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Serving Static Files

If you’d like to serve files from a static directory, there’s a Middleware for that. It will match incoming requests to files in the directory, streaming those back to the client if they exist. By default, it serves from Public/ but you may pass a custom path in the initializer if you like. Consider a Public directory in your project with a few files. 
│
├── Public
│   ├── css
│   │   └── style.css
│   ├── js
│   │   └── app.js
│   ├── images
│   │   └── puppy.png
│   └── index.html
│
├── Sources
├── Tests
└── Package.swift
You could use the following code to serve files from that directory. 
app.useAll(StaticFileMiddleware())
Now, assets in the Public/ directory can be requested. 
http://localhost:3000/index.html
http://localhost:3000/css/style.css
http://localhost:3000/js/app.js
http://localhost:3000/images/puppy.png
http://localhost:3000/ (by default, will return any `index.html` file)
Note: The given directory is relative to your server’s working directory. If you are using Xcode, be sure to set a custom working directory for your project where the static file directory is.