MiddlewarePipeline class

Enhanced middleware pipeline with priority-based execution and better error handling.

This class manages a collection of middleware handlers that process HTTP requests in a specific order based on their priority levels. It supports:

Priority-based execution (global -> routing -> auth -> preprocessing -> business -> terminating)
Named middleware for easy reference and ordering
Error handling with terminating middleware
Dynamic addition/removal of middleware
Before/after insertion relative to named middleware

Example usage:

final pipeline = MiddlewarePipeline();

// Add middleware with different priorities
pipeline.add((req, res, next) async {
  print('Global middleware');
  await next();
}, priority: MiddlewarePriority.global, name: 'logger');

pipeline.add((req, res, next) async {
  print('Auth middleware');
  await next();
}, priority: MiddlewarePriority.auth, name: 'auth');

// Process request
await pipeline.process(request, response);

Constructors

MiddlewarePipeline()

Properties

count → int: Gets the count of middleware in the pipeline.
no setter
hashCode → int: The hash code for this object.
no setterinherited
isEmpty → bool: Checks if the pipeline is empty.
no setter
isNotEmpty → bool: Checks if the pipeline has any middleware.
no setter
middleware → List<Middleware>: Gets all middleware in the pipeline.
no setter
middlewareNames → List<String>: Gets all middleware names.
no setter
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited

Methods

add(MiddlewareHandler handler, {MiddlewarePriority priority = MiddlewarePriority.business, String? name}) → void: Adds a middleware handler function to the pipeline.
addAfter(String targetName, MiddlewareHandler handler, {String? name}) → void: Adds a middleware after a specific named middleware.
addAll(List<MiddlewareHandler> handlers, {MiddlewarePriority priority = MiddlewarePriority.business}) → void: Adds multiple middleware handlers to the pipeline.
addBefore(String targetName, MiddlewareHandler handler, {String? name}) → void: Adds a middleware before a specific named middleware.
addConditional(MiddlewareHandler handler, {required bool condition(Request request), MiddlewarePriority priority = MiddlewarePriority.business, String? name}) → void: Executes middleware conditionally based on a predicate.
addMiddleware(Middleware middleware) → void: Adds a full middleware object to the pipeline.
addMiddlewares(List<Middleware> middlewares) → void: Adds multiple middleware objects to the pipeline.
clear() → void: Clears all middleware from the pipeline.
getByName(String name) → Middleware?: Gets a middleware by name.
getGroup(String name) → List<Middleware>: Gets a registered group of middleware.
getMiddlewareByPriority(MiddlewarePriority priority) → List<Middleware>: Gets middleware by priority level.
group(String name, List<Middleware> middlewares) → void: Registers a group of middleware.
hasMiddleware(String name) → bool: Checks if a named middleware exists.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
process(Request request, ResponseContract response) → Future<void>: Processes the request through the middleware pipeline.
remove(String name) → void: Removes a middleware by name.
toString() → String: A string representation of this object.
inherited
useGroup(String name) → void: Adds a registered group of middleware to the pipeline.

Operators

operator ==(Object other) → bool: The equality operator.
inherited

Static Methods

execute(List<Middleware> middlewares, Request request, ResponseContract response, FutureOr<void> finalHandler(Request, ResponseContract)) → Future<void>: Executes a list of middleware in order, followed by a final handler.