Logging plays an important part in determining bugs in our code. It provides context for the developers about where and when errors occur.
- Most of the logs are saved under
%LOCALAPPDATA%/Microsoft/PowerToys. - For low-privilege processes (like preview handlers) the logs are saved under
%USERPROFILE%/AppData/LocalLow/Microsoft/PowerToys.
Logs are normally in a subfolder with the module name as title.
The BugReportTool will take logs from both locations when executed.
In C++ projects we use the awesome spdlog library for logging as a git submodule under the deps directory. To use it in your project, just include spdlog.props in a .vcxproj like this:
<Import Project="..\..\..\deps\spdlog.props" />It'll add the required include dirs and link the library binary itself.
For C# projects there is a static logger class in Managed Common called Logger.
To use it, add a project reference to ManagedCommon and add the following line of code to all the files using the logger:
using ManagedCommon;In the Main function (or a function with a similar meaning (like App in a App.xaml.cs file)) you have to call InitializeLogger and specify the location where the logs will be saved (always use a path scheme similar to this example):
Logger.InitializeLogger("\\FancyZones\\Editor\\Logs");For a low-privilege process you have to set the optional second parameter to true:
Logger.InitializeLogger("\\FileExplorer\\Monaco\\Logs", true);The Logger class contains the following logging functions:
// Logs an error that the utility encountered
Logger.LogError(string message);
Logger.LogError(string message, Exception ex);
// Logs an error that isn't that grave
Logger.LogWarning(string message);
// Logs what the app is doing at the moment
Logger.LogInfo(string message);
// Like LogInfo just with infos important for debugging
Logger.LogDebug(string message);
// Logs the current state of the utility.
Logger.LogTrace();