mirror of
https://github.com/ninenines/cowboy.git
synced 2025-07-15 12:40:25 +00:00
68 lines
1.3 KiB
Text
68 lines
1.3 KiB
Text
|
= cowboy_req:binding(3)
|
||
|
|
|
||
|
|
== Name
|
||
|
|
|
||
|
|
cowboy_req:binding - Access a value bound from the route
|
||
|
|
|
||
|
|
== Description
|
||
|
|
|
||
|
|
[source,erlang]
|
||
|
|
----
|
||
|
|
binding(Name, Req) -> binding(Name, Req, undefined)
|
||
|
|
binding(Name, Req, Default) -> any() | Default
|
||
|
|
|
||
|
|
Name :: atom()
|
||
|
|
Req :: cowboy_req:req()
|
||
|
|
Default :: any()
|
||
|
|
----
|
||
|
|
|
||
|
|
Return the value for the given binding.
|
||
|
|
|
||
|
|
== Arguments
|
||
|
|
|
||
|
|
Name::
|
||
|
|
|
||
|
|
Desired binding name as an atom.
|
||
|
|
|
||
|
|
Req::
|
||
|
|
|
||
|
|
The Req object.
|
||
|
|
|
||
|
|
Default::
|
||
|
|
|
||
|
|
Default value returned when the binding is missing.
|
||
|
|
|
||
|
|
== Return value
|
||
|
|
|
||
|
|
By default the value is a case sensitive binary string, however
|
||
|
|
constraints may change the type of this value (for example
|
||
|
|
automatically converting numbers to integer).
|
||
|
|
|
||
|
|
== Changelog
|
||
|
|
|
||
|
|
* *2.0*: Only the value is returned, it is no longer wrapped in a tuple.
|
||
|
|
* *1.0*: Function introduced.
|
||
|
|
|
||
|
|
== Examples
|
||
|
|
|
||
|
|
.Get the username from the path
|
||
|
|
[source,erlang]
|
||
|
|
----
|
||
|
|
%% Route is "/users/:user"
|
||
|
|
Username = cowboy_req:binding(user, Req).
|
||
|
|
----
|
||
|
|
|
||
|
|
.Get the branch name, with a default
|
||
|
|
[source,erlang]
|
||
|
|
----
|
||
|
|
%% Route is "/log[/:branch]"
|
||
|
|
Branch = cowboy_req:binding(branch, Req, <<"master">>)
|
||
|
|
----
|
||
|
|
|
||
|
|
== See also
|
||
|
|
|
||
|
|
link:man:cowboy_req(3)[cowboy_req(3)],
|
||
|
|
link:man:cowboy_req:bindings(3)[cowboy_req:bindings(3)],
|
||
|
|
link:man:cowboy_req:host_info(3)[cowboy_req:host_info(3)],
|
||
|
|
link:man:cowboy_req:path_info(3)[cowboy_req:path_info(3)]
|