koa-contrib-pathstringstartswith

a koa middleware, call an user defined middleware if ctx.path path string starts with a give prefix

This is a replacement for koa-mount.

How it works

It accept two params, path prefix, middleware. If the app's ctx.path starts with path prefix, then call the middleware.

It do so by a simple string compare. Chart below shows its behavior.

| ctx.path | prefix | call middleware (Y/N) | |----------------|---------|-----------------------| | / | /api | N | | /api | /api | Y | | /api/ | /api | Y | | /api | /api/ | N | | /api/ | /api/ | Y | | /api/v1 | /api/ | Y | | /api/v1 | /api/v | Y | | /api/v2 | /api/v2 | Y | | /api/v2.0 | /api/v2 | Y | | /api/v21 | /api/v2 | Y | | /images | /image | Y | | /images/flower | /image/ | Y |

Usage

If you just want a simple starts with compare, use it. Otherwise use koa-contrib-pathstartswith instead.

Install via npm or yarn.

# for npm
npm i --save koa-contrib-startswith
# for yarn
yarn add koa-contrib-startswith

Use as a Koa middleware in your app.

// import it
const startsWith = require('koa-contrib-startswith')

// if ctx.path starts with `api/v1`, then call myMiddleware1
app.use(startsWith('/api/v1', myMiddleware1))

// if ctx.path starts with `api/v2`, then call myMiddleware2
app.use(startsWith('/api/v2', myMiddleware2))

Compare to koa-mount

• This koa middleware just call your user-defined middlewares according the ctx.path's prefix, it does not re-write ctx.path, so the path your middleware get is as is.
• This middleware do not mount Koa application.
• It's simple and easy to use.

LICENSE

The MIT License.