Using Invoke Service in the Visual Rule Editor for forms based on Core Components

The Visual Rule Editor in an Adaptive Form supports the Invoke Service feature, which allows you to select a service from the list of Form Data Models (FDM) configured for your instance. You can map form fields directly to the input parameters of the service. To map form fields to the output parameters, use the event payload option for the specified Form Data Model service. Additionally, the Visual rule editor allows you to create rules for success and failure handlers for Invoke Service operations based on its output responses. Success handlers manage the successful execution of the Invoke Service operation, while failure handlers address any errors that occur.

Advantages of using the Invoke Service in the form’s rule editor

Here are few advantages of using Invoke Service operation in the rule editor of an Adaotive Form:

Invoke Service handlers for success and failure responses

Visual rule editor allows you to create rules for success and failure handlers for Invoke Service operations based on its output responses. Below image depicts the Invoke Service in Visual rule editor for an Adaptive Form:

To add success or failure handler, click Add Success Handler or Add Failure Handler, respectively.

When you click Add Success Handler, the Invoke Service Success Handler rule editor appears, allowing you to specify rules or logic to manage the Invoke Service output response when the operation is successful. You can specify rules even without defining conditions; however, you can add conditions for the success handler by clicking the Add Condition option.

You can add multiple rules to handle successful responses for the Invoke Service operation:

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Similarly, you can add rules to handle the Invoke Service output response when the operation is not successful. The image below displays the Invoke Service Failure Handler rule editor:

You can also add multiple rules to handle unsuccessful responses from the Invoke Service operation.

The Enable Error Validation on Server feature allows validations added by the author while designing an Adaptive Form to run on the server also.

Prerequisites for using the Invoke Service in the rule editor

Below are the prerequisites you must satisfy before using Invoke Service in the rule editor:

Exploring Invoke Service through different use cases

The Visual rule editor’s Invoke Service allows you to perform several useful operations. You can use it to populate dropdown options, set repeatable or simple panels, and validate form fields, all based on the output response of the Invoke Service. Thus, enhancing the flexibility and interactivity of your forms.

The table below describes a few scenarios in which the Invoke Service can be used:

Create a Get Information form that retrieves values based on the input entered in the Pet ID text box. The screenshot below shows the form used in these use cases:

Form Fields

Add the following fields to the form:

NOTE

In the Bind Reference field in the Properties dialog of the form fields, select and navigate to select the binary property you added in the Form Data Model (FDM).

Configuring panels

Set the panels as repetitive with the following constraints:

You can adjust the values of the repetitive panels to suit your requirements.

Data source

In this example, the Swagger Petstore API is used to configure a data source. The Form Data Model is configured for the getPetById service, which retrieves pet details based on the entered ID.

Let’s post the following JSON using the addPet service in the Swagger Petstore API:

{
        "id": 101,
        "category": {
            "id": 1,
            "name": "Labrador"
        },
        "name": "Lisa",
        "photoUrls": [
            "https://example.com/photos/lisa1.jpg",
            "https://example.com/photos/lisa2.jpg"
        ],
        "tags": [
            {
                "id": 1,
                "name": "vaccinated"
            },
            {
                "id": 2,
                "name": "friendly"
            },
            {
                "id": 3,
                "name": "house-trained"
            }
        ],
        "status": "available"
    }

Rules and logic are implemented using the Invoke Service action in the rule editor on the Pet ID textbox to demonstrate the mentioned use cases.

Let’s now explore the implementation of each use case in detail.

Use Case 1: Populate dropdown values using the output of Invoke Service

This use case demonstrates how to populate dropdown options dynamically based on the output of an Invoke Service.

Implementation

To achieve this, create a rule on the Pet ID text box to invoke the getPetById service. In the rule, set the enum property of the photo-url dropdown to photoUrls in Add Success Handler.

Output

Enter 101 in the Pet ID text box to dynamically populate the dropdown options based on the entered value.

Use Case 2: Set repeatable panel using output of Invoke Service

This use case demonstrates how to populate repeatable panels dynamically based on the output of an Invoke Service.

Considerations

Implementation

Create a rule on the Pet ID text box to invoke the getPetById service. In Add Success Handler, add another success handler response. Set the value of the tags panel to tags in the rule.

Output

Enter 101 in the Pet ID text box to populate the repeatable panel dynamically based on the input value.

Use Case 3: Set panel using output of Invoke Service

This use case demonstrates how to dynamically set the value of a panel based on the output of an Invoke Service.

Considerations

Implementation

Create a rule on the Pet ID text box to invoke the getPetById service. In Add Success Handler, add another success handler response. Set the value of the categoryname text box to category.name in the rule.

Output

Enter 101 in the Pet ID text box to populate the panel dynamically based on the input value.

Use Case 4: Use output parameter of Invoke Service to validate other fields

This use case demonstrates how to use the output of an Invoke Service to dynamically validate other form fields.

Implementation

Create a rule on the Pet ID text box to invoke the getPetById service. In Add Failure Handler, add a failure handler response. Hide the Submit button if an incorrect Pet ID is entered.

Output

Enter 102 in the Pet ID text box, and the Submit button is hidden.

Frequently asked questions

Q: What happens if I have created a rule using the Invoke Service and then upgrade to the latest version of the core components?

A: When you upgrade to the latest version of the core components, the Invoke Service rule automatically updates to the latest user interface, as it is backward compatible.

Q: Can I add multiple rules to handle successful or failure responses for the Invoke Service operation?

A: Yes, you can add multiple rules to handle successful or failure responses for the Invoke Service operation.

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