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MiddlewareSequence class

A sequence implementation using middleware chains


export declare class MiddlewareSequence implements SequenceHandler 

Implements: SequenceHandler


Constructor Modifiers Description
(constructor)(context, invokeMiddleware, options)   Constructor: Injects InvokeMiddleware and InvokeMiddlewareOptions


Property Modifiers Type Description
defaultOptions static InvokeMiddlewareOptions  
invokeMiddleware readonly InvokeMiddleware  
options readonly InvokeMiddlewareOptions  


Method Modifiers Description
handle(context)   <p>Runs the default sequence. Given a handler context (request and response), running the sequence will produce a response or an error.</p><p>Default sequence executes these groups of middleware:</p><p>- cors: Enforces CORS - openApiSpec: Serves OpenAPI specs - findRoute: Finds the appropriate controller method, swagger spec and args for invocation - parseParams: Parses HTTP request to get API argument list - invokeMethod: Invokes the API which is defined in the Application controller method</p><p>In front of the groups above, we have a special middleware called sendResponse, which first invokes downstream middleware to get a result and handles the result or error respectively.</p><p>- Writes the result from API into the HTTP response (if the HTTP response has not been produced yet by the middleware chain. - Catches error logs it using ‘logError’ if any of the above steps in the sequence fails with an error.</p>