chore: Add SDK metadata field to the wasm file generated from the @fastly-js-compute cli

Author: Jake Champion

js-compute-runtime-cli.js

@@ -3,6 +3,7 @@
 import { parseInputs } from './src/parseInputs.js'
 import { printVersion } from "./src/printVersion.js";
 import { printHelp } from "./src/printHelp.js";
+import { addSdkMetadataField } from "./src/addSdkMetadataField.js";
 
 const {wasmEngine, input, component, output, version, help} = await parseInputs(process.argv.slice(2))
 
@@ -23,4 +24,5 @@ if (version) {
     const {compileComponent} = await import('./src/component.js');
     await compileComponent(output);
   }
+  await addSdkMetadataField(output);
 }

src/addSdkMetadataField.js

@@ -0,0 +1,23 @@
+import { metadataAdd } from '@bytecodealliance/jco';
+import { readFile, writeFile } from 'node:fs/promises';
+import { dirname, join } from "node:path";
+import { fileURLToPath } from "node:url";
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+export async function addSdkMetadataField(wasmPath) {
+  const packageJson = await readFile(join(__dirname, "../package.json"), {
+    encoding: "utf-8",
+  });
+  const { name, version } = JSON.parse(packageJson);
+  const metadata = [
+    [
+      "sdk", 
+      [
+        [name, version],
+      ],
+    ],
+  ];
+  const wasm = await readFile(wasmPath);
+  const newWasm = await metadataAdd(wasm, metadata);
+  await writeFile(wasmPath, newWasm);
+}