public async Task <HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken = default)
{
var itemDictionary = new Dictionary <string, object>();
HealthCheckResult retval;
try
{
foreach (var trigger in _timerTriggers)
{
if (trigger.IsTimerDisabled)
{
itemDictionary.Add(trigger.TimerTriggerFriendlyName, new TimerTriggerHealthResult {
LastCompletionTime = DateTime.MinValue, LastExpectedCompletionTime = DateTime.MinValue, IsTimerDisabled = true
});
}
else
{
//get last execution completion time
var blobPath = TimerHealthCheckHelper.GetBlobPath(trigger.TimerFullTypeName, _helperOptions);
var lastTimeString = await _blobStorage.DownloadFileAsTextAsync(blobPath).ConfigureAwait(false);
TimerHealthCheckStatus status = JsonSerializer.Deserialize <TimerHealthCheckStatus>(lastTimeString);
var lastExpectedTime = GetLastScheduledOccurrence(trigger.ScheduleExpression, _dateTimeService.CurrentDateTimeOffset.DateTime);
itemDictionary.Add(trigger.TimerTriggerFriendlyName, new TimerTriggerHealthResult {
LastCompletionTime = status.LastCheckpoint, LastExpectedCompletionTime = new DateTimeOffset(lastExpectedTime, status.LastCheckpoint.Offset)
});
}
}
var badTimers = itemDictionary.Where(x => !((TimerTriggerHealthResult)x.Value).IsTimerDisabled && ((((TimerTriggerHealthResult)x.Value).LastCompletionTime) < ((TimerTriggerHealthResult)x.Value).LastExpectedCompletionTime) && _dateTimeService.CurrentDateTimeOffset > ((TimerTriggerHealthResult)x.Value).LastExpectedCompletionTime + _options.ToleranceTimeSpan).Select(x => new { TimerName = x.Key, Result = x.Value as TimerTriggerHealthResult }).ToList();
if (badTimers.Any())
{
var sb = new StringBuilder();
foreach (var item in badTimers)
{
sb.Append($"Timer {item.TimerName} did not fire on time - LastCompletedTime = {item.Result!.LastCompletionTime} Last Expected Time = {item.Result!.LastExpectedCompletionTime}");
sb.Append("\n");
}
retval = new HealthCheckResult(HealthStatus.Unhealthy, sb.ToString(), null, itemDictionary);
}
else
{
retval = new HealthCheckResult(HealthStatus.Healthy, null, null, itemDictionary);
}
}
catch (Exception ex)
{
retval = new HealthCheckResult(HealthStatus.Unhealthy, "", ex, itemDictionary);
}
return(retval);
}
/// <summary>
/// Call this method at the end of your timer so it can checkpoint successful completion
/// </summary>
/// <typeparam name="T">The Type of your timertrigger</typeparam>
/// <returns></returns>
public async Task CheckpointMethodAsync <T>()
{
var blobContainer = _blobStorageFactory.GetBlobStorage(_options.AzureWebJobsStorageConnectionString, "azure-webjobs-hosts");
var status = new TimerHealthCheckStatus {
LastCheckpoint = _dateTimeService.CurrentDateTimeOffset
};
if (_options.IsProductionSlot)
{
var blobPath = GetBlobPath(typeof(T).FullName, _options);
await blobContainer.StoreBlobAsTextAsync(blobPath, JsonSerializer.Serialize(status)).ConfigureAwait(false);
if (string.IsNullOrWhiteSpace(_options.AzureWebSiteName))
{
_logger.LogWarning("It appears you are running locally. Timer will be checkpointed, but if you are not running locally, make sure you include the APPSETTING_WEBSITE_SITE_NAME to make sure this timer's checkpoint is unique to this instance");
}
}
else
{
_logger.LogWarning("Timer is not running in a production slot, timer will not be checkpointed");
}
}