Module plugin 

Plugin system for extending host capabilities.

This module provides the plugin framework that allows the wasmcloud host to support different WASI interfaces and capabilities. Plugins implement specific functionality that components can use through standard interfaces.

Plugin Architecture

Plugins are Rust types that implement the HostPlugin trait. They:

• Declare which WIT interfaces they provide via HostPlugin::world
• Bind to components that need their capabilities via [HostPlugin::bind_component]
• Can participate in workload lifecycle events
• Are automatically linked into the wasmtime runtime

Built-in Plugins

The crate provides several built-in plugins for common WASI interfaces:

• wasi_http - HTTP server capabilities (wasi:http/incoming-handler)
• wasi_config - Runtime configuration (wasi:config/runtime)
• wasi_blobstore - Object storage (wasi:blobstore)
• wasi_keyvalue - Key-value storage (wasi:keyvalue)
• wasi_logging - Structured logging (wasi:logging)

Modules

wasi_blobstore

WASI Blobstore Memory Plugin

wasi_config

Runtime configuration plugin for WebAssembly components.

wasi_http

HTTP server plugin for handling incoming HTTP requests.

wasi_keyvalue

WASI KeyValue Memory Plugin

wasi_logging

Structured logging plugin for WebAssembly components.

Traits

HostPlugin

The HostPlugin trait provides an interface for implementing built-in plugins for the host. A plugin is primarily responsible for implementing a specific WitWorld as a collection of imports and exports that will be directly linked to the workload’s wasmtime::component::Linker.