Consume Google Cloud Storage OData Feeds in SAP Lumira

You can use the CData API Server to create data visualizations based on Google Cloud Storage data in SAP Lumira. The API Server enables connectivity to live data: dashboards and reports can be refreshed on demand. This article shows how to create a chart that is always up to date.

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 SAP Lumira, 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.
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.

   
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.
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 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 .
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 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:

Connect to Google Cloud Storage from SAP Lumira

Follow the steps below to retrieve Google Cloud Storage data into SAP Lumira. You can execute an SQL query or use the UI.

1. In SAP Lumira, click File -> New -> Query with SQL. The Add New Dataset dialog is displayed.
2. Expand the Generic section and click the Generic OData 2.0 Connector option.
3. In the Service Root URI box, enter the OData endpoint of the API Server. This URL will resemble the following:

   https://your-server:8080/api.rsc
   

4. In the User Name and Password boxes, enter the username and authtoken of an API user. These credentials will be used in HTTP Basic authentication.

5. Select entities in the tree or enter an SQL query. This article imports Google Cloud Storage Buckets entities.

   

6. When you click Connect, SAP Lumira will generate the corresponding OData request and load the results into memory. You can then use any of the data processing tools available in SAP Lumira, such as filters, aggregates, and summary functions.

   

Create Data Visualizations

After you have imported the data, you can create data visualizations in the Visualize room. Follow the steps below to create a basic chart.

1. In the Measures and Dimensions pane, drag measures and dimensions onto the x-axis and y-axis fields in the Visualization Tools pane. SAP Lumira automatically detects dimensions and measures from the metadata service of the API Server.

   By default, the SUM function is applied to all measures. Click the gear icon next to a measure to change the default summary.

2. In the Visualization Tools pane, select the chart type.
3. In the Chart Canvas pane, apply filters, sort by measures, add rankings, and update the chart with the current Google Cloud Storage data.