6 - Trigger Process from Your App

To connect Build Apps to Process Automation a destination needs to be created for the Build Process Automation from the SAP BTP Cockpit.

1. Go to your SAP BTP cockpit, enter your trial subaccount, and on the left select Instances and Subscriptions.

2. Under Instances, find your instance of the SAP Build Process Automation service.

   

   On the right, click the three dots, and then select Create Service Key.

   

3. Enter the name for service key as spa-key and choose Create.

   

   The service key is created and you can view the credentials by clicking View.

   

   When viewing the service key, make note of the following, which you’ll need for the destination.

   • api
   • clientid
   • clientsecret
   • url

   These values are needed next for the Destination Configuration.

   

4. Download the destination definition.

   Click sap_process_automation_service_user_access to go to the GitHub download page for the destination template, and then click the download button in the GitHub menu.

   

5. In the SAP BTP cockpit, click Connectivity > Destinations.

   

   Click Import Destination, and then select the sap_process_automation_service_user_access file you downloaded.

   

   The draft destination will be filled in except for the credentials and URLs.

   

6. Enter values for the following fields, based on the service key information you saved earlier.

   Destination Field	Value from Service Key
   Client ID	clientid
   Client Secret	clientsecret
   Token Service URL	url + /oauth/token

   The skeleton destination you imported assumes you are using US10 region and setting the URL field accordingly. Double-check the URL field in the destination, which should be the same as the api field in your service key.

   Select Use default client trust store.

   Click Save.

If you click Check Connection, you will get a 401 response code. This is OK and you have successfully created the destination

In order to trigger a process from SAP Build Apps, you must first publish the process – which makes the process discoverable from an SAP Build Apps project.

1. Open the SAP Build lobby.

   Click an empty space in the row of your project (do not open the project).

   

   The side panel should open.

2. Click Versions.

   

3. Click the 3 dots next to the latest version of your project (1.0.1) – notice the first version is Editable and the other versions are shown with the most recent one first.

   Click Publish to Library.

   

   A confirmation dialog is displayed. Click Publish.

   Published to Library should now appear next to the latest version of you project.

   

The process is published, but we need to reference it in our SAP Build Apps project.

1. In your SAP Build Apps project, go to the Integrations tab.

2. Click Add Integration

   

   Select Library.

   

   You should now see the process you published.

   

3. Select the process.

   On the left you will see actions available for this process, and he relevant inputs and outputs. For Trigger process, the inputs correspond to the inputs you created inside the process.

   

   Click Enable Process.

   Click Save.

Now that you enabled the process, let’s set up the logic to trigger it.

1. Click User Interface.

   Go to the Cart page.

2. Click on the Purchase button.

   Open the button’s logic canvas.

   

3. From the Core tab on the left, drag a Trigger process flow function onto the canvas, and connect it to the Component Tap event.

   The process should automatically have your process selected for the Process field.

   

4. You now need to bind all the fields that the process needs.

   Under Input Parameters, click Custom object, and set the following:

   

   Field	Binding
   Total:	Set to the following formula: SUM(MAP(data.OrderItems1,item.price * item.quantity))
   Order ID:	Set to Date and Variables > App variable > orderID
   Order Items:	Set to the following formula: MAP(data.OrderItems1, {product: item.product, price: item.price, quantity: NUMBER(item.quantity), total: item.price * item.quantity})

   You use a formula because you have to modify the data slightly before sending. Specifically, the quantity from the input box component is a string and you need to convert it to a number.

   Leave businessPartner: empty for now.

   Click Save.

5. Add Update record (for updating the CAP service) and Alert flow functions, as follows:

   

6. Configure the Update record, which is called to change the status of the order and set its total field, as follows:

   • Resource name: Set to Orders.

   • ID: Set to Date and Variables > App variable > orderID

     

   • Record: Click Custom object and set the fields as follows:

     

     • status: Set to Static text with value REQUESTED

     • total: Set to the following formula:

       JavaScript Copy

       SUM(MAP(data.OrderItems1,item.price * item.quantity))

     Click Save.

7. Configure the Alert by setting the Dialog title to Output value of another node > Trigger process > Error > message.

   Click Save.

   

8. Click Save (upper right).

In the same logic for the button, you want to:

• Alert the user that the purchase was successful
• Reset the cart ID (since it cannot be used anymore)
• Reset the items in your data variable.
• Go back to the home page

Update the logic as follows.

1. In the same logic for the button, add these additional flow functions and connect them as shown:

   

2. Configure the Alert by setting the Dialog title to static text:

   Text Copy

   Order requested. Returning to Home Page.

3. Configure the Set app variable as follows:

   • Variable name to orderID.

   • Leave the Assigned value blank.

4. Configure the Open page as follows:

   • Page to Home page.

5. Click Save (upper right).

There is no need to do anything for the Set data variable, since the data variable is automatically set to OrderItems since it is the only data variable for this page. And since you want to blank it out, the Record collection can be left as set to nothing.

1. Run your app again (click Preview to get started).

2. In the navigation bar on the left, click Cart.

   You should already have something in your cart. If not, go back to the home page and add something to your cart.

   No need to select a business partner.

3. Click Purchase.

   If all goes well, you should get a confirmation box.

   

   If you navigate to the Cart page, you’ll see there is nothing in your cart (and if you are really sharp, you’ll notice that the UUID for your cart has changed).

4. Now go back to the Monitoring tab and you should see that your app started an instance of your process.

   And if it is over 1000 for the total, it will set off the approval form. You will see your order ID in the title.

   

   Pretty cool, no?

   Now go to your inbox, and you see a new approval form, this time with your orderID in the title, and you will see that the script task was run.

   

   In the form itself, you’ll see the order ID and the order items. You’ll also see the total number of items, derived from the Script Task in your process.

   

   Click Approve (the form should disappear), and then refresh the list of tasks. Now you should see the approval notification, with the same order ID.

   

• Trigger Processes from SAP Build Apps #1 (video with free project)

Things to Ponder

We created a destination to SAP Build Process Automation using the authentication type OAuth2JWTBearer. What if we had used a simple OAuthClientCredentials type?

What are all the flow functions related to processes inside SAP Build Apps?

What does the MAP function do (that you used for calculating the total)? Why should you be careful when using this function?

What scenarios can you imagine where you’d want to create an app that would trigger a process?