Conventional Defaults
Sails comes bundled with a suite of conventional HTTP middleware, ready to use. You can, of course, disable, override, rearrange, or append to it, but the pre-installed stack is perfectly acceptable for most apps in development or production. Below is a list of the standard HTTP middleware functions that comes bundled in Sails in the order they execute every time the server receives an incoming HTTP request:
| HTTP Middleware Key | Purpose |
|---|---|
| startRequestTimer | Allocates a variable in memory to hold the timestamp when the request began. This can be accessed and used by your app to provide diagnostic information about slow requests. |
| cookieParser * | Parses the cookie header into a clean object for use in subsequent middleware and your application code. |
| session * | Sets up a unique session object using your session configuration. |
| bodyParser | Parses parameters and binary upstreams (for streaming file uploads) from the HTTP request body using Skipper. |
| compress | Compresses response data using gzip/deflate. |
| methodOverride | Provides faux HTTP method support, letting you use HTTP verbs such as PUT or DELETE in places where the client doesn't support it (e.g. legacy versions of Internet Explorer.) If a request has a _method parameter set to "PUT", the request will be routed as if it was a proper PUT request. See Connect's methodOverride docs for more information if you need it. |
| poweredBy | Attaches an X-Powered-By header to outgoing responses. |
| $custom | Provides backwards compatibility for a configuration option from Sails v0.9.x. Since Sails v0.10 offers much more configuration flexibility for HTTP middleware, as long as you are not using sails.config.express.customMiddleware, you can confidently remove this item from the list. |
| router * | This is where the bulk of your app logic gets applied to any given request. In addition to running "before" handlers in hooks (e.g. csrf token enforcement) and some internal Sails logic, this routes requests using your app's explicit routes (in sails.config.routes) and/or route blueprints. |
| www * | Serves static files- usually images, stylesheets, scripts- in your app's "public" folder (configured in sails.config.paths, conventionally .tmp/public/) using Connect's static middleware. |
| favicon | Serves the browser favicon for your app if one is provided as /assets/favicon.ico. |
| 404 * | Handles requests which do not match any routes - triggers res.notFound() |
| 500 * | Handles requests which trigger an internal error (i.e. call Express's next(err)) - triggers res.serverError() |