Adds docs for Wasm output binding

Signed-off-by: Adrian Cole <adrian@tetrate.io>

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

@@ -0,0 +1,103 @@
+---
+type: docs
+title: "Wasm"
+linkTitle: "Wasm"
+description: "Detailed documentation on the WebAssembly binding component"
+aliases:
+- "/operations/components/setup-bindings/supported-bindings/wasm/"
+---
+
+## Overview
+
+WebAssembly is a way to safely run code compiled in other languages. Runtimes
+execute WebAssembly Modules (Wasm), which are most often binaries with a `.wasm`
+extension.
+
+The Wasm Binding allows you to invoke a program compiled to wasm, by passing
+commandline args or environment variables to it, similar to how you would with
+a normal subprocess. For example, you can satisfy an invocation using Python
+even though Dapr is written in go and running on a platform that doesn't have
+Python installed!
+
+The Wasm binary must be a program compiled with the WebAssembly System
+Interface (WASI). The binary can be a program you've written such as in Go, or
+an interpreter you use to run inlined scripts, such as Python.
+
+Minimally, a user must specify a Wasm binary compiled with the canonical WASI
+version `wasi_snapshot_preview1` a.k.a. `wasip1`, often abbreviated to `wasi`.
+
+If compiling yourself in Go 1.21+, this is `GOOS=wasip1 GOARCH=wasm`, whereas
+in TinyGo, Rust and Zig, this is the target `wasm32-wasi`.
+
+You can also re-use an existing binary. For example, [Wasm Language Runtimes](https://github.com/vmware-labs/webassembly-language-runtimes)
+distributes interpreters including PHP, Python and Ruby, already compiled to
+WASI.
+
+Wasm binaries are loaded from a URL. For example, a URL "file://rewrite.wasm"
+loads "rewrite.wasm" from the current directory of the process. On Kubernetes,
+see [mounting volumes to the Dapr sidecar]({{< ref kubernetes-volume-mounts.md >}})
+to configure a filesystem mount that can contain Wasm binaries.
+
+Dapr embeds [wazero](https://wazero.io) which loads programs compiled with the
+WebAssembly System Interface (WASI), obviating platform dependencies or forking
+otherwise needed to accomplish something like this.
+
+## Component format
+
+To configure a WebAssembly (Wasm) binding, create a component of type
+`bindings.wasm`. See [this guide]({{< ref "howto-bindings.md#1-create-a-binding" >}})
+on how to create and apply a binding configuration.
+
+```yaml
+apiVersion: dapr.io/v1alpha1
+kind: Component
+metadata:
+  name: wasm
+spec:
+  type: bindings.wasm
+  version: v1
+  metadata:
+  - name: url
+    value: "file://uppercase.wasm"
+```
+
+## Spec metadata fields
+
+| Field | Details                                                        | Required | Example        |
+|-------|----------------------------------------------------------------|----------|----------------|
+| url   | The URL of the resource including the Wasm binary to instantiate. The supported schemes include "file://". The path of a "file://" URL is relative to the Dapr process unless it begins with '/'. | true     | "file://hello.wasm" |
+
+
+## Binding support
+
+This component supports **output binding** with the following operations:
+
+- `execute`
+
+## Example request
+
+The `data` field, if present will be the program's STDIN. You can optionally
+pass metadata properties with each request:
+
+- `args` any CLI arguments, comma-separated. This excludes the program name.
+
+For example, if your Wasm binary is `ruby.wasm`, the following request would
+have the response data "Hello, salaboy"
+
+```json
+{
+  "operation": "execute",
+  "metadata": {
+    "args": "-ne,'print \"Hello, \"; print'"
+  },
+  "data": "salaboy"
+}
+```
+
+## Related links
+
+- [Basic schema for a Dapr component]({{< ref component-schema >}})
+- [Bindings building block]({{< ref bindings >}})
+- [How-To: Trigger application with input binding]({{< ref howto-triggers.md >}})
+- [How-To: Use bindings to interface with external resources]({{< ref howto-bindings.md >}})
+- [Bindings API reference]({{< ref bindings_api.md >}})

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

@@ -1,8 +1,8 @@
 ---
 type: docs
-title: "WASM"
-linkTitle: "WASM"
-description: "Use WASM middleware in your HTTP pipeline"
+title: "Wasm"
+linkTitle: "Wasm"
+description: "Use Wasm middleware in your HTTP pipeline"
 aliases:
 - /developing-applications/middleware/supported-middleware/middleware-wasm/
 ---

daprdocs/data/components/bindings/generic.yaml

@@ -142,3 +142,11 @@
   features:
     input: true
     output: true
+- component: Wasm
+  link: wasm
+  state: Alpha
+  version: v1
+  since: "1.11"
+  features:
+    input: false
+    output: true

daprdocs/data/components/middleware/http.yaml

@@ -43,8 +43,8 @@
   state: Stable
   version: v1
   description: Converts the body of the request to uppercase letters (demo)
-- component: WASM
+- component: Wasm
   link: /reference/components-reference/supported-middleware/middleware-wasm
   state: Alpha
   version: v1
-  description: Use WASM middleware in your HTTP pipeline
+  description: Use Wasm middleware in your HTTP pipeline