Extend Google Sheets with Google Cloud Storage Data

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

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 Buckets 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 Cloud Storage OData services:

Connect to Google Cloud Storage

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

1. First, navigate to the Connections page.
2. Click Add Connection and then search for and select the Google Cloud Storage connection. 👁 Selecting a data source (SQLite is shown)
   
3. Enter the necessary authentication properties to connect to Google Cloud Storage.

   Authenticate with a User Account

   You can connect without setting any connection properties for your user credentials. After setting InitiateOAuth to GETANDREFRESH, you are ready to connect.

   When you connect, the Google Cloud Storage OAuth endpoint opens in your default browser. Log in and grant permissions, then the OAuth process completes

   Authenticate with a Service Account

   Service accounts have silent authentication, without user authentication in the browser. You can also use a service account to delegate enterprise-wide access scopes.

   You need to create an OAuth application in this flow. See the Help documentation for more information. After setting the following connection properties, you are ready to connect:

   • InitiateOAuth: Set this to GETANDREFRESH.
   • OAuthJWTCertType: Set this to "PFXFILE".
   • OAuthJWTCert: Set this to the path to the .p12 file you generated.
   • OAuthJWTCertPassword: Set this to the password of the .p12 file.
   • OAuthJWTCertSubject: Set this to "*" to pick the first certificate in the certificate store.
   • OAuthJWTIssuer: In the service accounts section, click Manage Service Accounts and set this field to the email address displayed in the service account Id field.
   • OAuthJWTSubject: Set this to your enterprise Id if your subject type is set to "enterprise" or your app user Id if your subject type is set to "user".
   • ProjectId: Set this to the Id of the project you want to connect to.

   The OAuth flow for a service account then completes.

   👁 Connecting to a datasource (SQLite is shown)
   
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 Cloud Storage 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. 👁 Configure a new 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: 👁 API Server user settings
   

Creating API Endpoints for Google Cloud Storage

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

1. First, navigate to the API page and then click Add Table . 👁 Add tables
   
2. Select the connection you wish to access and click Next. 👁 Select the connection (SQLite is shown)
   
3. With the connection selected, create endpoints by selecting each table and then clicking Confirm. 👁 Adding tables from the connection (SQLite is shown)
   

Gather the OData Url

Having configured a connection to Google Cloud Storage 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 Cloud Storage 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/Buckets?select=Id,Name,OwnerId,Name";
 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 buckets = JSON.parse(json).value;

 var cols = [["Id","Name","OwnerId","Name"]]; 
 sheet.getRange(1,1,1,4).setValues(cols);

 row=2;
 for(var i in buckets){
 for (var j in buckets[i]) {
 switch (j) {
 case "Id":
 a1.offset(row,0).setValue(account[i][j]);
 break;
 case "Name":
 a1.offset(row,1).setValue(account[i][j]);
 break;
 case "OwnerId":
 a1.offset(row,2).setValue(account[i][j]);
 break;
 case "Name":
 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.