fix: Update instrumentation process handling logic (#801)

lib/uiautomator2.js

@@ -6,7 +6,7 @@ import {
   TEST_APK_PATH as testApkPath,
   version as serverVersion
 } from 'appium-uiautomator2-server';
-import { util, logger, timing } from 'appium/support';
+import { util, timing } from 'appium/support';
 import B from 'bluebird';
 import axios from 'axios';
 
@@ -17,7 +17,6 @@ const SERVICES_LAUNCH_TIMEOUT = 30000;
 const SERVER_PACKAGE_ID = 'io.appium.uiautomator2.server';
 const SERVER_TEST_PACKAGE_ID = `${SERVER_PACKAGE_ID}.test`;
 const INSTRUMENTATION_TARGET = `${SERVER_TEST_PACKAGE_ID}/androidx.test.runner.AndroidJUnitRunner`;
-const instrumentationLogger = logger.getLogger('Instrumentation');
 
 class UIA2Proxy extends JWProxy {
   /** @type {boolean} */
@@ -50,6 +49,9 @@ class UiAutomator2Server {
   /** @type {boolean|undefined} */
   disableSuppressAccessibilityService;
 
+  /** @type {import('teen_process').SubProcess|null} */
+  instrumentationProcess;
+
   constructor (log, opts = {}) {
     for (let req of REQD_PARAMS) {
       if (!opts || !util.hasValue(opts[req])) {
@@ -72,6 +74,7 @@ class UiAutomator2Server {
     this.proxyReqRes = this.jwproxy.proxyReqRes.bind(this.jwproxy);
     this.proxyCommand = this.jwproxy.command.bind(this.jwproxy);
     this.jwproxy.didInstrumentationExit = false;
+    this.instrumentationProcess = null;
   }
 
   /**
@@ -255,6 +258,9 @@ class UiAutomator2Server {
     while (retries < maxRetries) {
       this.log.info(`Waiting up to ${timeout}ms for UiAutomator2 to be online...`);
       this.jwproxy.didInstrumentationExit = false;
+      try {
+        await this.stopInstrumentationProcess();
+      } catch (ign) {}
       await this.startInstrumentationProcess();
       if (!this.jwproxy.didInstrumentationExit) {
         try {
@@ -312,18 +318,30 @@ class UiAutomator2Server {
     // Disable Google analytics to prevent possible fatal exception
     cmd.push('-e', 'disableAnalytics', 'true');
     cmd.push(INSTRUMENTATION_TARGET);
-    const instrumentationProcess = this.adb.createSubProcess(['shell', ...cmd]);
-    instrumentationProcess.on('output', (stdout, stderr) => {
-      const output = _.trim(stdout || stderr);
-      if (output) {
-        instrumentationLogger.debug(output);
-      }
-    });
-    instrumentationProcess.on('exit', (code) => {
-      instrumentationLogger.debug(`The process has exited with code ${code}`);
+    this.instrumentationProcess = this.adb.createSubProcess(['shell', ...cmd]);
+    for (const streamName of ['stderr', 'stdout']) {
+      this.instrumentationProcess.on(`line-${streamName}`, (line) => this.log.debug(`[Instrumentation] ${line}`));
+    }
+    this.instrumentationProcess.once('exit', (code, signal) => {
+      this.log.debug(`[Instrumentation] The process has exited with code ${code}, signal ${signal}`);
       this.jwproxy.didInstrumentationExit = true;
     });
-    await instrumentationProcess.start(0);
+    await this.instrumentationProcess.start(0);
+  }
+
+  async stopInstrumentationProcess () {
+    if (!this.instrumentationProcess) {
+      return;
+    }
+
+    try {
+      if (this.instrumentationProcess.isRunning) {
+        await this.instrumentationProcess.stop();
+      }
+    } finally {
+      this.instrumentationProcess.removeAllListeners();
+      this.instrumentationProcess = null;
+    }
   }
 
   async deleteSession () {
@@ -336,6 +354,11 @@ class UiAutomator2Server {
       this.log.warn(`Did not get confirmation UiAutomator2 deleteSession worked; ` +
           `Error was: ${err}`);
     }
+    try {
+      await this.stopInstrumentationProcess();
+    } catch (err) {
+      this.log.warn(`Could not stop the instrumentation process. Original error: ${err.message}`);
+    }
   }
 
   async cleanupAutomationLeftovers (strictCleanup = false) {

package.json

@@ -56,7 +56,7 @@
     "singleQuote": true
   },
   "dependencies": {
-    "appium-adb": "^12.2.0",
+    "appium-adb": "^12.4.7",
     "appium-android-driver": "^9.7.0",
     "appium-chromedriver": "^5.6.28",
     "appium-uiautomator2-server": "^7.0.14",
@@ -68,7 +68,7 @@
     "lodash": "^4.17.4",
     "portscanner": "^2.2.0",
     "source-map-support": "^0.x",
-    "teen_process": "^2.0.0",
+    "teen_process": "^2.2.0",
     "type-fest": "^4.4.0"
   },
   "devDependencies": {