/// <summary>
/// Executes action multiple times and reports error.
/// </summary>
/// <param name="asyncAction">Action to execute</param>
/// <param name="exceptionHandleStrategy">Handling strategy if exception has been thriown</param>
/// <param name="allowedAttempts">Show how many times action will be executed again in case of exception</param>
/// <param name="executionGroup">Indicates the group of actions to which current execution belongs. If something fails in group then notification will appear only once for all actions in group. Use null if action is group independent</param>
/// <returns></returns>
public static async Task ExecuteWithRetryAsync(Func <IAsyncExecutionContext, Task> asyncAction, int allowedAttempts = 1, string executionGroup = null)
{
if (allowedAttempts < 1)
{
throw new ArgumentOutOfRangeException(nameof(allowedAttempts));
}
var context = new AsyncExecutionContext();
context.WrapAction(asyncAction);
var workflow = new WorkflowWrappedExecutionContext
{
AllowedAttempts = allowedAttempts,
Context = context,
ExecutionGroup = executionGroup
};
if (executionGroup != null)
{
_groupedAsyncExecutions.AddOrUpdate(
executionGroup,
new ExecutionGroup <WorkflowWrappedExecutionContext> {
Name = executionGroup
},
(key, existingGroup) => existingGroup);
_groupedAsyncExecutions[executionGroup].Workflows.AddOrUpdate(workflow.Id, workflow, (key, value) => value);
}
await PerformExecutionWorkflowAsync(workflow).ConfigureAwait(false);
}
private static async Task <Exception> ExecuteMultipleTimesAsync(WorkflowWrappedExecutionContext workflow)
{
try
{
if (workflow.Context.TotalExecutionsCount == 0)
{
await workflow.Context.ExecuteFirstAsync().ConfigureAwait(false);
}
else
{
await workflow.Context.ExecuteAgainAsync().ConfigureAwait(false);
}
}
catch (Exception exception)
{
workflow.Context.Status = ExecutionContextStatus.Failed;
if (workflow.Context.ExecutionsCount >= workflow.AllowedAttempts)
{
return(exception);
}
else
{
return(await ExecuteMultipleTimesAsync(workflow).ConfigureAwait(false));
}
}
workflow.Context.Status = ExecutionContextStatus.Completed;
return(null);
}
private static async Task PerformExecutionWorkflowAsync(WorkflowWrappedExecutionContext workflow)
{
workflow.Context.ExecutionsCount = 0;
var exception = await ExecuteMultipleTimesAsync(workflow).ConfigureAwait(false);
if (exception == null)
{
DeleteContextFromGroupIfExists(workflow);
return;
}
var group = GetGroupForContext(workflow);
DeleteContextFromGroupIfExists(workflow);
}
private static void DeleteContextFromGroupIfExists(WorkflowWrappedExecutionContext workflow)
{
var group = GetGroupForContext(workflow);
if (group == null)
{
return;
}
if (group.Workflows.ContainsKey(workflow.Id))
{
group.Workflows.TryRemove(workflow.Id, out _);
}
if (group.Workflows.Any())
{
return;
}
_groupedAsyncExecutions.TryRemove(group.Name, out _);
}
private static ExecutionGroup <WorkflowWrappedExecutionContext> GetGroupForContext(WorkflowWrappedExecutionContext workflow)
{
return(!string.IsNullOrEmpty(workflow.ExecutionGroup) && _groupedAsyncExecutions.ContainsKey(workflow.ExecutionGroup)
? _groupedAsyncExecutions[workflow.ExecutionGroup]
: null);
}
