A tiny route/api semantic versioning library for Koa and Express.
A tiny route/api semantic versioning library for Koa and Express.
npm install route-v
Gets the version from the URL (originalUrl) and expects Routes/APIs to look like Koa or Express middleware.
const Koa = require('koa');
const Router = require('koa-router');
const {v} = require('route-v')();
// This regex will check if the url has a version number in it.
const baseUrl = '/(v\\d+.\\d+.\\d+)';
const router = new Router({
prefix: `${baseUrl}/greetings`
});
router
.get('/', v({
// Note that the order matters
// Key: any range accepted by semver
// value: any function
'<1.x': ctx => ctx.body = 'hello', // if <1.x
'^1.0.0': ctx => ctx.body = 'hola', // else if ^1.0.0
// Matches any other valid version
'*': ctx => ctx.body = 'hi' // else
}));
const app = new Koa();
app
.use(router.allowedMethods({throw: true}))
.use(router.routes())
.listen(3000);
Behavior:
curl localhost:3000/v0.0.0/greetings // hello
curl localhost:3000/v1.0.0/greetings // hola
curl localhost:3000/v2.0.0/greetings // hi
// ... some omitted setup code
const {versionChecker} = require('route-v')();
const vChecker = versionChecker((isSatisfied, {userVersion, predicate, range}) =>
(ctx, next) => {
if(!isSatisfied) {
ctx.throw(400, `Version ${userVersion} is not ${predicate} range ${range}`);
}
return next();
});
router
.use(vChecker('<5.x'));
exports.app = new Koa();
exports.app
.use(router.allowedMethods({throw: true}))
.use(router.routes())
.listen(3000);
Behavior:
curl localhost:3000/v6.0.0/greetings // Version 6.0.0 is not compliant with version <5.x
If you want to use the header instead of the url.
const {valid} = require('semver');
// Points to the object "headers" from the first argument of your function (ctx in koa, req in express)
// and returns the value of the key x-api-version
const versionExtractor = ctxOrReq => valid(ctxOrReq.headers['x-api-version']);
const {v} = routeV({versionExtractor});
By default, an error will be thrown if the version requested was not found.
// This is for Koa, for express, a similar middleware can be passed
const versionNotFoundErrorHandler = ctx => ctx.throw(400, 'Version not found');
const {v} = routeV({versionNotFoundErrorHandler});
npm test
Since the insertion order matters but it is not guaranteed for integers, the library assumes you know what you are doing when using integers as ranges. https://bugs.chromium.org/p/v8/issues/detail?id=164
Credits: Kudus to Avaq, his expertise have been extremely helpful.