Create goal Build Your Own Express

_goals/430-Build_Your_Own_Express.md

@@ -0,0 +1,81 @@
+---
+authors:
+- "jason00111"
+team_size: 1
+goal_id: 430
+title: Build Your Own Express
+created_at: '2017-06-02T16:49:40.602Z'
+labels:
+- practice
+- draft
+level: '2'
+published: false
+redirect_from: '/goals/430'
+---
+
+# Build Your Own Express
+
+## Challenge Rating
+
+This goal will likely be within your ZPD if you...
+
+- Have used node.js
+- Have used express.js
+- Are interested in better understanding express middleware and routing
+
+## Description
+
+Express is a framework for building web apps and web API's using node.js.
+
+In this goal, you will build a simplified clone of express.
+
+## Context
+
+After doing this goal you will have a better understanding of how express handles middleware and routing.
+
+## Specifications
+
+- [ ] An express app can be initialized using
+```
+const express = require('./myExpress')
+const app = express()
+```
+- [ ] `app` has `get`, `post`, `put`, and `delete` functions which define routing (how an app responds to api endpoints) using this format `app.METHOD(PATH, HANDLER)`. See [this](https://expressjs.com/en/starter/basic-routing.html).
+- [ ] Middleware can be added to the app using `app.use` in this format:
+```
+app.use(function (req, res, next) {
+  // do middleware things here
+  next()
+})
+```
+- [ ] Middleware is run in the order that is defined in the code.
+- [ ] The npm packages [body-parser](https://www.npmjs.com/package/body-parser) and [cookie-parser](https://www.npmjs.com/package/cookie-parser) can be added as middleware to an app using `app.use`.
+- [ ] Query strings are parsed and available at `req.query` (see [this](https://expressjs.com/en/4x/api.html#req.query))
+- [ ] The path is available at `req.path` (see [this](https://expressjs.com/en/4x/api.html#req.path))
+- [ ] Route parameters can be defined with a colon by the developer in the `PATH` of `app.METHOD` functions like this `/users/:userId/books/:bookId`. Parameters are available at `req.params`. See [this](https://expressjs.com/en/guide/routing.html#route-parameters)
+- [ ] `res.send` can send plain text, html, or json (see [this](https://expressjs.com/en/4x/api.html#res.send))
+- [ ] Response status can be set like this (see [this](https://expressjs.com/en/4x/api.html#res.status))
+```
+res.status(200)
+res.send('Hello, World!')
+```
+or this
+```
+res.status(200).send('Hello, World!')
+```
+- [ ] A json response can be sent with `res.json` (see [this](https://expressjs.com/en/4x/api.html#res.json))
+- [ ] HTTP `Content-Type` header can be set with `res.type` (see [this](https://expressjs.com/en/4x/api.html#res.type))
+- [ ] HTTP headers can be set with `res.set` (see [this](https://expressjs.com/en/4x/api.html#res.set))
+- [ ] An HTML file can be sent with `res.sendFile(pathToFile)`
+- [ ] Middleware for serving static files is available at `express.static(dirPath)` (see [this](https://expressjs.com/en/4x/api.html#express.static))
+- [ ] `app`'s `get`, `post`, `put`, and `delete` functions can take a regular expression as first argument to match endpoints
+- [ ] The artifact produced is properly licensed, preferably with the [MIT license][mit-license].
+
+## Resources
+
+- [Express documentation](https://expressjs.com)
+- [node.js built-in url parser](https://nodejs.org/api/url.html)
+- [node.js built-in query string parser](https://nodejs.org/api/querystring.html)
+- [node.js built-in http server](https://nodejs.org/api/http.html)
+
+[mit-license]: https://opensource.org/licenses/MIT