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Version: 1.x

WAsmcloud SHell (wash) plugin

Starting from version 0.28 of the WAsmcloud SHell (wash), plugins written in WebAssembly can be used to extend wash with new functionality.

This folder contains an example WebAssembly plugin for wash that you can use as a starting point for your own projects.

Prerequisites​

  • cargo >=1.75
  • wash >=0.28.1

Building​

You can build your plugin using either cargo or wash:

console
wash build

Your component will be built, signed and placed in the build folder.

You can inspect your component with wash inspect:

console
wash inspect ./build/http_blobstore_s.wasm

$ wash inspect build/wash_plugin_rust_s.wasm


                        wash-plugin-rust - Component
  Account         AB7WCKG4XTUEN524UIQIV7SHUG4G3HH6FXHPZZTZVWJDXWUPH4IX2NL4
  Component       MA6Y3RQ5UYKQSPGNNMTR4QEJSORMAW2WRUX4QB5BPJIUXOIFSSWFS4U7
  Expires                                                            never
  Can Be Used                                                  immediately
  Version                                                        0.1.0 (0)
  Embedded WIT                                                        true
                                    Tags
  wasmcloud.com/experimental

You can also use cargo to build your component:

console
cargo build

[!WARNING] Since this project represents a WebAssembly component, cargo build must be used with a WebAssembly friendly target. This works without specifying --target to cargodue to the settings in .cargo/config.toml.

wash is recommended for building this component -- cargo does not sign your WebAssembly component or take into account settings in wasmcloud.toml.

Using your new plugin from wasmCloud​

![NOTE] Consider reading the documentation for wash plugins

1. Install your newly built plugin with wash​

wash plugins are stored on disk at a location you choose (by specifying WASH_PLUGIN_DIR) -- by default it is ~/.wash/plugins.

You can use the wash install subcommand to install your newly built plugin:

console
wash plugin install build/wash_plugin_rust_s.wasm

Alternatively, you can copy the WebAssembly binary into WASH PLUGIN_DIR manually.

You can confirm your plugin is installed with wash plugin list:

➜ wash plugin list


  Name           ID      Version   Author      Description
  Hello Plugin   hello   0.1.0     WasmCloud   A simple plugin that says hello and logs a bunch of things

2. Use your new plugin with wash​

Plugins are accessible as top level subcommands -- given a plugin with the ID hello you can call wash hello to trigger it.

By default the example plugin in this folder has some required args, so a complete call would look like this:

console
wash hello --foo . wasmcloud.toml