[futurepress#95] Android: Add native methods to obtain the currently running service

Author: birdofpreyru

README.md

@@ -89,7 +89,9 @@ and [old][Old Architecture] RN architectures.
   - [extractBundledAssets()] — Extracts bundled assets into a regular folder
     (Android-specific).
   - [getActiveServer()] — Gets currently active, starting, or stopping
-    server instance, if any.
+    server instance, if any, according to the TS layer data.
+  - [getActiveServerId()] — Gets ID of the currently active, starting, or
+    stopping server instance, if any, according to the Native layer data.
   - [resolveAssetsPath()] — Resolves relative paths for bundled assets.
   - [ERROR_LOG_FILE] — Location of the error log file.
   - [STATES] — Enumerates possible states of [Server] instance.
@@ -551,6 +553,13 @@ within `options` argument:
   special `hostname` values to ask the library to automatically select
   appropriate non-local address._
 
+- `id` — **number** — Optional. Allows to enforce a specific ID,
+  used to communicate with the server instance within the Native layer, thus
+  it allows to re-connect to an existing native server instance.
+  See [getActiveServerId()] for details, and also pay attention to set
+  the correct `state` option value in this case. By default is is assigned
+  by the library.
+
 - `nonLocal` — **boolean** — Optional. By default, if `hostname`
   option was not provided, the server starts at the "`127.0.0.1`" (loopback)
   address, and it is only accessible within the host app.
@@ -565,6 +574,11 @@ within `options` argument:
 - `port` — **number** — Optional. The port at which to start the server.
   If 0 (default) an available port will be automatically selected.
 
+- `state` — [STATES] — Optional. Allows to enforce initial
+  server state value, which is needed when connecting to an existing
+  native server instance with help of the `id` option.
+  By default it is set to `STATES.INACTIVE`.
+
 - `stopInBackground` — **boolean** — Optional.
 
   By default, the server continues to work as usual when its host app enters
@@ -795,17 +809,43 @@ This is an Android-specific function; it does nothing on other platforms.
 
 ### getActiveServer()
 [getActiveServer()]: #getactiveserver
-```js
+```ts
 import {getActiveServer} from '@dr.pogodin/react-native-static-server';
 
-getActiveServer(): Server;
+getActiveServer(): Server | undefined;
 ```
 Returns currently active, starting, or stopping [Server] instance, if any exist
 in the app. It does not return, however, any inactive server instance which has
 been stopped automatically because of `stopInBackground` option, when the app
 entered background, and might be automatically started in future if the app
 enters foreground again prior to an explicit [.stop()] call for that instance.
 
+**NOTE:** The result of this function is based on the TypeScript layer data
+(that's why it is synchronous), in contrast to the [getActiveServerId()]
+function below, which calls into the Native layer, and returns ID of the active
+server based on that.
+
+### getActiveServerId()
+[getActiveServerId()]: #getactiveserverid
+```ts
+import {getActiveServerId} from '@dr.pogodin/react-native-static-server';
+
+getActiveServerId(): Promise<number | null>;
+```
+Returns ID of the currently active, starting, or stopping server instance,
+if any exist in the Native layer.
+
+This function is provided in response to
+[the ticket #95](https://github.com/birdofpreyru/react-native-static-server/issues/95),
+which asked to provide a way to re-connect to a server running within the Native
+layer after a reset of TypeScript RN layer. The ID returned by this function can
+be passed in into [Server] instance [constructor()] to create server instance
+communicating to the existing native layer server.
+
+**NOTE:** It is different from [getActiveServer()] function above, which
+returns the acurrently active, starting, or stopping [Server] instance based on
+TypeScript layer data.
+
 ### resolveAssetsPath()
 [resolveAssetsPath()]: #resolveassetspath
 ```ts

android/src/main/java/com/drpogodin/reactnativestaticserver/ReactNativeStaticServerModule.kt

@@ -34,6 +34,11 @@ class ReactNativeStaticServerModule internal constructor(context: ReactApplicati
         return constants
     }
 
+    @ReactMethod
+    override fun getActiveServerId(promise: Promise) {
+      promise.resolve(server?.id)
+    }
+
     @ReactMethod
     override fun getLocalIpAddress(promise: Promise) {
         try {
@@ -90,10 +95,8 @@ class ReactNativeStaticServerModule internal constructor(context: ReactApplicati
         pendingPromise = promise
         val emitter: DeviceEventManagerModule.RCTDeviceEventEmitter = getReactApplicationContext()
                 .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter::class.java)
-        server = Server(
-                configPath,
-                errlogPath
-        ) { signal, details ->
+
+        server = Server(id, configPath, errlogPath) { signal, details ->
             if (signal !== Server.LAUNCHED) server = null
             if (pendingPromise == null) {
                 val event = Arguments.createMap()

android/src/main/java/com/lighttpd/Server.kt

@@ -22,6 +22,7 @@ import java.util.function.BiConsumer
  * if any, has terminated or crashed before launching a new one!
  */
 class Server(
+        var id: Double,
         var configPath: String,
         var errlogPath: String,
         private val signalConsumer: BiConsumer<String, String?>

android/src/oldarch/ReactNativeStaticServerSpec.kt

@@ -6,19 +6,24 @@ import com.facebook.react.bridge.ReactContextBaseJavaModule
 
 abstract class ReactNativeStaticServerSpec internal constructor(context: ReactApplicationContext) :
   ReactContextBaseJavaModule(context) {
-    abstract override fun getName(): String
-    abstract fun getTypedExportedConstants(): Map<String, Any>
+  abstract override fun getName(): String
+  abstract fun getTypedExportedConstants(): Map<String, Any>
 
-    override fun getConstants(): Map<String, Any>? {
-        return getTypedExportedConstants()
-    }
+  abstract fun getActiveServerId(promise: Promise)
 
-    abstract fun start(
-            id: Double, configPath: String?, errlogPath: String?, promise: Promise?)
+  override fun getConstants(): Map<String, Any>? {
+      return getTypedExportedConstants()
+  }
 
-    abstract fun getLocalIpAddress(promise: Promise)
-    abstract fun getOpenPort(address: String, promise: Promise)
-    abstract fun stop(promise: Promise?)
+  abstract fun start(
+    id: Double,
+    configPath: String,
+    errlogPath: String,
+    promise: Promise)
+
+  abstract fun getLocalIpAddress(promise: Promise)
+  abstract fun getOpenPort(address: String, promise: Promise)
+  abstract fun stop(promise: Promise?)
 
   abstract fun addListener(eventName: String?)
 

src/NativeReactNativeStaticServer.ts

@@ -11,6 +11,8 @@ export interface Spec extends TurboModule {
 
   addListener(eventName: string): void;
 
+  getActiveServerId(): Promise<number | null>;
+
   removeListeners(count: number): void;
 
   start(id: number, configPath: string, errlogPath: string): Promise<string>;

src/ReactNativeStaticServer.ts

@@ -1,5 +1,7 @@
 import { NativeModules, Platform } from 'react-native';
 
+import type { Spec } from './NativeReactNativeStaticServer';
+
 const LINKING_ERROR =
   `The package '@dr.pogodin/react-native-static-server' doesn't seem to be linked. Make sure: \n\n` +
   Platform.select({ ios: "- You have run 'pod install'\n", default: '' }) +
@@ -24,4 +26,4 @@ const ReactNativeStaticServer = ReactNativeStaticServerModule
       },
     );
 
-export default ReactNativeStaticServer;
+export default ReactNativeStaticServer as Spec;

src/index.tsx

@@ -93,21 +93,15 @@ class StaticServer {
   _stopInBackground: boolean;
   _port: number;
 
-  _state: STATES = STATES.INACTIVE;
+  _state: STATES;
   _stateChangeEmitter = new Emitter<[STATES, string, Error | undefined]>();
 
   // TODO: It will be better to use UUID, but I believe "uuid" library
   // I would use won't work in RN without additional workarounds applied
   // to RN setup to get around some issues with randombytes support in
   // RN JS engine. Anyway, it should be double-checked later, but using
   // timestamps as ID will do for now.
-
-  // NOTE: For some reasons RN-Windows corrupts large numbers sent
-  // as event arguments across JS / Native boundary.
-  // Everything smaller than 65535 seems to work fine, so let's just
-  // truncate these IDs for now.
-  // See: https://github.com/microsoft/react-native-windows/issues/11322
-  _id = Date.now() % 65535;
+  _id: number;
 
   // It is used to serialize state change requests, thus ensuring that parallel
   // requests to start / stop the server won't result in a corrupt state.
@@ -166,9 +160,17 @@ class StaticServer {
     fileDir,
     hostname,
 
+    // NOTE: For some reasons RN-Windows corrupts large numbers sent
+    // as event arguments across JS / Native boundary.
+    // Everything smaller than 65535 seems to work fine, so let's just
+    // truncate these IDs for now.
+    // See: https://github.com/microsoft/react-native-windows/issues/11322
+    id = Date.now() % 65535,
+
     /* DEPRECATED */ nonLocal = false,
 
     port = 0,
+    state = STATES.INACTIVE,
     stopInBackground = false,
 
     /* DEPRECATED */ webdav,
@@ -177,22 +179,26 @@ class StaticServer {
     errorLog?: boolean | ErrorLogOptions;
     fileDir: string;
     hostname?: string;
+    id?: number;
 
     /* DEPRECATED */ nonLocal?: boolean;
 
     port?: number;
+    state?: STATES;
     stopInBackground?: boolean;
 
     /* DEPRECATED */ webdav?: string[];
   }) {
     if (errorLog) this._errorLog = errorLog === true ? {} : errorLog;
 
     this._extraConfig = extraConfig;
+    this._id = id;
 
     this._nonLocal = nonLocal;
     this._hostname = hostname || (nonLocal ? '' : LOOPBACK_ADDRESS);
 
     this._port = port;
+    this._state = state;
     this._stopInBackground = stopInBackground;
 
     if (!fileDir) throw Error('`fileDir` MUST BE a non-empty string');
@@ -422,3 +428,5 @@ export function getActiveServer() {
       server.state !== STATES.INACTIVE && server.state !== STATES.CRASHED,
   );
 }
+
+export const getActiveServerId = ReactNativeStaticServer.getActiveServerId;