2.21.2. WasmPlugin container format
Istio supports Open Container Initiative (OCI) images in its Wasm Plugin mechanism. You can distribute your Wasm Plugins as a container image, and you can use the spec.url field to refer to a container registry location. For example, quay.io/my-username/my-plugin:latest.
Because each execution environment (runtime) for a WASM module can have runtime-specific configuration parameters, a WASM image can be composed of two layers:
-
plugin.wasm (Required) - Content layer. This layer consists of a
.wasmbinary containing the bytecode of your WebAssembly module, to be loaded by the runtime. You must name this fileplugin.wasm. - runtime-config.json (Optional) - Configuration layer. This layer consists of a JSON-formatted string that describes metadata about the module for the target runtime. The config layer might also contain additional data, depending on the target runtime. For example, the config for a WASM Envoy Filter contains root_ids available on the filter.