(cols);

  row=2;
  for(var i in schemas){
    for (var j in schemas[i]) {
      switch (j) {
        case "Id":
          a1.offset(row,0).setValue(account[i][j]);
          break;
        case "Type":
          a1.offset(row,1).setValue(account[i][j]);
          break;
        case "DatasetName":
          a1.offset(row,2).setValue(account[i][j]);
          break;
        case "ProjectId":
          a1.offset(row,3).setValue(account[i][j]);
          break;
      }      
    }
    row++;
  }
}

Follow the steps below to add an installable trigger to populate the spreadsheet when opened:

1. Click Resources -> Current Project's Triggers -> Add a New Trigger.
2. Select retrieve in the Run menu.
3. Select From Spreadsheet.
4. Select On open.

After closing the dialog, you are prompted to allow access to the application.

You can test the script by clicking Publish -> Test as Add-On. Select the version, installation type, and spreadsheet to create a test configuration. You can then select and run the test configuration.