KB0030: Accessing the client-side error logs

Summary

Occasionally problems in Qualoupe require additional debugging information to be provided. At the server end of the system this information is logged to the Windows Event Log, but there is also some logging that takes place at the client end which may be useful when tracking down issues.

Note: Enabling the debugging tools described below can affect Qualoupe performance, and improper use can create further issues. You should only follow these steps when advised by a member of our support staff.

1: Open the Web Console

Firefox has a number of built-in tools for web developers. The main one needed for diagnosing Qualoupe issues is the Web Console. When opened, this appears at the bottom of the screen (by default), and can be configured to show messages from the application code and from the browser itself, as well as the details of data sent to and from the server.

The quickest, easiest way to open the console is to press CTRL-SHIFT-K on the keyboard (CMD-SHIFT-K on a Macintosh).

Alternatively you can access it via the Developer section of the Firefox main menu:

Firefox developer tools menu

After clicking the main menu button, then the “Developer” button, choose the “Web Console” entry.

Whichever approach you take, the web console should open, looking something like this:

Firefox web console

2: Configure the console

First of all, ensure that the “Console” tab is selected at the top left of the Web Console. Turn off all 5 classes of message by clicking the “Net”, “CSS”, “JS”, “Security” and “Logging” buttons until they are grey and there are no entries shown in the section below.

Which of these buttons needs to be re-enabled will depend on the type of problem that is being diagnosed. Only enable the ones that our support staff specify to avoid other types of message adding further confusion. Typically this will be “Net” and “Logging”, so these are covered in more detail below.

2.1: Using the “Net” option

If instructed to enable the “Net” button, you should also click on the drop-down menu and enable all four options that are listed:

Firefox web console Net menu

With the Net options enabled, the logging panel will show every call that is made to the server, whether it’s requesting a background image for the application, or sending a record to be stored in the database. In most cases these will all complete correctly, giving a status on the right-hand side that includes “200 OK”. Occasionally these calls will fail – typically showing “500 Internal Server Error” and coloured pink. These are the ones that usually warrant further investigation. In this screenshot we’ve deliberately induced an error to demonstrate the appearance:

Firefox web console Net with error

Clicking on one of these error entries will open another panel with more details about the request. Usually our support staff will require a copy of the text from the “Request Body” and “Response Body” sections – you should be able to copy the text to the clipboard by highlighting it and pressing CTRL-C (or COMMAND-C for Macintosh users). Then you can paste it directly into a bug report or email.

Firefox web console Net request details

2.2: Using the “Logging” option

The “Logging” class shows messages created by the Qualoupe developers and will often contain more details or clues about the source of problems – although mostly it’s just informative information about what the code is doing. If instructed to enable the “Logging” button, you should also click on the drop-down menu and enable all four options that are listed:

Firefox web console Logging menu

If you are instructed to send the log details to Two Fold Software, you can right-click in the main logging panel and choose “Select All”. Then copy the information to the clipboard to paste directly into a bug report or email.

2.3: Using other options

It’s rare that the “CSS”, “JS” or “Security” options provide any useful debugging information, but if you are instructed to enable these by our support staff, the instructions are similar to those for the “Logging” option above. In all cases you should enable both the “Errors” and “Warnings” options in the associated drop-down menu, but you shouldn’t need to enable “Reflows” in the CSS menu.

3: Producing useful bug reports

The web console can quickly fill with entries, most of which are not useful when debugging an issue. To provide the most useful information to our developers, please follow this approach:

1) Enable the relevant options, as instructed by our support staff.
2) Use Qualoupe to navigate to the point where the error occurs, but stop short of performing the action (save, load, lookup of data, etc) that triggers the problem.
3) Click on the “Clear” button in the web console.
4) Perform the action that triggers the issue.
5) Send the requested data to our support staff, or add it to the relevant issue in our bugtracker. (Usually this means the log entries and/or “Request/Response Body” for problem network requests, unless otherwise specified)

By clearing the console just before the problem occurs it’s easier for our support staff to see exactly what might be triggering the issue without it being obscured by lots of extra data.

4: Disable the Web Console

Once you have provided the information requested, you should close the Web Console by repeating the same steps you used to open it (i.e. press CTRL-SHIFT-K). You should not use Qualoupe with the Web Console open during normal operations as the additional debugging tools can impact performance, or even break parts of the application completely.

Conclusion

You shouldn’t generally need to use the Web Console, but for some issues it can provide a valuable insight into the state of the client end code that can make debugging much easier.

You should only enable the console under instruction from our support staff, and should disable it as soon as you are no longer actively using it to gather data.

markc

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