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invokeExpressMiddleware() function

Invoke a list of Express middleware handler functions

Signature:

export declare function invokeExpressMiddleware(middlewareCtx: MiddlewareContext, ...handlers: ExpressRequestHandler[]): ValueOrPromise<boolean>;

Parameters

Parameter Type Description
middlewareCtx MiddlewareContext Middleware context
handlers ExpressRequestHandler[] A list of Express middleware handler functions

Returns:

ValueOrPromise<boolean>

Example

import cors from 'cors';
import helmet from 'helmet';
import morgan from 'morgan';
import {MiddlewareContext, invokeExpressMiddleware} from '@loopback/express';

// ... Either an instance of `MiddlewareContext` is passed in or a new one
// can be instantiated from Express request and response objects

const middlewareCtx = new MiddlewareContext(request, response);
const finished = await invokeExpressMiddleware(
  middlewareCtx,
  cors(),
  helmet(),
  morgan('combined'));

if (finished) {
  // Http response is sent by one of the middleware
} else {
  // Http response is yet to be produced
}