feat: Add default transform function for service bindings (#5195)

Author: tomfrenken

.changeset/neat-parents-search.md

@@ -0,0 +1,5 @@
+---
+'@sap-cloud-sdk/connectivity': minor
+---
+
+[New Functionality] Add transform function to create OAuth2ClientCredentials destinations from service bindings.

packages/connectivity/src/index.ts

@@ -59,7 +59,8 @@ export {
   ServiceBindingTransformOptions,
   transformServiceBindingToDestination,
   getAllDestinationsFromDestinationService,
-  getTenantId
+  getTenantId,
+  transformServiceBindingToClientCredentialsDestination
 } from './scp-cf';
 
 export type {

packages/connectivity/src/scp-cf/destination/service-binding-to-destination.spec.ts

@@ -1,7 +1,10 @@
 import { serviceToken } from '../token-accessor';
 import { resolveServiceBinding } from '../environment-accessor/service-bindings';
 import { decodeJwt } from '../jwt';
-import { transformServiceBindingToDestination } from './service-binding-to-destination';
+import {
+  transformServiceBindingToClientCredentialsDestination,
+  transformServiceBindingToDestination
+} from './service-binding-to-destination';
 
 const services = {
   destination: [
@@ -68,10 +71,10 @@ const services = {
       name: 'some-service1',
       label: 'some-service',
       tags: ['some-service'],
+      url: 'some-service-url',
       credentials: {
         clientid: 'some-service-clientid',
-        clientsecret: 'some-service-clientsecret',
-        uri: 'some-service-uri'
+        clientsecret: 'some-service-clientsecret'
       }
     }
   ],
@@ -211,4 +214,45 @@ describe('service binding to destination', () => {
       '"The provided service binding of type some-service is not supported out of the box for destination transformation."'
     );
   });
+
+  it('transforms a generic service binding to a client credentials destination', async () => {
+    const destination =
+      await transformServiceBindingToClientCredentialsDestination(
+        resolveServiceBinding('some-service')
+      );
+    expect(destination).toEqual(
+      expect.objectContaining({
+        url: 'some-service-url',
+        name: 'some-service1',
+        authentication: 'OAuth2ClientCredentials',
+        authTokens: expect.arrayContaining([
+          expect.objectContaining({
+            value: 'access-token',
+            type: 'bearer'
+          })
+        ])
+      })
+    );
+  });
+
+  it('transforms a generic service binding to a client credentials destination with custom url', async () => {
+    const destination =
+      await transformServiceBindingToClientCredentialsDestination(
+        resolveServiceBinding('some-service'),
+        { url: 'some-custom-service-url' }
+      );
+    expect(destination).toEqual(
+      expect.objectContaining({
+        url: 'some-custom-service-url',
+        name: 'some-service1',
+        authentication: 'OAuth2ClientCredentials',
+        authTokens: expect.arrayContaining([
+          expect.objectContaining({
+            value: 'access-token',
+            type: 'bearer'
+          })
+        ])
+      })
+    );
+  });
 });

packages/connectivity/src/scp-cf/destination/service-binding-to-destination.ts

@@ -56,6 +56,26 @@ export async function transformServiceBindingToDestination(
   );
 }
 
+/**
+ * Convenience function to create a destination from the provided service binding.
+ * Transforms a service binding to a destination of type OAuth2ClientCredentials.
+ * If a JWT is provided as part of the options, the tenant in the JWT is used for the client credentials grant, else the provider tenant is used, wherever applicable.
+ * @param service - The service binding to transform.
+ * @param options - Options used to transform the service binding.
+ * @returns A promise returning the transformed destination on success.
+ */
+export async function transformServiceBindingToClientCredentialsDestination(
+  service: Service,
+  options?: ServiceBindingTransformOptions & { url?: string }
+): Promise<Destination> {
+  const token = await serviceToken(service, options);
+  return buildClientCredentialsDestination(
+    token,
+    options?.url ?? service.url,
+    service.name
+  );
+}
+
 async function aicoreToDestination(
   service: Service,
   options?: ServiceBindingTransformOptions