Add cowboy:set_env/3

guide/middlewares.md

@@ -58,6 +58,9 @@ will not process any subsequent requests on this connection.
 The middlewares that come with Cowboy may define or require other
 environment values to perform.
 
+You can update the environment by calling the `cowboy:set_env/3`
+convenience function, adding or replacing a value in the environment.
+
 Routing middleware
 ------------------
 

guide/routing.md

@@ -242,3 +242,17 @@ cowboy:start_http(my_http_listener, 100,
 
 Note that this function will return `{error, badarg}` if the structure
 given is incorrect.
+
+Live update
+-----------
+
+You can use the `cowboy:set_env/3` function for updating the dispatch
+list used by routing. This will apply to all new connections accepted
+by the listener.
+
+``` erlang
+cowboy:set_env(my_http_listener, dispatch,
+    cowboy_router:compile(Dispatch)).
+```
+
+Note that you need to compile the routes before updating.

guide/toc.md

@@ -8,10 +8,11 @@ Cowboy User Guide
    *  Getting started
  *  [Routing](routing.md)
    *  Purpose
-   *  Dispatch list
-   *  Match rules
-   *  Bindings
+   *  Structure
+   *  Match syntax
    *  Constraints
+   *  Compilation
+   *  Live update
  *  [Handlers](handlers.md)
    *  Purpose
    *  Protocol upgrades