Pipeline Registration

PipeForge uses dependency injection to resolve both pipeline steps and their runners, and leverages lazy instantiation to avoid constructing steps that will never be executed - either due to short-circuiting, cancellation tokens, or runtime exceptions.

This section describes how to register pipelines using the built-in extension methods provided by PipeForge.

Register a Pipeline

The most common way to register a pipeline is by using the AddPipeline extension methods on IServiceCollection. These methods automatically discover and register all pipeline steps for a given context and step interface by scanning the provided assemblies. An appropriate runner is also registered, allowing you to resolve and execute the pipeline easily.

Method Signature

public static IServiceCollection AddPipeline<TContext, TStepInterface, TRunnerInterface>(
    this IServiceCollection services,
    IEnumerable<Assembly> assemblies,
    ServiceLifetime lifetime,
    string[]? filters)
    where TContext : class
    where TStepInterface : IPipelineStep<TContext>
    where TRunnerInterface : IPipelineRunner<TContext, TStepInterface>
{ }

Parameters

Parameter	Required	Description
TContext	✅	The context class shared across all steps in the pipeline.
TStepInterface		The interface used to identify pipeline steps. Defaults to IPipelineStep<TContext>.
TRunnerInterface		The interface used to resolve the pipeline runner. Defaults to IPipelineRunner<TContext, TStepInterface>.
assemblies		Assemblies to scan for steps. If not provided, AppDomain.CurrentDomain is used.
lifetime		The DI lifetime for steps and the runner. Defaults to ServiceLifetime.Transient.
filters		Optional filters to limit which steps are registered.

Examples

Here are some examples of how to use the various overloads of AddPipeline:

// Minimal registration using default step and runner interfaces
services.AddPipeline<SampleContext>();

// Register with a custom step interface
services.AddPipeline<SampleContext, ISampleContextStep>();

// Register with a custom step and custom runner interface
services.AddPipeline<SampleContext, ISampleContextStep, ISampleContextRunner>();

// Register with specific assemblies and a scoped lifetime
services.AddPipeline<SampleContext, ISampleContextStep>(
    new[] { typeof(MyStep).Assembly },
    ServiceLifetime.Scoped);

// Register with multiple filters
services.AddPipeline<SampleContext, ISampleContextStep>(
    new[] { typeof(MyStep).Assembly },
    new[] { "Development", "Testing" });

Register a Single Step

If you prefer to manually register individual steps, or want fine-grained control over registration, use the AddPipelineStep extension method.

Warning

When registering steps individually:

• The PipelineStep attribute on the step is neither required nor used.
• No pipeline runner is registered. You will need to register it yourself.

Method Signature

public static IServiceCollection AddPipelineStep<TStep, TStepInterface>(
    this IServiceCollection services,
    ServiceLifetime lifetime = ServiceLifetime.Transient)
    where TStep : class, TStepInterface
    where TStepInterface : class, IPipelineStep
{ }

Parameters

Parameter	Description	Required
TStep	The concrete step class to register.	✅
TStepInterface	The interface used to register the step. Defaults to IPipelineStep<TContext> if not provided.	❌
lifetime	The DI lifetime for the step. Defaults to ServiceLifetime.Transient.	❌

If TStepInterface is not provided, the method will attempt to infer the context type from TStep.