feat: optimize asset delivery with build-time compression and encoding negotiation

2026-02-01 00:23:40 -06:00 · 2026-01-29 13:56:10 -06:00
parent e008ee5a12
commit 4deeef2f00
12 changed files with 634 additions and 143 deletions
@@ -0,0 +1,148 @@
+#!/usr/bin/env bun
+/**
+ * Pre-compress static assets with maximum compression levels.
+ * Run after `bun run build`.
+ *
+ * Generates .gz, .br, .zst variants for compressible files ≥ MIN_SIZE bytes.
+ * These are embedded alongside originals by rust-embed and served via
+ * content negotiation in src/web/assets.rs.
+ */
+import { readdir, stat, readFile, writeFile } from "fs/promises";
+import { join, extname } from "path";
+import { gzipSync, brotliCompressSync, constants } from "zlib";
+import { $ } from "bun";
+
+// Must match COMPRESSION_MIN_SIZE in src/web/encoding.rs
+const MIN_SIZE = 512;
+
+const COMPRESSIBLE_EXTENSIONS = new Set([
+  ".js",
+  ".css",
+  ".html",
+  ".json",
+  ".svg",
+  ".txt",
+  ".xml",
+  ".map",
+]);
+
+// Check if zstd CLI is available
+let hasZstd = false;
+try {
+  await $`which zstd`.quiet();
+  hasZstd = true;
+} catch {
+  console.warn("Warning: zstd not found, skipping .zst generation");
+}
+
+async function* walkDir(dir: string): AsyncGenerator<string> {
+  try {
+    const entries = await readdir(dir, { withFileTypes: true });
+    for (const entry of entries) {
+      const path = join(dir, entry.name);
+      if (entry.isDirectory()) {
+        yield* walkDir(path);
+      } else if (entry.isFile()) {
+        yield path;
+      }
+    }
+  } catch {
+    // Directory doesn't exist, skip
+  }
+}
+
+async function compressFile(path: string): Promise<void> {
+  const ext = extname(path);
+
+  if (!COMPRESSIBLE_EXTENSIONS.has(ext)) return;
+  if (path.endsWith(".br") || path.endsWith(".gz") || path.endsWith(".zst")) return;
+
+  const stats = await stat(path);
+  if (stats.size < MIN_SIZE) return;
+
+  // Skip if all compressed variants already exist
+  const variantsExist = await Promise.all([
+    stat(`${path}.br`).then(
+      () => true,
+      () => false
+    ),
+    stat(`${path}.gz`).then(
+      () => true,
+      () => false
+    ),
+    hasZstd
+      ? stat(`${path}.zst`).then(
+          () => true,
+          () => false
+        )
+      : Promise.resolve(false),
+  ]);
+
+  if (variantsExist.every((exists) => exists || !hasZstd)) {
+    return;
+  }
+
+  const content = await readFile(path);
+  const originalSize = content.length;
+
+  // Brotli (maximum quality = 11)
+  const brContent = brotliCompressSync(content, {
+    params: {
+      [constants.BROTLI_PARAM_QUALITY]: 11,
+    },
+  });
+  await writeFile(`${path}.br`, brContent);
+
+  // Gzip (level 9)
+  const gzContent = gzipSync(content, { level: 9 });
+  await writeFile(`${path}.gz`, gzContent);
+
+  // Zstd (level 19 - maximum)
+  if (hasZstd) {
+    try {
+      await $`zstd -19 -q -f -o ${path}.zst ${path}`.quiet();
+    } catch (e) {
+      console.warn(`Warning: Failed to compress ${path} with zstd: ${e}`);
+    }
+  }
+
+  const brRatio = ((brContent.length / originalSize) * 100).toFixed(1);
+  const gzRatio = ((gzContent.length / originalSize) * 100).toFixed(1);
+  console.log(`Compressed: ${path} (br: ${brRatio}%, gz: ${gzRatio}%, ${originalSize} bytes)`);
+}
+
+async function main() {
+  console.log("Pre-compressing static assets...");
+
+  // Banner uses adapter-static with output in dist/
+  const dirs = ["dist"];
+  let scannedFiles = 0;
+  let compressedFiles = 0;
+
+  for (const dir of dirs) {
+    for await (const file of walkDir(dir)) {
+      const ext = extname(file);
+      scannedFiles++;
+
+      if (
+        COMPRESSIBLE_EXTENSIONS.has(ext) &&
+        !file.endsWith(".br") &&
+        !file.endsWith(".gz") &&
+        !file.endsWith(".zst")
+      ) {
+        const stats = await stat(file);
+        if (stats.size >= MIN_SIZE) {
+          await compressFile(file);
+          compressedFiles++;
+        }
+      }
+    }
+  }
+
+  console.log(`Done! Scanned ${scannedFiles} files, compressed ${compressedFiles} files.`);
+}
+
+main().catch((e) => {
+  console.error("Compression failed:", e);
+  process.exit(1);
+});