ToolWheel.Extensions.JobManager.Conditions 1.0.0

ToolWheel.Extensions.JobManager.ExecutionConditions

Pre-execution condition evaluators for the ToolWheel Job Manager. Ships conditions that prevent a job from running when its task limit is reached, when a dependency job is still active, or when the configured rate limit is exceeded.

Package Info

Auto Configuration

This package ships JobManagerExecutionConditionModule implementing IJobManagerModulDescription. When AddJobManager() scans loaded assemblies at startup it automatically:

1. Registers IJobRateLimitTracker as a singleton implementation of JobRateLimitTracker.
2. Adds JobTaskLimiterCondition as an IExecutionCondition.
3. Adds JobDependencyCondition as an IExecutionCondition.
4. Adds JobRateLimitCondition as an IExecutionCondition.
5. Adds JobRateLimitMiddleware to the execution pipeline.

No manual registration is required � referencing the package is sufficient.

Task Limit

Prevents a job from creating new tasks when the configured maximum number of concurrent pending or running tasks is already reached.

Configuration

jobs.Add("import-job", worker.RunImport)
    .Name("Data Import")
    .Enabled()
    .TaskLimit(3); // at most 3 concurrent tasks

A limit of 0 or null means no limit is enforced.

How It Works

1. When a job is configured with .TaskLimit(count), the JobTaskLimitFeature is applied via IJobExecutionConditionService.Add<JobTaskLimitFeature>().
2. Before each execution, JobTaskLimiterCondition retrieves the feature and counts active tasks (status Pending or Running) via IJobTaskService.ReadByJob(job, ...).
3. If the count >= limit, the execution context is set to not ready with the message "Task limit reached".

Job Execution Dependencies

Prevents a job from starting while one or more other jobs still have active (Pending or Running) tasks.

Configuration

jobs.Add("import-job", worker.ImportData)
    .Name("Data Import")
    .Enabled();

jobs.Add("cleanup-job", worker.Cleanup)
    .Name("Cleanup")
    .Enabled()
    .DependsOn("import-job");         // blocked while import-job is active

Multiple dependencies and combinations with other conditions are supported:

jobs.Add("report-job", worker.GenerateReport)
    .Name("Report")
    .Enabled()
    .TaskLimit(1)
    .DependsOn("import-job", "sync-job");

How It Works

1. When a job is configured with .DependsOn(jobIds), the JobDependencyFeature is applied via IJobExecutionConditionService.Add<JobDependencyFeature>().
2. Before each execution, JobDependencyCondition iterates the registered dependency job IDs.
3. For each dependency, it resolves the job instance via IJobService.FindById() and queries active tasks via IJobTaskService.ReadByJob(dep, Pending, Running).
4. If any dependency has at least one active task, the execution context is set to not ready with the message "A dependent job is still running" and evaluation stops early.

Rate Limiting

Prevents a job from being started too frequently within a rolling time window.

Configuration

jobs.Add("api-sync-job", worker.SyncWithApi)
    .Name("API Sync")
    .Enabled()
    .RateLimit(maxStarts: 10, timeWindow: TimeSpan.FromHours(1));

Combine with other conditions:

jobs.Add("heavy-job", worker.ProcessHeavyWork)
    .Name("Heavy Job")
    .Enabled()
    .TaskLimit(1)
    .RateLimit(maxStarts: 5, timeWindow: TimeSpan.FromMinutes(10));

A maxStarts of 0 or less disables rate limiting for the job. The time window is rolling (continuous), not fixed intervals.

How It Works

1. When a job is configured with .RateLimit(maxStarts, timeWindow), the JobRateLimitFeature is applied via IJobExecutionConditionService.Add<JobRateLimitFeature>().
2. Before each execution, JobRateLimitCondition retrieves the feature and calls IJobRateLimitTracker.CanStart(job, feature) to check if the job can be started within the rolling window.
3. If the number of starts within the window has reached the limit, the execution context is set to not ready with the message "Rate limit reached".
4. When a task is about to start, JobRateLimitMiddleware records the start time via IJobRateLimitTracker.RecordStart(job).
5. The tracker automatically purges start times that fall outside the rolling window when evaluating CanStart().

API Reference

Extension Methods (IJobDescriptionBuilder)

Services & Extension Methods

IJobExecutionConditionService Extension Methods

IJobRateLimitTracker

Conditions

Middleware

Features