Document updated on Oct 25, 2022
URL Rewrite
The url-rewrite
plugin allows you to define a set of URLs or regular expressions that are handled by an endpoint of your choice. In other words, this plugin allows you to declare additional URLs other than the ones defined under the endpoints
configuration, used as aliases of existing endpoints.
URL rewrite configuration
You need to define a URL dictionary specifying how requests map to the existing endpoints to use the plugin. There are two diferent ways of declaring rewrites:
literal
: The literal match takes precedence and is checked first. If the requested URL is exactly the one defined in the map, then the redirection happens.regexp
: The regexp expressions are checked in sequence when there are no literal matches. You can use the capturing groups in the endpoint definition.
{
"version": 3,
"plugin": {
"pattern":".so",
"folder": "/opt/krakend/plugins/"
},
"extra_config": {
"plugin/http-server": {
"name": ["url-rewrite", "some-other-plugin-here" ],
"url-rewrite": {
"literal": {
"/hi-there": "/hello",
"/whatsup": "/hello"
},
"regexp": [
["/hi-there/([\w\d\s]+)/bar", "/hello/${1}"],
["/whats/up/([\w\d\s]+)", "/hey/${1}/whatsup"]
]
}
}
}
}
The configuration options inside the url-rewrite
plugin are:
Fields of URL rewrite
Minimum configuration needs any of:
literal
, or
regexp
literal
object- A map with the exact desired url and its mapping to an endpoint. If the endpoint has
{placeholders}
you need to write them, but the literal value{placeholders}
is passed.Example:{"/hi-there":"/hello","/whatsup":"/hello"}
regexp
array- A list of lists, containing the regular expression that defines the URL to be rewritten, and its endpoint destination. You can use the capturing groups with the syntax
${1}
,${2}
, etc.
All regular expressions are evaluated in order. The first matching expression will rewrite and exit.