feat: package bt as npm pkg

.github/workflows/release.yml

@@ -488,3 +488,64 @@ jobs:
           & $btExe --version
           $env:PATH = "$binDir;$env:PATH"
           & $btExe self update --check --channel stable
+
+  publish-npm:
+    needs:
+      - plan
+      - announce
+    if: ${{ needs.announce.result == 'success' }}
+    runs-on: ubuntu-22.04
+    environment: release
+    env:
+      GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+    steps:
+      - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
+        with:
+          persist-credentials: false
+
+      - name: Download release archives
+        env:
+          TAG: ${{ needs.plan.outputs.tag }}
+        shell: bash
+        run: |
+          set -euo pipefail
+          mkdir -p archives
+          gh release download "$TAG" \
+            --repo "${{ github.repository }}" \
+            --pattern 'bt-*.tar.gz' \
+            --pattern 'bt-*.zip' \
+            --dir archives
+          ls -la archives
+
+      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
+        with:
+          node-version: "20"
+          registry-url: "https://registry.npmjs.org"
+
+      - name: Build npm packages
+        run: |
+          node npm/scripts/build-platform-packages.mjs \
+            --version "${{ needs.plan.outputs.release-version }}" \
+            --archives-dir archives \
+            --out-dir npm/dist
+
+      - name: Publish platform packages
+        env:
+          NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
+        shell: bash
+        run: |
+          set -euo pipefail
+          shopt -s nullglob
+          for dir in npm/dist/bt-*; do
+            name="$(node -p "require('./$dir/package.json').name")"
+            version="$(node -p "require('./$dir/package.json').version")"
+            # Skip already-published versions so a partial publish can be re-run.
+            # Test output, not exit code: npm view is empty for a missing version.
+            published="$(npm view "$name@$version" version 2>/dev/null || true)"
+            if [ -n "$published" ]; then
+              echo "Skipping $name@$version (already published)"
+              continue
+            fi
+            echo "Publishing $name@$version"
+            (cd "$dir" && npm publish --access public --provenance)
+          done

npm/scripts/build-platform-packages.mjs

@@ -0,0 +1,146 @@
+#!/usr/bin/env node
+// Builds the per-platform npm packages from cargo-dist release archives.
+//
+//   --version <semver>      version to stamp into every package.json (required)
+//   --archives-dir <path>   directory containing cargo-dist archives
+//                           (bt-<target>.tar.gz / bt-<target>.zip), required
+//   --out-dir <path>        directory to write packages into (default: npm/dist)
+//
+// Emits <out-dir>/bt-<pkg>/ (one per target), each ready to `npm publish`.
+// The `bt` command is exposed via the `braintrust` SDK, which lists these
+// packages as optionalDependencies and ships a launcher that resolves the
+// matching binary.
+
+import { execFileSync } from "node:child_process";
+import {
+  chmodSync,
+  cpSync,
+  existsSync,
+  mkdirSync,
+  readFileSync,
+  readdirSync,
+  rmSync,
+  statSync,
+  writeFileSync,
+} from "node:fs";
+import { dirname, join, resolve } from "node:path";
+import { fileURLToPath } from "node:url";
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const NPM_DIR = resolve(__dirname, "..");
+
+function parseArgs(argv) {
+  const args = {};
+  for (let i = 0; i < argv.length; i++) {
+    const k = argv[i];
+    if (k.startsWith("--")) args[k.slice(2)] = argv[++i];
+  }
+  return args;
+}
+
+const args = parseArgs(process.argv.slice(2));
+const version = args.version;
+const archivesDir = args["archives-dir"] && resolve(args["archives-dir"]);
+const outDir = resolve(args["out-dir"] ?? join(NPM_DIR, "dist"));
+
+if (!version) throw new Error("--version is required");
+if (!archivesDir) throw new Error("--archives-dir is required");
+if (!existsSync(archivesDir))
+  throw new Error(`archives-dir not found: ${archivesDir}`);
+
+const targets = JSON.parse(readFileSync(join(NPM_DIR, "targets.json"), "utf8"));
+
+if (existsSync(outDir)) rmSync(outDir, { recursive: true, force: true });
+mkdirSync(outDir, { recursive: true });
+
+function extract(archive, dest) {
+  mkdirSync(dest, { recursive: true });
+  if (archive.endsWith(".tar.gz")) {
+    execFileSync("tar", ["-xzf", archive, "-C", dest], { stdio: "inherit" });
+  } else if (archive.endsWith(".zip")) {
+    execFileSync("unzip", ["-o", "-q", archive, "-d", dest], {
+      stdio: "inherit",
+    });
+  } else {
+    throw new Error(`Unsupported archive: ${archive}`);
+  }
+}
+
+function findBinary(rootDir, binName) {
+  const stack = [rootDir];
+  while (stack.length) {
+    const cur = stack.pop();
+    for (const entry of readdirSync(cur)) {
+      const full = join(cur, entry);
+      const s = statSync(full);
+      if (s.isDirectory()) stack.push(full);
+      else if (entry === binName) return full;
+    }
+  }
+  throw new Error(`Binary ${binName} not found under ${rootDir}`);
+}
+
+// --- Per-platform packages ---
+let built = 0;
+for (const [target, spec] of Object.entries(targets)) {
+  const archiveName = `bt-${target}.${spec.archiveExt}`;
+  const archive = join(archivesDir, archiveName);
+  if (!existsSync(archive)) {
+    // Fail hard, don't skip: the SDK pins each package at an exact version, so a
+    // missing platform would break installs for that platform at runtime.
+    throw new Error(`Archive not found for ${target}: ${archive}`);
+  }
+
+  const stagingDir = join(outDir, ".staging", target);
+  extract(archive, stagingDir);
+  const binPath = findBinary(stagingDir, spec.bin);
+
+  const pkgName = `@braintrust/bt-${spec.pkg}`;
+  const pkgOut = join(outDir, `bt-${spec.pkg}`);
+  const pkgBin = join(pkgOut, "bin");
+  mkdirSync(pkgBin, { recursive: true });
+  cpSync(binPath, join(pkgBin, spec.bin));
+  if (spec.os !== "win32") chmodSync(join(pkgBin, spec.bin), 0o755);
+
+  const platformPkg = {
+    name: pkgName,
+    version,
+    description: `Prebuilt bt binary for ${spec.os}-${spec.cpu}${spec.libc ? `-${spec.libc}` : ""}`,
+    homepage: "https://github.com/braintrustdata/bt",
+    repository: {
+      type: "git",
+      url: "git+https://github.com/braintrustdata/bt.git",
+    },
+    license: "Apache-2.0",
+    author: "Braintrust engineering <eng@braintrust.dev>",
+    files: ["bin/"],
+    os: [spec.os],
+    cpu: [spec.cpu],
+    publishConfig: {
+      access: "public",
+      provenance: true,
+    },
+    preferUnplugged: true,
+  };
+  if (spec.libc) platformPkg.libc = [spec.libc];
+
+  writeFileSync(
+    join(pkgOut, "package.json"),
+    JSON.stringify(platformPkg, null, 2) + "\n",
+  );
+  writeFileSync(
+    join(pkgOut, "README.md"),
+    `# ${pkgName}\n\nPrebuilt \`bt\` binary for ${spec.os}-${spec.cpu}${spec.libc ? ` (${spec.libc})` : ""}.\n\nInstalled automatically as an optional dependency of [\`braintrust\`](https://www.npmjs.com/package/braintrust), which exposes the \`bt\` command. Install that package instead.\n`,
+  );
+
+  console.log(`Built ${pkgName} -> ${pkgOut}`);
+  built++;
+}
+
+rmSync(join(outDir, ".staging"), { recursive: true, force: true });
+
+const expected = Object.keys(targets).length;
+if (built !== expected) {
+  throw new Error(`Built ${built} packages but expected ${expected}`);
+}
+console.log(`\nAll ${built} packages written to ${outDir}`);

npm/targets.json

@@ -0,0 +1,54 @@
+{
+  "aarch64-apple-darwin": {
+    "pkg": "darwin-arm64",
+    "os": "darwin",
+    "cpu": "arm64",
+    "bin": "bt",
+    "archiveExt": "tar.gz"
+  },
+  "x86_64-apple-darwin": {
+    "pkg": "darwin-x64",
+    "os": "darwin",
+    "cpu": "x64",
+    "bin": "bt",
+    "archiveExt": "tar.gz"
+  },
+  "aarch64-unknown-linux-gnu": {
+    "pkg": "linux-arm64",
+    "os": "linux",
+    "cpu": "arm64",
+    "libc": "glibc",
+    "bin": "bt",
+    "archiveExt": "tar.gz"
+  },
+  "x86_64-unknown-linux-gnu": {
+    "pkg": "linux-x64",
+    "os": "linux",
+    "cpu": "x64",
+    "libc": "glibc",
+    "bin": "bt",
+    "archiveExt": "tar.gz"
+  },
+  "x86_64-unknown-linux-musl": {
+    "pkg": "linux-x64-musl",
+    "os": "linux",
+    "cpu": "x64",
+    "libc": "musl",
+    "bin": "bt",
+    "archiveExt": "tar.gz"
+  },
+  "aarch64-pc-windows-msvc": {
+    "pkg": "win32-arm64",
+    "os": "win32",
+    "cpu": "arm64",
+    "bin": "bt.exe",
+    "archiveExt": "zip"
+  },
+  "x86_64-pc-windows-msvc": {
+    "pkg": "win32-x64",
+    "os": "win32",
+    "cpu": "x64",
+    "bin": "bt.exe",
+    "archiveExt": "zip"
+  }
+}