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Azure Functions aka Az functions

Notes

  • Azure functions getting migrated to isolated worker model. Do not use in-process anymore.
  • Isolated worker model uses a default logging filter to only log warnings and higher log-levels via ILogger. This filter can be disabled (see: Azure function - Start-up and configuration
  • Logging config can be done in host.json for the functions host process or in application.json for the worker process.
  • Timer based trigger uses NCrontab expressions (instead of normal cron expression) which uses 6 instead of 5 values (including seconds). This site can help defining cron timers: https://ncrontab.swimburger.net
  • Local Az function testing / running
    • Ensure that local.settings.json exists (this does usually not get checked in by default) (see below).
    • An azure storage is needed. Simplest solution is to use Docker for it. Otherwise an emulator will do. See: https://learn.microsoft.com/en-us/azure/storage/common/storage-use-azurite
    • RunOnStartup - use this to immediately trigger the function. This can also be placed in a "Debug only" block (see below).
{ //  example: local.settings.json
    "IsEncrypted": false,
    "Values": {
        "AzureWebJobsStorage": "UseDevelopmentStorage=true",
        "FUNCTIONS_WORKER_RUNTIME": "dotnet-isolated"
}  

// example for RunOnStartup only in debug
public async Task Run(
    [TimerTrigger("0 15/30 9-20 * 5-9 *"
#if DEBUG
    , RunOnStartup=true
#endif
    )] TimerInfo myTimer)