java google-app-engine webrtc live-streaming apprtc

We cant start the AppRTC application using Google App Engine

Issue

I am trying to build and deploy apprtc application on my virtual machine(ubuntu 16.04). I have successfully deployed collider server. But I got an error when trying to start apprtc application using google app engine.

Steps followed

clone source code from https://github.com/webrtc/apprtc
start the collider server based on documentation(listen on port 8080)
going to apprtc directory and install node packages using command npm install.
successfully build apprtc application using command "grunt build".
install google app engine(appengine-java-sdk-1.9.62) from https://cloud.google.com/appengine/docs/standard/java/download

run apprtc application using following command:

DIRECTORY_PATH/appengine-java-sdk-1.9.62/bin/dev_appserver.sh out/app_engine/.

Got error like this

Executing [/usr/lib/jvm/java-8-oracle/jre/bin/java, -javaagent:/home/jishnu/manaf/appengine-java-sdk-1.9.62/lib/agent/appengine-agent.jar, -classpath, /home/jishnu/manaf/appengine-java-sdk-1.9.62/lib/appengine-tools-api.jar, com.google.appengine.tools.development.DevAppServerMain, --property=kickstart.user.dir=/home/jishnu/manaf/apprtc, /home/jishnu/manaf/apprtc/out/app_engine/.]
Feb 08, 2018 5:00:03 PM java.util.prefs.FileSystemPreferences$1 run
INFO: Created user preferences directory.
Feb 08, 2018 5:00:06 PM com.google.apphosting.utils.config.AppEngineWebXmlReader readAppEngineWebXml
SEVERE: Received exception processing /home/jishnu/manaf/apprtc/out/app_engine/WEB-INF/appengine-web.xml
com.google.apphosting.utils.config.AppEngineConfigException: Could not locate /home/jishnu/manaf/apprtc/out/app_engine/WEB-INF/appengine-web.xml
    at com.google.apphosting.utils.config.AppEngineWebXmlReader.getInputStream(AppEngineWebXmlReader.java:141)
    at com.google.apphosting.utils.config.AppEngineWebXmlReader.readAppEngineWebXml(AppEngineWebXmlReader.java:75)
    at com.google.apphosting.utils.config.EarHelper.readWebModule(EarHelper.java:178)
    at com.google.appengine.tools.development.ApplicationConfigurationManager$WarModuleConfigurationHandle.readConfiguration(ApplicationConfigurationManager.java:417)
    at com.google.appengine.tools.development.ApplicationConfigurationManager.<init>(ApplicationConfigurationManager.java:158)
    at com.google.appengine.tools.development.ApplicationConfigurationManager.newWarConfigurationManager(ApplicationConfigurationManager.java:100)
    at com.google.appengine.tools.development.ApplicationConfigurationManager.newWarConfigurationManager(ApplicationConfigurationManager.java:86)
    at com.google.appengine.tools.development.DevAppServerImpl.<init>(DevAppServerImpl.java:142)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at com.google.appengine.tools.development.DevAppServerFactory.doCreateDevAppServer(DevAppServerFactory.java:338)
    at com.google.appengine.tools.development.DevAppServerFactory.access$000(DevAppServerFactory.java:31)
    at com.google.appengine.tools.development.DevAppServerFactory$1.run(DevAppServerFactory.java:285)
    at com.google.appengine.tools.development.DevAppServerFactory$1.run(DevAppServerFactory.java:282)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.google.appengine.tools.development.DevAppServerFactory.createDevAppServer(DevAppServerFactory.java:281)
    at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:348)
    at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:45)
    at com.google.appengine.tools.development.DevAppServerMain.run(DevAppServerMain.java:223)
    at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:214)
Caused by: java.io.FileNotFoundException: /home/jishnu/manaf/apprtc/out/app_engine/WEB-INF/appengine-web.xml (No such file or directory)
    at java.io.FileInputStream.open0(Native Method)
    at java.io.FileInputStream.open(FileInputStream.java:195)
    at java.io.FileInputStream.<init>(FileInputStream.java:138)
    at java.io.FileInputStream.<init>(FileInputStream.java:93)
    at com.google.apphosting.utils.config.AppEngineWebXmlReader.getInputStream(AppEngineWebXmlReader.java:137)
    ... 21 more

com.google.apphosting.utils.config.AppEngineConfigException: Invalid configuration
    at com.google.appengine.tools.development.DevAppServerImpl.reportDeferredConfigurationException(DevAppServerImpl.java:435)
    at com.google.appengine.tools.development.DevAppServerImpl.doStart(DevAppServerImpl.java:232)
    at com.google.appengine.tools.development.DevAppServerImpl.access$000(DevAppServerImpl.java:47)
    at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:219)
    at com.google.appengine.tools.development.DevAppServerImpl$1.run(DevAppServerImpl.java:217)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerImpl.java:217)
    at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:368)
    at com.google.appengine.tools.util.Parser$ParseResult.applyArgs(Parser.java:45)
    at com.google.appengine.tools.development.DevAppServerMain.run(DevAppServerMain.java:223)
    at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMain.java:214)
Caused by: com.google.apphosting.utils.config.AppEngineConfigException: Invalid appengine-web.xml(/home/jishnu/manaf/apprtc/out/app_engine/WEB-INF/appengine-web.xml) - Could not locate /home/jishnu/manaf/apprtc/out/app_engine/WEB-INF/appengine-web.xml
    at com.google.apphosting.utils.config.EarHelper.readWebModule(EarHelper.java:180)
    at com.google.appengine.tools.development.ApplicationConfigurationManager$WarModuleConfigurationHandle.readConfiguration(ApplicationConfigurationManager.java:417)
    at com.google.appengine.tools.development.ApplicationConfigurationManager.<init>(ApplicationConfigurationManager.java:158)
    at com.google.appengine.tools.development.ApplicationConfigurationManager.newWarConfigurationManager(ApplicationConfigurationManager.java:100)
    at com.google.appengine.tools.development.ApplicationConfigurationManager.newWarConfigurationManager(ApplicationConfigurationManager.java:86)
    at com.google.appengine.tools.development.DevAppServerImpl.<init>(DevAppServerImpl.java:142)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at com.google.appengine.tools.development.DevAppServerFactory.doCreateDevAppServer(DevAppServerFactory.java:338)
    at com.google.appengine.tools.development.DevAppServerFactory.access$000(DevAppServerFactory.java:31)
    at com.google.appengine.tools.development.DevAppServerFactory$1.run(DevAppServerFactory.java:285)
    at com.google.appengine.tools.development.DevAppServerFactory$1.run(DevAppServerFactory.java:282)
    at java.security.AccessController.doPrivileged(Native Method)
    at com.google.appengine.tools.development.DevAppServerFactory.createDevAppServer(DevAppServerFactory.java:281)
    at com.google.appengine.tools.development.DevAppServerMain$StartAction.apply(DevAppServerMain.java:348)
    ... 3 more

Expected results

As per documentation, after this step, we should successfully access the apprtc application using http://localhost:443 url.

What is the actual issue with steps I followed?

Solution

com.google.apphosting.utils.config.AppEngineConfigException: Could not locate /home/jishnu/manaf/apprtc/out/app_engine/WEB-INF/appengine-web.xml

Well, from apprtc/src/app_engine/app.yaml it looks like the app is a python app, not a java one. There is no WEB-INF/appengine-web.xml for a python app.

So you need to:

install the python support in your gcloud SDK (if you didn't already) or use the GAE python SDK (see What is the relationship between Google's App Engine SDK and Cloud SDK?)

run the python development server, depending which SDK you use :

<gcloud_sdk>/bin/dev_appserver.py out/app_engine/.

<gae_python_sdk>/dev_appserver.py out/app_engine/.

This is more or less specified in the apprtc README.md at the source code page you referenced:

Running AppRTC locally requires Google App Engine SDK for Python,

...

Start the AppRTC dev server from the out/app_engine directory by running the Google App Engine SDK dev server,
<path to sdk>/dev_appserver.py ./out/app_engine