add wasm http middleware (#2520)

* add wasm http middleware

Signed-off-by: Loong Dai <loong.dai@intel.com>

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

Co-authored-by: Mark Fussell <markfussell@gmail.com>

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

Co-authored-by: Mark Fussell <markfussell@gmail.com>

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

Co-authored-by: Mark Fussell <markfussell@gmail.com>

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

Co-authored-by: Mark Fussell <markfussell@gmail.com>

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

Co-authored-by: Mark Fussell <markfussell@gmail.com>

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

Co-authored-by: Mark Fussell <markfussell@gmail.com>

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

Co-authored-by: Mark Fussell <markfussell@gmail.com>

* Update middleware-wasm.md

* Update middleware-wasm.md

* Update middleware-wasm.md

* Update middleware-wasm.md

* Update middleware-wasm.md

* Update _index.md

Co-authored-by: Yaron Schneider <schneider.yaron@live.com>
Co-authored-by: Mark Fussell <markfussell@gmail.com>

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

@@ -0,0 +1,61 @@
+---
+type: docs
+title: "WASM"
+linkTitle: "WASM"
+description: "Use WASM middleware in your HTTP pipeline"
+aliases:
+- /developing-applications/middleware/supported-middleware/middleware-wasm/
+---
+
+The WASM [HTTP middleware]({{< ref middleware.md >}}) component enables you to use a WASM module to handle requests and responses.
+Using WASM modules allow developers to write middleware components in any WASM supported language and extend Dapr using external files that are not pre-compiled into the `daprd` binary.
+
+WASM modules are loaded from a filesystem path. On Kubernetes, see [mounting volumes to the Dapr sidecar]({{> kubernetes-volume-mounts.md >}}) to configure a filesystem mount that can contain WASM modules.
+
+## Component format
+
+
+```yaml
+apiVersion: dapr.io/v1alpha1
+kind: Component
+metadata:
+  name: wasm
+spec:
+  type: middleware.http.wasm.basic
+  version: v1
+  metadata:
+  - name: path
+    value: "./hello.wasm"
+  - name: runtime
+    value: "wazero"
+```
+
+## Spec metadata fields
+
+| Field | Details | Example |
+|-------|---------|---------|
+| path | A relative or absolute path to the WASM module | "./hello.wasm" |
+| runtime | The WASM runtime of your WASM binary. Only `wazero` is supported | ["wazero"](https://github.com/tetratelabs/wazero) |
+
+
+## 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: wasm
+      type: middleware.http.wasm.basic
+```
+
+## Related links
+
+- [Middleware]({{< ref middleware.md >}})
+- [Configuration concept]({{< ref configuration-concept.md >}})
+- [Configuration overview]({{< ref configuration-overview.md >}})