cap-ui5-ts-utils

A collection of TypeScript utility functions for SAP UI5 and Fiori Elements development, designed to provide end-to-end type safety in interaction with OData services, common UI5 controls and CAP service calls.

Note: This package is designed to work with cds-typer as the basis for types. You can use your own types for cds services and entites if they match the signatures of those in cds-typer.

Features

• Action Invoker – Invoke actions with dynamically typed parameters in CAP services.
• Typed Event Parameters – Extract typed parameters from CDS functions.
• PickProperties – Pick properties of a base type, narrowing them if needed.

Installation

npm i cap-ui5-ts-utils

Usage

Import Utilities

import { genActionInvoker } from "cap-ui5-ts-utils";

genActionInvoker - Invoking a CAP Service Action

In a normal controller:

// MyController.controller.ts
import { genActionInvoker } from "cap-ui5-ts-utils";
import MyService from "#cds-models/MyService";

const invokeAction = genActionInvoker<MyService>();

async function myHandler(api: ExtensionAPI) {
  // Shows only actions available to `MyService`
  await invokeAction(api, "myServiceAction", {
    foo: "foo",
    bar: "bar",
  });
}

In an extended ObjectPage controller:

// MyObjectPage.controller.ts
import { genActionInvoker } from "cap-ui5-ts-utils";
import MyService from "#cds-models/MyService";

export default class MyObjectPage extends ControllerExtension<ExtensionAPI> {
  private invokeAction = genActionInvoker<MyService>();

  public onMyEvent(this: TicketStatus) {
    const extensionAPI = this.base.getExtensionAPI();

    this.invokeAction(extensionAPI, "myServiceAction", {
      foo: "foo",
      bar: "bar",
    }).then(() => {
      // Do more stuff
    });
  }
}

EventParams - Typed Event Parameters

// ./srv/myService.ts
import { EventParams } from "cap-ui5-ts-utils";
import { myFunction } from "#cds-models/MyService";

// Type check is done on the data obejct
const data: EventParams<typeof myFunction> = {
  foo: "foo",
  bar: "bar",
};

// ⚠️ No type check is done in .send()
await this.send(myFunction, data);

PickProperties - Pick and Narrow Properties

// Pick parameters and narrow them
type MyTypeParams = PickParams< MyType,
  "foo",         // Inherit from MyType
  "bar" | "baz", // Required but can be null
  "qux"          // Required and can't be null
>;
const myObject: MyTypeParams;

// Narrow properties and inherit all others
type MyOtherTypeParams = PickParams<
  MyOtherType,
  never,
  "bar"
> & MyOtherType;
const myOtherObject: MyOtherType;

License

ISC