MSAL Logger Bug - Developer provided settings are overwritten by default config

[shahzaibj]

Developer provided logger settings for the logger MAY get overwritten by our default values in some cases. Consider the following scenario:

• A developer does NOT provide a logger config via config file such as: https://docs.microsoft.com/en-us/azure/active-directory/develop/msal-configuration#logging
• A developer however sets a log level on the logger using the following:
  • Logger.getInstance().setLogLevel(VERBOSE);
  • The developer calls this method prior to them even creating PublicClientApplication (as the Logger is static and not associated to PCA)
• At this point the log level is successfully set to VERBOSE
• Now the developer creates their PubliClientApplication.
• During PCA creation we internally try to read the MSAL config file and set Logger Settings from there. See this method.
• Since no developer provided config was passed, then we set the logger config based on the default config that ships with MSAL SDK located here: https://github.com/AzureAD/microsoft-authentication-library-for-android/blob/dev/msal/src/main/res/raw/msal_default_config.json
• The default config sets the value to WARN….and therefore we end up setting log level to WARN on the logger…and in the process overwriting the VERBOSE value that was previously set by the developer using the static method.

The issue happens because Logger is a Singleton class and so when the methods to set these logging settings are called prior to the creation of a PublicClientApplication then we run into such issue. In this case we are always going to overwrite these with what is supplied either in developer provided config or the default config.

[negoe]

Reopening after discussion with Shazaib.