composite-service-http-gateway v1.0.0
composite-service-http-gateway
Configurable http gateway service for use with composite-service
Install
$ npm install composite-service composite-service-http-gatewayUsage
Call configureHttpGateway with a HttpGatewayConfig object
to get a ServiceConfig object you can use in your CompositeServiceConfig.
const { startCompositeService } = require("composite-service");
const { configureHttpGateway } = require("composite-service-http-gateway");
const apiPort = process.env.API_PORT || 8000;
const webPort = process.env.API_PORT || 8001;
const port = process.env.PORT || 3000;
startCompositeService({
services: {
api: {
cwd: `${__dirname}/api`,
command: "node server.js",
env: { PORT: apiPort },
ready: ctx => ctx.onceTcpPortUsed(apiPort),
},
web: {
cwd: `${__dirname}/web`,
command: `next start --port ${webPort}`,
ready: ctx => ctx.onceTcpPortUsed(webPort),
},
gateway: configureHttpGateway({
dependencies: ["api", "web"],
port,
routes: {
"/admin": { static: { root: `${__dirname}/admin/build` } },
"/api": { proxy: { target: `http://localhost:${apiPort}` } },
"/": { proxy: { target: `http://localhost:${webPort}` } },
},
}),
},
});The HttpGatewayConfig object defines
a port, a host (optional), a collection of routes, and an onReady hook (optional).
Any additional properties will be included in the returned ServiceConfig (except command or ready).
Routes
The central property of HttpGatewayConfig is routes.
In this object, each key is an absolute URL path,
and each value is configuration of how to handle requests to that path and all it's sub-paths.
Note that the order of entries is significant because
requests will be handled by the first matching route,
hence putting the / route last in the example above.
Handlers
There are currently two "handlers", or ways requests can be handled:
| # | identifier | middleware | description |
|---|---|---|---|
| 1 | proxy | http-proxy-middleware | Proxy to another http service, typically a sibling composed service |
| 2 | static | serve-static | Serve static files from the filesystem |
Handler config objects are mostly just passed along to the underlying middleware, so please refer to the above-linked middleware documentation for details on configuration options.
That said, the following handler config defaults are updated for convenience:
| handler | config | original default | updated default | reason |
|---|---|---|---|---|
proxy | logLevel | "info" | "warn" | reduce noise |
proxy | ws | false | true | support WebSocket connections out-of-the-box |
Using functions in handler configuration
Non-json-serializable values like functions and regular expressions can be used in handler configuration
thanks to serialize-javascript.
This however comes with caveats:
1. Functions must be pure (i.e. must not refer to variables outside it's definition)
2. require()s inside a function will be resolved fromnode_modules/composite-service-http-gateway/server/server.js (3 levels)