#13173 WinAppDriver does not wait long startup an UWP app

add create session timeout and waitForCondition to retry the session creation in case of an err
add 'createSessionTimeout' capability for WindowsDriver only

README.md

@@ -26,6 +26,13 @@ let driver = new WindowsDriver();
 await driver.createSession(defaultCaps);
 ```
 
+## WindowsDriver-specific capabilities
+
+|Capability|Description|Values|
+|----------|-----------|------|
+|`createSessionTimeout`|Timeout in milliseconds used to retry `WinAppDriver` session startup. This capability could be used as a workaround for the long startup times of UWP applications (aka `Failed to locate opened application window with appId: TestCompany.my_app4!App, and processId: 8480`). Default value `20000`|e.g., `15000`|
+
+
 ## Watch code for changes, re-transpile and run unit tests:
 
 ```

lib/desired-caps.js

@@ -17,6 +17,9 @@ const desiredCapConstraints = {
     // recognize the cap,
     // but validate in the driver#validateDesiredCaps method
   },
+  createSessionTimeout: {
+    isNumber: true
+  },
   calendarFormat: {
     isString: true
   },

lib/winappdriver.js

@@ -3,17 +3,18 @@ import { JWProxy } from 'appium-base-driver';
 import log from './logger';
 import { SubProcess } from 'teen_process';
 import { WAD_INSTALL_PATH, verifyWAD } from './installer';
-import { retryInterval } from 'asyncbox';
+import { retryInterval, waitForCondition } from 'asyncbox';
 import cp from 'child_process';
 import B from 'bluebird';
 
 const REQUIRED_PARAMS = []; // XXYD 1-5-2018: removed app from required params because you can alternatively use appTopLevelWindow
 const DEFAULT_WAD_HOST = '127.0.0.1';
-const DEFAULT_WAD_PORT = 4724; //  should be non-4723 to avoid conflict on the same box
+const DEFAULT_WAD_PORT = 4724; // should be non-4723 to avoid conflict on the same box;
+const DEFAULT_CREATE_SESSION_TIMEOUT_MS = 20000; // retry start session creation during the timeout in milliseconds
 
 class WinAppDriver extends events.EventEmitter {
   constructor (opts = {}) {
-    const {host, port} = opts;
+    const {host, port, createSessionTimeout} = opts;
     super();
 
     for (let req of REQUIRED_PARAMS) {
@@ -25,6 +26,7 @@ class WinAppDriver extends events.EventEmitter {
 
     this.proxyHost = host || DEFAULT_WAD_HOST;
     this.proxyPort = port || DEFAULT_WAD_PORT;
+    this.createSessionTimeout = createSessionTimeout || DEFAULT_CREATE_SESSION_TIMEOUT_MS;
     this.proc = null;
     this.state = WinAppDriver.STATE_STOPPED;
     this.jwproxy = new JWProxy({server: this.proxyHost, port: this.proxyPort});
@@ -74,15 +76,15 @@ class WinAppDriver extends events.EventEmitter {
           this.changeState(WinAppDriver.STATE_STOPPED);
         }
       });
-      log.info(`Spawning winappdriver with: ${args.join(' ')}`);
+      log.info(`Spawning WinAppDriver with: ${args.join(' ')}`);
 
       // start subproc and wait for startDetector
       await this.proc.start(startDetector);
       await this.waitForOnline();
 
     } catch (e) {
       this.emit(WinAppDriver.EVENT_ERROR, e);
-      // just because we had an error doesn't mean the winappdriver process
+      // just because we had an error doesn't mean the WinAppDriver process
       // finished; we should clean up if necessary
       if (processIsAlive) {
         await this.proc.stop();
@@ -130,8 +132,41 @@ class WinAppDriver extends events.EventEmitter {
   }
 
   async startSession (caps) {
+
+    let createSessionTimeout = this.createSessionTimeout;
+    if (caps.createSessionTimeout) {
+      createSessionTimeout = Number.isInteger(caps.createSessionTimeout) ? caps.createSessionTimeout : parseInt(caps.createSessionTimeout, 10);
+    }
+
+    log.info(`Start WinAppDriver session during createSessionTimeout = '${createSessionTimeout}' ms.`);
     this.proxyReqRes = this.jwproxy.proxyReqRes.bind(this.jwproxy);
-    await this.jwproxy.command('/session', 'POST', {desiredCapabilities: caps});
+    let retryIteration = 0;
+    let lastError = null;
+
+    const condFn = async () => {
+      try {
+        retryIteration++;
+        await this.jwproxy.command('/session', 'POST', {desiredCapabilities: caps});
+        return true;
+      } catch (error) {
+        lastError = error;
+        log.warn(`Could not start WinAppDriver session error = '${error}', attempt = '${retryIteration}' from '${this.createSessionRetry}'`);
+        return false;
+      }
+    };
+
+    try {
+      await waitForCondition(condFn, {
+        waitMs: createSessionTimeout,
+        intervalMs: 500
+      });
+    } catch (timeoutError) {
+      log.debug(timeoutError);
+      if (lastError) {
+        throw (lastError);
+      }
+      throw (timeoutError);
+    }
   }
 
   async stop (emitStates = true) {
@@ -202,5 +237,5 @@ WinAppDriver.STATE_STARTING = 'starting';
 WinAppDriver.STATE_ONLINE = 'online';
 WinAppDriver.STATE_STOPPING = 'stopping';
 
-export { WinAppDriver, DEFAULT_WAD_HOST, DEFAULT_WAD_PORT};
+export { WinAppDriver, DEFAULT_WAD_HOST, DEFAULT_WAD_PORT };
 export default WinAppDriver;

package.json

@@ -54,7 +54,7 @@
     "watch": "gulp watch",
     "coverage": "gulp coveralls",
     "precommit-msg": "echo 'Pre-commit checks...' && exit 0",
-    "precommit-test": "REPORTER=dot gulp once",
+    "precommit-test": "env REPORTER=dot bash -c 'gulp once'",
     "lint": "gulp lint",
     "lint:fix": "gulp lint --fix",
     "install": "node install-npm.js"