Add generics to server add-on connection

Reviewed By: mweststrate

Differential Revision: D34307356

fbshipit-source-id: 27e61355a85995368ebb197c42d58f4145473567

desktop/flipper-common/src/ServerAddOn.tsx

@@ -48,13 +48,25 @@ export type FlipperPluginReceiverRes =
   | undefined
   | void;
 
-export type FlipperPluginReceiver = (
-  data: any,
+export type FlipperPluginReceiver<T> = (
+  data: T,
 ) => FlipperPluginReceiverRes | Promise<FlipperPluginReceiverRes>;
 
-export interface ServerAddOnPluginConnection {
-  send(method: string, params: unknown): void;
-  receive(method: string, receiver: FlipperPluginReceiver): void;
+export type EventsContract = Record<string, any>;
+export type MethodsContract = Record<string, (params: any) => Promise<any>>;
+
+export interface ServerAddOnPluginConnection<
+  Events extends EventsContract,
+  Methods extends MethodsContract,
+> {
+  send<T extends keyof Events & string>(
+    method: T,
+    ...params: Events[T] extends never ? [] : [Events[T]]
+  ): void;
+  receive<T extends keyof Methods & string>(
+    method: T,
+    receiver: FlipperPluginReceiver<Parameters<Methods[T]>[0]>,
+  ): void;
 }
 
 export interface FlipperServerForServerAddOn extends FlipperServer {
@@ -65,7 +77,10 @@ export interface FlipperServerForServerAddOn extends FlipperServer {
 }
 
 export type ServerAddOnCleanup = () => Promise<void>;
-export type ServerAddOn = (
-  connection: ServerAddOnPluginConnection,
+export type ServerAddOn<
+  Events extends EventsContract,
+  Methods extends MethodsContract,
+> = (
+  connection: ServerAddOnPluginConnection<Events, Methods>,
   {flipperServer}: {flipperServer: FlipperServerForServerAddOn},
 ) => Promise<ServerAddOnCleanup>;

desktop/flipper-common/src/index.tsx

@@ -47,6 +47,7 @@ export {
   getErrorFromErrorLike,
   deserializeRemoteError,
 } from './utils/errors';
+export {createControlledPromise} from './utils/controlledPromise';
 export * from './GK';
 export * from './clientUtils';
 export * from './settings';

desktop/flipper-common/src/utils/controlledPromise.tsx

@@ -0,0 +1,47 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+type Res<T> = {
+  promise: Promise<T>;
+  resolve: (...res: T extends void ? [] : [T]) => void;
+  reject: (reason: unknown) => void;
+} & (
+  | {
+      state: 'pending';
+      promiseVal: undefined;
+    }
+  | {state: 'resolved'; promiseVal: T}
+  | {state: 'rejected'; promiseVal: unknown}
+);
+
+export const createControlledPromise = <T,>(): Res<T> => {
+  let resolve!: Res<T>['resolve'];
+  let reject!: Res<T>['reject'];
+  let state: 'pending' | 'resolved' | 'rejected' = 'pending';
+  let promiseVal: T | unknown | undefined;
+  const promise = new Promise<T>((resolveP, rejectP) => {
+    resolve = ((val) => {
+      state = 'resolved';
+      promiseVal = val;
+      resolveP(val as T | PromiseLike<T>);
+    }) as typeof resolve;
+    reject = (err) => {
+      state = 'rejected';
+      promiseVal = err;
+      rejectP(err);
+    };
+  });
+  return {
+    promise,
+    resolve,
+    reject,
+    state,
+    promiseVal,
+  } as Res<T>;
+};

desktop/flipper-plugin/src/__tests__/api.node.tsx

@@ -52,6 +52,7 @@ test('Correct top level API exposed', () => {
       "Tracked",
       "TrackingScope",
       "batch",
+      "createControlledPromise",
       "createDataSource",
       "createState",
       "createTablePlugin",

desktop/flipper-plugin/src/index.tsx

@@ -146,6 +146,7 @@ export const TestUtils = TestUtilites;
 export {
   sleep,
   timeout,
+  createControlledPromise,
   DeviceOS,
   DeviceType,
   DeviceLogEntry,

desktop/flipper-plugin/src/plugin/DevicePlugin.tsx

@@ -8,12 +8,7 @@
  */
 
 import {SandyPluginDefinition} from './SandyPluginDefinition';
-import {
-  BasePluginInstance,
-  BasePluginClient,
-  EventsContract,
-  MethodsContract,
-} from './PluginBase';
+import {BasePluginInstance, BasePluginClient} from './PluginBase';
 import {FlipperLib} from './FlipperLib';
 import {Atom, ReadOnlyAtom} from '../state/atom';
 import {
@@ -22,6 +17,8 @@ import {
   DeviceLogEntry,
   CrashLog,
   ServerAddOnControls,
+  EventsContract,
+  MethodsContract,
 } from 'flipper-common';
 
 export type DeviceLogListener = (entry: DeviceLogEntry) => void;

desktop/flipper-plugin/src/plugin/Plugin.tsx

@@ -8,17 +8,16 @@
  */
 
 import {SandyPluginDefinition} from './SandyPluginDefinition';
-import {
-  BasePluginInstance,
-  BasePluginClient,
-  EventsContract,
-  MethodsContract,
-} from './PluginBase';
+import {BasePluginInstance, BasePluginClient} from './PluginBase';
 import {FlipperLib} from './FlipperLib';
 import {Device} from './DevicePlugin';
 import {batched} from '../state/batch';
 import {Atom, createState, ReadOnlyAtom} from '../state/atom';
-import {ServerAddOnControls} from 'flipper-common';
+import {
+  ServerAddOnControls,
+  EventsContract,
+  MethodsContract,
+} from 'flipper-common';
 
 type PreventIntersectionWith<Contract extends Record<string, any>> = {
   [Key in keyof Contract]?: never;

desktop/flipper-plugin/src/plugin/PluginBase.tsx

@@ -18,10 +18,11 @@ import {Idler} from '../utils/Idler';
 import {Notification} from './Notification';
 import {Logger} from '../utils/Logger';
 import {CreatePasteArgs, CreatePasteResult} from './Paste';
-import {ServerAddOnControls} from 'flipper-common';
-
-export type EventsContract = Record<string, any>;
-export type MethodsContract = Record<string, (params: any) => Promise<any>>;
+import {
+  EventsContract,
+  MethodsContract,
+  ServerAddOnControls,
+} from 'flipper-common';
 
 type StateExportHandler<T = any> = (
   idler: Idler,

desktop/flipper-server-core/src/plugins/ServerAddOnModuleToDesktopConnection.tsx

@@ -23,9 +23,9 @@ export type ServerAddOnModuleToDesktopConnectionEvents = {
 
 export class ServerAddOnModuleToDesktopConnection
   extends EventEmitter
-  implements ServerAddOnPluginConnection
+  implements ServerAddOnPluginConnection<any, any>
 {
-  private subscriptions: Map<string, FlipperPluginReceiver> = new Map();
+  private subscriptions: Map<string, FlipperPluginReceiver<any>> = new Map();
 
   constructor(private readonly pluginName: string) {
     super();
@@ -44,7 +44,7 @@ export class ServerAddOnModuleToDesktopConnection
     this.emit('message', message);
   }
 
-  receive(method: string, receiver: FlipperPluginReceiver) {
+  receive(method: string, receiver: FlipperPluginReceiver<any>) {
     this.subscriptions.set(method, receiver);
   }
 

desktop/flipper-server-core/src/plugins/__tests__/PluginManager.node.tsx

@@ -7,13 +7,12 @@
  * @format
  */
 
-import {ServerAddOnStartDetails} from 'flipper-common';
+import {ServerAddOnStartDetails, createControlledPromise} from 'flipper-common';
 import {loadServerAddOn} from '../loadServerAddOn';
 import {PluginManager} from '../PluginManager';
 import {ServerAddOnManager} from '../ServerAddManager';
 import {ServerAddOnModuleToDesktopConnection} from '../ServerAddOnModuleToDesktopConnection';
 import {
-  createControlledPromise,
   detailsBundled,
   detailsInstalled,
   initialOwner,

desktop/flipper-server-core/src/plugins/__tests__/ServerAddOn.node.tsx

@@ -7,12 +7,11 @@
  * @format
  */
 
-import {ServerAddOnStartDetails} from 'flipper-common';
+import {ServerAddOnStartDetails, createControlledPromise} from 'flipper-common';
 import {loadServerAddOn} from '../loadServerAddOn';
 import {ServerAddOn} from '../ServerAddOn';
 import {ServerAddOnModuleToDesktopConnection} from '../ServerAddOnModuleToDesktopConnection';
 import {
-  createControlledPromise,
   detailsBundled,
   detailsInstalled,
   initialOwner,

desktop/flipper-server-core/src/plugins/__tests__/utils.tsx

@@ -17,17 +17,3 @@ export const detailsBundled: ServerAddOnStartDetails = {
 export const detailsInstalled: ServerAddOnStartDetails = {
   path: '/dagobar/',
 };
-
-export const createControlledPromise = <T,>() => {
-  let resolve!: (...res: T extends void ? [] : [T]) => void;
-  let reject!: (reason: unknown) => void;
-  const promise = new Promise<T>((resolveP, rejectP) => {
-    resolve = resolveP as typeof resolve;
-    reject = rejectP;
-  });
-  return {
-    promise,
-    resolve,
-    reject,
-  };
-};

desktop/flipper-server-core/src/plugins/loadServerAddOn.tsx

@@ -17,7 +17,7 @@ import {assertNotNull} from '../comms/Utilities';
 import defaultPlugins from '../defaultPlugins';
 
 interface ServerAddOnModule {
-  default: ServerAddOnFn;
+  default: ServerAddOnFn<any, any>;
 }
 
 export const loadServerAddOn = (

docs/extending/flipper-plugin.mdx

@@ -1174,6 +1174,43 @@ Usage: `safeStringify(dataStructure)`
 
 Serialises the given data structure using `JSON.stringify`, but doesn't throw if the processes failed, but rather returns a `<unserializable ...>` string.
 
+### createControlledPromise
+
+Creates a promise and functions to resolve/reject it externally. Alsoprovides its current state.
+
+Returns:
+```ts
+// When the promise is pending
+type Res<T> = {
+  promise: Promise<T>;
+  resolve: (...res: T extends void ? [] : [T]) => void;
+  reject: (reason: unknown) => void;
+  state: 'pending';
+  promiseVal: undefined;
+} | {
+  promise: Promise<T>;
+  resolve: (...res: T extends void ? [] : [T]) => void;
+  reject: (reason: unknown) => void;
+  state: 'resolved';
+  // Resolved value
+  promiseVal: T;
+} | {
+  promise: Promise<T>;
+  resolve: (...res: T extends void ? [] : [T]) => void;
+  reject: (reason: unknown) => void;
+  state: 'rejected';
+  // Rejection reason
+  promiseVal: unknown;
+}
+```
+
+Usage:
+```js
+const controllerPromise = createControlledPromise()
+someService.on('event', (val) => controllerPromise.resolve(val))
+await controllerPromise.promise
+```
+
 ## TestUtils
 
 The object `TestUtils` as exposed from `flipper-plugin` exposes utilities to write unit tests for Sandy plugins.