Show the build's commit in the page footer

Workers can't shell out at request time, so the commit has to be baked
in before wrangler bundles the sources. compile-views.ts grows a second
job and becomes scripts/build.ts: alongside the precompiled views it
writes src/commit.generated.ts with `git describe --tags --always
--dirty`, which yields a bare short hash until the repo is tagged and
marks builds made from an unclean working copy.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

1 files changed, 52 insertions, 0 deletions

diff --git a/scripts/build.ts b/scripts/build.ts
new file mode 100644
index 0000000..766e5e8
--- /dev/null
+++ b/scripts/build.ts
@@ -0,0 +1,52 @@
+// Generates the sources that can't exist at runtime on Workers:
+//
+//   src/views.generated.ts  - views/*.eta precompiled into plain functions.
+//     Workers disallow runtime code generation (`new Function`), so Eta cannot
+//     compile templates there at request time.
+//   src/commit.generated.ts - the commit this build was made from, for the
+//     page footer. Workers can't shell out to git at request time either.
+import { execFileSync } from "node:child_process";
+import { Eta } from "eta";
+import fs from "node:fs";
+import path from "node:path";
+
+const root = path.join(import.meta.dirname, "..");
+const viewsDir = path.join(root, "views");
+const eta = new Eta({ views: viewsDir });
+
+const names = fs
+  .readdirSync(viewsDir)
+  .filter((name) => name.endsWith(".eta"))
+  .sort();
+
+let out = `// @ts-nocheck
+// Generated by scripts/build.ts -- do not edit.
+export const views = {
+`;
+for (const name of names) {
+  const source = fs.readFileSync(path.join(viewsDir, name), "utf8");
+  const body = eta.compileToString(source);
+  out += `  ${JSON.stringify(name)}: function (it, options) {\n${body}\n  },\n`;
+}
+out += "};\n";
+
+fs.writeFileSync(path.join(root, "src", "views.generated.ts"), out);
+console.log(`Compiled ${names.length} templates to src/views.generated.ts`);
+
+// Untagged repositories describe as a bare short hash; --dirty marks a build
+// made from an unclean working copy.
+let commit = "unknown";
+try {
+  commit = execFileSync("git", ["describe", "--tags", "--always", "--dirty"], {
+    cwd: root,
+    encoding: "utf8",
+  }).trim();
+} catch {
+  // Building from a source copy without git history.
+}
+
+fs.writeFileSync(
+  path.join(root, "src", "commit.generated.ts"),
+  `// Generated by scripts/build.ts -- do not edit.\nexport const commit = ${JSON.stringify(commit)};\n`,
+);
+console.log(`Wrote commit ${commit} to src/commit.generated.ts`);