add initial changes to queries converting PromiseLike -> Promise

Author: stephenarosaj

packages/data-connect/src/api/query.ts

@@ -67,7 +67,7 @@ export interface QueryResult<Data, Variables>
  * Promise returned from `executeQuery`
  */
 export interface QueryPromise<Data, Variables>
-  extends PromiseLike<QueryResult<Data, Variables>> {
+  extends Promise<QueryResult<Data, Variables>> {
   // reserved for special actions like cancellation
 }
 

packages/data-connect/src/network/transport/index.ts

@@ -26,7 +26,7 @@ export interface DataConnectTransport {
   invokeQuery<T, U>(
     queryName: string,
     body?: U
-  ): PromiseLike<{ data: T; errors: Error[] }>;
+  ): Promise<{ data: T; errors: Error[] }>;
   invokeMutation<T, U>(
     queryName: string,
     body?: U
@@ -35,7 +35,12 @@ export interface DataConnectTransport {
   onTokenChanged: (token: string | null) => void;
 }
 
-export interface CancellableOperation<T> extends PromiseLike<{ data: T }> {
+// QUESTION:
+// is this the class we should be using instead of replacing "PromiseLike" with "Promise" ?
+//   - it adds "cancel" in there for us
+//   - it extends promise so it's not really a "frankenstein" promise - no need for Symbol.toStringTag
+//   - what about binding though?
+export interface CancellableOperation<T> extends Promise<{ data: T }> {
   cancel: () => void;
 }
 

packages/data-connect/src/network/transport/rest.ts

@@ -161,7 +161,7 @@ export class RESTTransport implements DataConnectTransport {
   invokeQuery: <T, U>(
     queryName: string,
     body?: U
-  ) => PromiseLike<{ data: T; errors: Error[] }> = <T, U = unknown>(
+  ) => Promise<{ data: T; errors: Error[] }> = <T, U = unknown>(
     queryName: string,
     body: U
   ) => {
@@ -183,9 +183,22 @@ export class RESTTransport implements DataConnectTransport {
       )
     );
 
+    // QUESTION:
+    // my understanding is that the code below does the following:
+    //   - return an object with properties which are methods (the same methods required for Promise, plus one more, "cancel")
+    //   - each of these methods should be bound to the corresponding method from the withAuth promise
+    //   - why not just return withAuth? is this so we can add the "cancel" method in there?
+    // ANOTHER QUESTION:
+    //   - do we want queries to be cancellable? there was no "cancel" method written here, i added it
     return {
       then: withAuth.then.bind(withAuth),
-      catch: withAuth.catch.bind(withAuth)
+      catch: withAuth.catch.bind(withAuth),
+      finally: withAuth.finally.bind(withAuth),
+      cancel: () => abortController.abort(),
+      get [Symbol.toStringTag]() {
+        return 'Promise';
+      }
+
     };
   };
   invokeMutation: <T, U>(
@@ -213,8 +226,8 @@ export class RESTTransport implements DataConnectTransport {
     });
 
 
-    // QUESTIONS:
-    // 1) my understanding is that the code below does the following:
+    // QUESTION:
+    // my understanding is that the code below does the following:
     //   - return an object with properties which are methods (the same methods required for Promise, plus one more, "cancel")
     //   - each of these methods should be bound to the corresponding method from the taskResult promise
     //   - why not just return taskResult? is this so we can add the "cancel" method in there?