webapp-container needs some help

Actually, it does, if invoked with "-h" or "--help":

$ webapp-container --help
Usage: webapp-container [-h|--help] [--fullscreen] [--maximized] [--inspector] [--app-id=APP_ID] [--homepage=URL] [--webapp=name] [--name=NAME] [--icon=PATH] [--webappModelSearchPath=PATH] [--webappUrlPatterns=URL_PATTERNS] [--accountProvider=PROVIDER_NAME] [--accountSwitcher] [--enable-back-forward] [--enable-addressbar] [--store-session-cookies] [--user-agent-string=USER_AGENT] [URL]
Options:
  -h, --help display this help message and exit
  --fullscreen display full screen
[…]

yes, i know; that was just to make it a bit more friendly on first
encounter ;)

On Fri, Dec 11, 2015 at 11:33 AM, Olivier Tilloy <
<email address hidden>> wrote:

> Actually, it does, if invoked with "-h" or "--help":
>
> $ webapp-container --help
> Usage: webapp-container [-h|--help] [--fullscreen] [--maximized]
> [--inspector] [--app-id=APP_ID] [--homepage=URL] [--webapp=name]
> [--name=NAME] [--icon=PATH] [--webappModelSearchPath=PATH]
> [--webappUrlPatterns=URL_PATTERNS] [--accountProvider=PROVIDER_NAME]
> [--accountSwitcher] [--enable-back-forward] [--enable-addressbar]
> [--store-session-cookies] [--user-agent-string=USER_AGENT] [URL]
> Options:
> -h, --help display this help message and exit
> --fullscreen display full screen
> […]
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1525147
>
> Title:
> webapp-container needs some help
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/webapps-sprint/+bug/1525147/+subscriptions
>

Currently, it's not possible to show `--help` neither in the Terminal app nor in an SSH session connected to the phone.

   $ webapp-container --help
   Loading module: 'libubuntu_application_api_touch_mirclient.so.3.0.0'
   UbuntuClientIntegration: connection to Mir server failed. Check that a Mir server is
   running, and the correct socket is being used and is accessible. The shell may have
   rejected the incoming connection, so check its log file
   Aborted (core dumped)

Looks like the webapp-container binary requires a successful connection to the Mir server. This should not be required, I believe.

The call to `printUsage()` happens in `BrowserApplication::initialize()`, which is after the constructor has been called. The base class `QApplication` seems to require a Mir server (or X server) running.

Conclusion
----------

- In order to be able to print the usage on the console without requiring a Mir server this call needs to be made before the constructor is called.

- It may also be a good idea to check all the command line arguments and reject invalid ones. (Is there no module available for this, similar to Python's argparse? Can we use QCommandLineParser? http://doc.qt.io/qt-5/qcommandlineparser.html)

References
----------

- http://bazaar.launchpad.net/~ubuntu-branches/ubuntu/wily/webbrowser-app/wily/view/head:/src/app/browserapplication.cpp#L121
- http://bazaar.launchpad.net/~ubuntu-branches/ubuntu/wily/webbrowser-app/wily/view/head:/src/app/browserapplication.cpp#L42
- http://doc.qt.io/qt-5/qcommandlineparser.html