Add router alias middleware (#3180)

* Add router alias middleware

Signed-off-by: yaron2 <schneider.yaron@live.com>

* Update daprdocs/content/en/reference/components-reference/supported-middleware/middleware-routeralias.md

Signed-off-by: Mark Fussell <markfussell@gmail.com>

* Update daprdocs/content/en/reference/components-reference/supported-middleware/middleware-routeralias.md

Signed-off-by: Mark Fussell <markfussell@gmail.com>

---------

Signed-off-by: yaron2 <schneider.yaron@live.com>
Signed-off-by: Mark Fussell <markfussell@gmail.com>
Co-authored-by: Mark Fussell <markfussell@gmail.com>

daprdocs/content/en/reference/components-reference/supported-middleware/middleware-routeralias.md

@@ -0,0 +1,57 @@
+---
+type: docs
+title: "Router alias http request routing"
+linkTitle: "Router Alias"
+description: "Use router alias middleware to alias arbitrary http routes to Dapr endpoints"
+aliases:
+- /developing-applications/middleware/supported-middleware/middleware-routeralias/
+---
+
+The router alias HTTP [middleware]({{< ref middleware.md >}}) component allows you to convert arbitrary HTTP routes arriving to Dapr to valid Dapr API endpoints.
+
+## Component format
+
+The router alias middleware metadata contains name/value pairs, where the name describes the HTTP route to expect, and the value describes the corresponding Dapr API the request should be sent to.
+
+```yaml
+apiVersion: dapr.io/v1alpha1
+kind: Component
+metadata:
+  name: routeralias 
+spec:
+  type: middleware.http.routeralias
+  version: v1
+  metadata:
+  - name: "/v1.0/mall/activity/info"
+    value: "/v1.0/invoke/srv.default/method/mall/activity/info"
+  - name: "/v1.0/hello/activity/{id}/info"
+    value: "/v1.0/invoke/srv.default/method/hello/activity/info"
+  - name: "/v1.0/hello/activity/{id}/user"
+    value: "/v1.0/invoke/srv.default/method/hello/activity/user"
+```
+
+Example:
+
+An incoming HTTP request for `/v1.0/mall/activity/info?id=123` is transformed into `/v1.0/invoke/srv.default/method/mall/activity/info?id=123`.
+
+## Dapr configuration
+
+To be applied, the middleware must be referenced in [configuration]({{< ref configuration-concept.md >}}). See [middleware pipelines]({{< ref "middleware.md#customize-processing-pipeline">}}).
+
+```yaml
+apiVersion: dapr.io/v1alpha1
+kind: Configuration
+metadata:
+  name: appconfig
+spec:
+  httpPipeline:
+    handlers:
+    - name: routeralias 
+      type: middleware.http.routeralias
+```
+
+## Related links
+
+- [Middleware]({{< ref middleware.md >}})
+- [Configuration concept]({{< ref configuration-concept.md >}})
+- [Configuration overview]({{< ref configuration-overview.md >}})

daprdocs/data/components/middleware/http.yaml

@@ -33,6 +33,11 @@
   state: Alpha
   version: v1
   description: Use RouterChecker middleware to block invalid http request routing
+- component: Router Alias
+  link: /reference/components-reference/supported-middleware/middleware-routeralias
+  state: Alpha
+  version: v1
+  description: Use Router Alias to map arbitrary HTTP routes to valid Dapr API endpoints
 - component: Uppercase
   link: /reference/components-reference/supported-middleware/middleware-uppercase
   state: Stable