fix: persist OG image cache outside act runner workspace

The cache was written to .cache/og/ relative to the workspace, which is
under /usr/local/git/.cache/act/<unique-hash>/hostexecutor/ — a new path
per run, so every build regenerated all images from scratch.

OG_CACHE_DIR env var now controls the cache path (resolved to an absolute
path). CI sets it to /usr/local/git/.cache/og, which survives between runs.
Locally it still defaults to .cache/og inside the project dir.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.github/workflows/deploy.yml

@@ -125,6 +125,7 @@ jobs:
           GITEA_URL: https://gitea.giersig.eu
           GITEA_INTERNAL_URL: http://127.0.0.1:3000
           GITEA_ORG: giersig.eu
+          OG_CACHE_DIR: /usr/local/git/.cache/og
 
       - name: Deploy via rsync
         run: |

eleventy.config.js

@@ -26,6 +26,12 @@ const postGraph = esmRequire("@rknightuk/eleventy-plugin-post-graph");
 const __dirname = dirname(fileURLToPath(import.meta.url));
 const siteUrl = process.env.SITE_URL || "https://example.com";
 
+// OG image cache — persistent across CI runs when OG_CACHE_DIR env var is set.
+// In CI, point this outside the act runner workspace (e.g. /usr/local/git/.cache/og).
+const OG_CACHE_DIR = process.env.OG_CACHE_DIR
+  ? resolve(process.env.OG_CACHE_DIR)
+  : resolve(__dirname, ".cache", "og");
+
 // Slugify each path segment, preserving "/" separators for nested tags (e.g. "tech/programming")
 const nestedSlugify = (str) => {
   if (!str) return "";
@@ -49,7 +55,7 @@ export default function (eleventyConfig) {
   eleventyConfig.setUseGitIgnore(false);
 
   // Passthrough copy for OG images
-  eleventyConfig.addPassthroughCopy({ ".cache/og": "images/og" });
+  eleventyConfig.addPassthroughCopy({ [OG_CACHE_DIR]: "images/og" });
 
   // Ignore output directory (prevents re-processing generated files via symlink)
   eleventyConfig.ignores.add("_site");
@@ -78,8 +84,8 @@ export default function (eleventyConfig) {
   eleventyConfig.watchIgnores.add("/app/data/site/**");
   eleventyConfig.watchIgnores.add("pagefind");
   eleventyConfig.watchIgnores.add("pagefind/**");
-  eleventyConfig.watchIgnores.add(".cache/og");
-  eleventyConfig.watchIgnores.add(".cache/og/**");
+  eleventyConfig.watchIgnores.add(OG_CACHE_DIR);
+  eleventyConfig.watchIgnores.add(OG_CACHE_DIR + "/**");
   eleventyConfig.watchIgnores.add(".cache/unfurl");
   eleventyConfig.watchIgnores.add(".cache/unfurl/**");
 
@@ -388,9 +394,8 @@ export default function (eleventyConfig) {
   eleventyConfig.on("eleventy.before", () => { _ogFileSet = null; });
   function hasOgImage(ogSlug) {
     if (!_ogFileSet) {
-      const ogDir = resolve(__dirname, ".cache", "og");
       try {
-        _ogFileSet = new Set(readdirSync(ogDir));
+        _ogFileSet = new Set(readdirSync(OG_CACHE_DIR));
       } catch {
         _ogFileSet = new Set();
       }
@@ -658,7 +663,7 @@ export default function (eleventyConfig) {
   eleventyConfig.addPassthroughCopy("favicon.ico");
   eleventyConfig.addPassthroughCopy("robots.txt");
   eleventyConfig.addPassthroughCopy("interactive");
-  eleventyConfig.addPassthroughCopy({ ".cache/og": "og" });
+  eleventyConfig.addPassthroughCopy({ [OG_CACHE_DIR]: "og" });
   // Funkwhale images are copied in eleventy.after (after data files download them)
 
   // Copy vendor web components from node_modules
@@ -929,8 +934,7 @@ export default function (eleventyConfig) {
   // Check if a generated OG image exists for this slug
   eleventyConfig.addFilter("hasOgImage", (slug) => {
     if (!slug) return false;
-    const ogPath = resolve(__dirname, ".cache", "og", `${slug}.png`);
-    return existsSync(ogPath);
+    return existsSync(resolve(OG_CACHE_DIR, `${slug}.png`));
   });
 
   // Inline file contents (for critical CSS inlining)
@@ -1589,7 +1593,6 @@ export default function (eleventyConfig) {
   eleventyConfig.on("eleventy.before", () => {
     console.time("[og] image generation");
     const contentDir = resolve(__dirname, "content");
-    const cacheDir = resolve(__dirname, ".cache");
     const siteName = process.env.SITE_NAME || "My IndieWeb Blog";
     const BATCH_SIZE = 100;
     try {
@@ -1601,7 +1604,7 @@ export default function (eleventyConfig) {
             "--expose-gc",
             resolve(__dirname, "lib", "og-cli.js"),
             contentDir,
-            cacheDir,
+            OG_CACHE_DIR,
             siteName,
             String(BATCH_SIZE),
           ], {
@@ -1620,16 +1623,15 @@ export default function (eleventyConfig) {
       }
 
       // Sync new OG images to output directory.
-      // During incremental builds, .cache/og is in watchIgnores so Eleventy's
+      // During incremental builds, OG_CACHE_DIR is in watchIgnores so Eleventy's
       // passthrough copy won't pick up newly generated images. Copy them manually.
-      const ogCacheDir = resolve(cacheDir, "og");
       const ogOutputDir = resolve(__dirname, "_site", "og");
-      if (existsSync(ogCacheDir) && existsSync(resolve(__dirname, "_site"))) {
+      if (existsSync(OG_CACHE_DIR) && existsSync(resolve(__dirname, "_site"))) {
         mkdirSync(ogOutputDir, { recursive: true });
         let synced = 0;
-        for (const file of readdirSync(ogCacheDir)) {
+        for (const file of readdirSync(OG_CACHE_DIR)) {
           if (file.endsWith(".png") && !existsSync(resolve(ogOutputDir, file))) {
-            copyFileSync(resolve(ogCacheDir, file), resolve(ogOutputDir, file));
+            copyFileSync(resolve(OG_CACHE_DIR, file), resolve(ogOutputDir, file));
             synced++;
           }
         }

lib/og-cli.js

@@ -4,7 +4,7 @@
  * CLI entry point for OG image generation.
  * Runs as a separate process to isolate memory from Eleventy.
  *
- * Usage: node lib/og-cli.js <contentDir> <cacheDir> <siteName> [batchSize]
+ * Usage: node lib/og-cli.js <contentDir> <ogDir> <siteName> [batchSize]
  *
  * batchSize: Max images to generate per invocation (0 = unlimited).
  *            When set, exits after generating that many images so the caller
@@ -14,15 +14,15 @@
 
 import { generateOgImages } from "./og.js";
 
-const [contentDir, cacheDir, siteName, batchSizeStr] = process.argv.slice(2);
+const [contentDir, ogDir, siteName, batchSizeStr] = process.argv.slice(2);
 
-if (!contentDir || !cacheDir || !siteName) {
-  console.error("[og] Usage: node og-cli.js <contentDir> <cacheDir> <siteName> [batchSize]");
+if (!contentDir || !ogDir || !siteName) {
+  console.error("[og] Usage: node og-cli.js <contentDir> <ogDir> <siteName> [batchSize]");
   process.exit(1);
 }
 
 const batchSize = parseInt(batchSizeStr, 10) || 0;
-const result = await generateOgImages(contentDir, cacheDir, siteName, batchSize);
+const result = await generateOgImages(contentDir, ogDir, siteName, batchSize);
 
 // Exit code 2 signals "batch complete, more images remain"
 if (result?.hasMore) {

lib/og.js

@@ -426,8 +426,7 @@ function scanContentFiles(contentDir) {
  * @param {number} batchSize - Max images to generate (0 = unlimited)
  * @returns {{ hasMore: boolean }} Whether more images need generation
  */
-export async function generateOgImages(contentDir, cacheDir, siteName, batchSize = 0) {
-  const ogDir = join(cacheDir, "og");
+export async function generateOgImages(contentDir, ogDir, siteName, batchSize = 0) {
   mkdirSync(ogDir, { recursive: true });
 
   const manifestPath = join(ogDir, "manifest.json");