feat: Add Promise-based callServiceAsync wrapper for async/await support (#1169)

Author: ikwilnaarhuisman

packages/roslib/src/core/Service.ts

@@ -96,6 +96,29 @@ export default class Service<
       timeout: timeout,
     });
   }
+
+  /**
+   * Wrapper of callService that returns a modern Promise-based interface for use with async/await.
+   * @see callService
+   * @param request - The service request to send.
+   * @param [timeout] - Optional timeout, in seconds, for the service call. A non-positive value means no timeout.
+   *                             If not provided, the rosbridge server will use its default value.
+   */
+  callServiceAsync(request: TRequest, timeout?: number): Promise<TResponse> {
+    return new Promise<TResponse>((resolve, reject) => {
+      this.callService(
+        request,
+        (res) => {
+          resolve(res);
+        },
+        (err) => {
+          reject(new Error(err));
+        },
+        timeout,
+      );
+    });
+  }
+
   /**
    * Advertise the service. This turns the Service object from a client
    * into a server. The callback will be called with every request

packages/roslib/test/service.test.ts

@@ -203,4 +203,31 @@ describe("Service", () => {
     await server.unadvertise();
     expect(server.isAdvertised).toBe(false);
   });
+
+  it("Successfully call a service with an asynchronous return", async () => {
+    const server = new Service<
+      undefined,
+      { success: boolean; message: string }
+    >({
+      ros,
+      serviceType: "std_srvs/Trigger",
+      name: "/test_service",
+    });
+    await server.advertise((_request, response) => {
+      response.success = true;
+      response.message = "bar";
+      return true;
+    });
+    const client = new Service({
+      ros,
+      serviceType: "std_srvs/Trigger",
+      name: "/test_service",
+    });
+    const response = await client.callServiceAsync({});
+
+    expect(response).toEqual({
+      success: true,
+      message: "bar",
+    });
+  }, 10_000);
 });