Add changesets based publishing

.github/scripts/has-unpublished-packages.mjs

@@ -0,0 +1,53 @@
+import { appendFileSync } from "node:fs";
+import { readFile } from "node:fs/promises";
+
+async function hasPublishedVersion(pkg) {
+  const response = await fetch(
+    `https://registry.npmjs.org/${encodeURIComponent(pkg.name)}`,
+    { headers: { accept: "application/vnd.npm.install-v1+json" } },
+  );
+
+  if (response.status === 404) {
+    return false;
+  }
+
+  if (!response.ok) {
+    throw new Error(
+      `Failed to query ${pkg.name}: ${response.status} ${response.statusText}`,
+    );
+  }
+
+  const metadata = await response.json();
+  return Object.prototype.hasOwnProperty.call(
+    metadata.versions ?? {},
+    pkg.version,
+  );
+}
+
+async function main() {
+  const pkg = JSON.parse(await readFile("package.json", "utf8"));
+  const isPublished = await hasPublishedVersion(pkg);
+
+  if (isPublished) {
+    console.log(`${pkg.name}@${pkg.version} is already published`);
+  } else {
+    console.log(`${pkg.name}@${pkg.version} is not published yet`);
+  }
+
+  const shouldPublish = !isPublished;
+  const output = [
+    `has_unpublished=${String(shouldPublish)}`,
+    `should_publish=${String(shouldPublish)}`,
+  ].join("\n") + "\n";
+
+  if (process.env.GITHUB_OUTPUT) {
+    appendFileSync(process.env.GITHUB_OUTPUT, output);
+  } else {
+    process.stdout.write(output);
+  }
+}
+
+main().catch(error => {
+  console.error(error);
+  process.exit(1);
+});

.github/workflows/release.yml

@@ -45,21 +45,10 @@ jobs:
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
-      - name: Check whether this version still needs publishing
+      - name: Check for unpublished package versions
         if: steps.changesets.outputs.hasChangesets == 'false'
         id: publish-check
-        shell: bash
-        run: |
-          PACKAGE_NAME=$(node -p "require('./package.json').name")
-          PACKAGE_VERSION=$(node -p "require('./package.json').version")
-
-          echo "Checking whether ${PACKAGE_NAME}@${PACKAGE_VERSION} is already on npm"
-          if npm view "${PACKAGE_NAME}@${PACKAGE_VERSION}" version >/dev/null 2>&1; then
-            echo "should_publish=false" >> "$GITHUB_OUTPUT"
-            exit 0
-          fi
-
-          echo "should_publish=true" >> "$GITHUB_OUTPUT"
+        run: node .github/scripts/has-unpublished-packages.mjs
 
   publish:
     name: Publish