[FEATURE]: Add File-Based Logging Functionality

[mhellmeier]

Is your feature request related to a problem?

Yes

Description

Sometimes, the application doesn't work anymore and only shows the default error message. In a live scenario, it is really hard to debug the problem, because error messages are only printed on the JavaScript console.

Describe the solution you'd like

It would be great to add a file-based logging system because it enables post-failure analysis. Like a file called photobooth.log in the root directory containing information about the past. This can be easily integrated into the photoboothTools:
https://github.com/andi34/photobooth/blob/dev/src/js/tools.js#L6

Describe alternatives you've considered

Additional context

A simple writeFile based function is totally enough. But there are also some 3rd party dependencies that might be interesting like winston. Further, it has to be considered that the file must be protected against external access because it contains sensitive data.

Additional nice-to-have logging features are:

• Logs shown in the web interface
• Possibility to delete all logs manually over the web interface
• Possibility to configure different log levels
• Different logging configurations (like one log file for every day etc.)

[andi34]

Hey! Sounds good, but currently I don't have much time to look at this.

Issues from PHP are logged already via https://github.com/andi34/photobooth/blob/dev/lib/log.php

The log is accessible via the Debugpanel, the logs get read here: https://github.com/andi34/photobooth/blob/dev/api/serverInfo.php

Currently there's more or less 3 log level:

1. default
2. via dev mode
3. via advanced logging
   7e740c4

The dev mode got independent from the example images eaa6e9d

Do you have time to look at the js logging parts and can open a PR?

[mhellmeier]

Yeah, a JS version from the PHP logging would be great.

Currently, I am also not able to implement it. If I get some time in the near future and if the feature isn't solved until then, I can implement it.