@mgfx/express-middleware
Express middleware for integration with mgFx applications.
Features
- Creates per-route mgFx contexts that includes
http.methodandhttp.pathContext Values automatically - Run mgFx processes in that Context via
req.mgFx.run() - Run an arbitrary Future and fork it's resolution value or rejection reason to the HTTP response via
req.mgFx.fork - Run a Task and fork it to the Response in a single shot via
req.mgFx.runF()
Usage
- Install
@mgfx/express-middlewareinto your existing mgFx/Express application:
$ yarn add @mgfx/express-middleware
- Add the Middleware to an Express application:
import express from 'express';
import { localConnector } from 'mgfx';
import { expressMiddleware } from '@mgfx/express-middleware';
const connector = localConnector();
const app = express();
app.use(expressMiddleware({ connector }));
/** mgFx Task definitions, Express routes, etc */- Use
req.mgFxwithin your Express handlers:
import { after, fork, map } from 'fluture';
// Use `req.mgFx.run` to run a Task within the context of the current HTTP request:
app.get('/run/:name', (req, res, next) => {
// `myTask` will be invoked in a Context that contains the values:
// { 'http.path': '/run/:name', 'http.method': 'GET' }
req.mgFx
.run(myTask({ name: req.params.name }))
// Explicitly use `Fluture.fork` to run this Future
.pipe(fork(error => next(error)(result => res.send(result))));
});
// Use `req.mgFx.fork` to run an arbitrary Future and send it's value/error to the Response:
app.get('/fork/:name', req => {
after(100)(`Hello ${name}!`).pipe(req.mgFx.fork);
});
// Use `req.mgFx.runF` to run a Task and send it's output directly to the response:
app.get('/runF/:name', req => {
req.mgFx.runF(myTask({ name: req.params.name }));
});
// Use `req.mgFx.run` and `req.mgFx.fork` to run a Task, do some intermediate operation, and send the result to the
// Response:
app.get('/complex/:name', req => {
req.mgFx
.run(myTask({ name: req.params.name }))
.pipe(map(result => result.length))
.pipe(req.mgFx.fork);
});