Observe fire-and-forget startup tasks in WebHosting - #493
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_webApplication.StartAsync and StartupCache were started without being awaited or observed, so a startup failure of the web host or the cache initialization stayed silent. Both tasks are now tracked and any fault is logged through the application logger.
Read the AggregateException into a local before the null-conditional logger call so it is always observed, and log GetBaseException instead of the wrapping AggregateException. Drop the redundant Logging using directive already supplied by the Web SDK, document the new logger field, and move the helper methods into the existing Private methods region.
applicationData.Logger stays null unless OpenTelemetry logging is configured, which silently swallowed the newly observed startup faults in the default setup. The logger now falls back to the web application's own ILoggerFactory once the host is built. A faulting StartAsync also resets IsRunning so a host that failed to bind no longer reports itself as running.
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Summary
_webApplication.StartAsync(_cts.Token)andStartupCache(_cts.Token)inWebHosting.StartWebHostingwere started without being awaited or otherwise observed. The trailing.ConfigureAwait(false)onStartupCachehad no effect since the task was never awaited, so a startup failure of the web host or the cache initialization stayed completely silent.Both tasks are now tracked and observed through a new
ObserveStartupTaskhelper, which attaches a fault-only continuation that logs the exception via the application logger, without changing the fire-and-forget startup flow.Linked issues
Closes #195
Review notes
StartWebHostingremains synchronous by design (it is called from the non-asyncStartReceiving), so the fix keeps the startup calls fire-and-forget but ensures faults are logged rather than swallowed.