This module provides middleware for mounting other applications on a specific URI path or virtual host.

Applying this middleware adds a mount method to the application. The mount method takes a path or virtual host specification and an application as arguments. If the spec is a string, it is interpreted as the URI path on which the app will be mounted. If it is an object, it may contain path or host properties that will be matched against the URI path and Host header of incoming requests. Note that virtual host based mounting has not been tested so far.

The mount method accepts an optional third boolean noRedirect argument. If set to true it will disable redirecting GET requests to the mount base URL without a trailing slash to the same URL with trailing slash. By default, mount middleware will send a redirect to the mount URL with trailing slash.

Mounting one application within another causes the scriptName and pathInfo properties in the request object to be adjusted so that the mounted application receives the same pathInfo as if it was the main application. This means that forward and reverse request routing will usually work as expected.

This middleware maintains an index mapping applications to mount points which can be accessed using the lookup function. The [stick/helpers][helpers] module provides higher level functions for this which include support for the route middleware.