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MiddlewareSequence class
A sequence implementation using middleware chains
Signature:
export declare class MiddlewareSequence implements SequenceHandler
Implements: SequenceHandler
Constructors
| Constructor | Modifiers | Description |
|---|---|---|
| (constructor)(context, invokeMiddleware, options) | Constructor: Injects InvokeMiddleware and InvokeMiddlewareOptions |
Properties
| Property | Modifiers | Type | Description |
|---|---|---|---|
| defaultOptions | static |
InvokeMiddlewareOptions | |
| invokeMiddleware | readonly |
InvokeMiddleware | |
| options | readonly |
InvokeMiddlewareOptions |
Methods
| 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> |