morphir extension runtimes

morphir extension runtimes

Reports the extension runtimes of the host you run. Today there is one, wasm: the runtime that runs WASM extension modules. The report says whether it is available in this executable, which engine runs the modules, which profiles the host runs and which bounds it enforces. When the runtime is unavailable, the report gives the reason.

Synopsis

morphir extension runtimes [--json]
dotnet-morphir extension runtimes [--json]

Options:

• --json: Write one JSON document on stdout.

Description

The command loads no module. It asks the executable you run, not its file name or its install folder, so a copy of morphir that lost its engine library reports that copy’s state.

The host checks the engine only when something needs it: this command, or a command that runs a WASM module. It checks once per process. Starting morphir, --version, --help, extension list with only built-in extensions, and every other command that needs no WASM never load the engine. A missing or broken engine therefore cannot break them.

The command exits with 0 whether the runtime is available or not: the report is the result. Logs and diagnostics go to stderr, so morphir extension runtimes --json | jq works.

Output

An available runtime:

$ morphir extension runtimes
Host: morphir
Platform: win-arm64
wasm: available
  Engine: wasmtime 50.0.1
  Profiles: extism-kernel-v1
  Bounds: memory ceiling 268435456 bytes (256 MiB), call deadline enforced, instruction budget enforced

{
  "host": "morphir",
  "platform": "win-arm64",
  "runtimes": [
    {
      "kind": "wasm",
      "available": true,
      "engine": { "name": "wasmtime", "version": "50.0.1" },
      "profiles": ["extism-kernel-v1"],
      "bounds": { "memoryBytes": 268435456, "deadline": "enforced", "budget": "enforced" }
    }
  ]
}

An unavailable runtime, here a dotnet-morphir whose engine library is not in its folder:

$ dotnet-morphir extension runtimes
Host: dotnet-morphir
Platform: win-arm64
wasm: unavailable (engine_missing)
  Engine: wasmtime 50.0.1
  Reason: the engine's native library is not in this installation

{
  "host": "dotnet-morphir",
  "platform": "win-arm64",
  "runtimes": [
    {
      "kind": "wasm",
      "available": false,
      "reason": "engine_missing",
      "engine": { "name": "wasmtime", "version": "50.0.1" }
    }
  ]
}

The report has no member for the deployment offering (native-aot, self-contained, framework-dependent or dotnet-tool). The host identity now records named release profiles, but this report has not yet added those fields. It does not guess a deployment from the file name or path. A runner that needs the offering is given it as an input.

Reasons

No configuration or environment setting enables WASM on Windows x64. CET, context validation, signal-based traps and Spectre mitigations retain their defaults. No other command loads the engine.

The host decides the reason the first time something needs the engine: this report, loading a module, or listing a WASM extension. --version, --help and the worker’s argument and build-identity checks never load it.

Commands that need the runtime

A command that needs the WASM runtime in a host without it fails with extension.runtime_unavailable before it reads the module, and names the host, the platform and the reason. It never shows a native library loading error. Today the only such command is the internal morphir extension worker. It checks its arguments, then the build identity, then the engine, then the module, and reports the first that fails. Without a usable engine it writes one refused event with the code extension.runtime_unavailable on stderr, nothing on stdout, and exits with 3:

{"profile":"morphir/command-event","contractVersion":"0.1.0","command":"extension worker","sequence":1,"event":"refused","error":{"code":"extension.runtime_unavailable","message":"The WASM module of extension 'python' at '/work/python.wasm' cannot be loaded with extension.runtime_unavailable: the WASM runtime of dotnet-morphir 0.4.0 on linux-musl-x64 is unavailable (platform_unsupported): the engine has no build for this platform."}}

In extension list, a wasm extension has available set to false in a host whose runtime is unavailable, and built-in extensions stay available. See extension list.

See also

• morphir extension list
• morphir extension worker (experimental and internal)