marky

commit 5563d32bc82884394ef7bfff647d21d632a6f178
parent ec9b947472ab9436481f43599a924b110e2ba5f5
Author: David Eisinger <[email protected]>
Date:   Thu,  9 Oct 2025 14:32:36 -0400

Cache busting

Diffstat:
M
internal/api.go
 | 
2
++
M
internal/static.go
 | 
40
++++++++++++++++++++++++++++++++++++++++

2 files changed, 42 insertions(+), 0 deletions(-)
diff --git a/internal/api.go b/internal/api.go
@@ -362,6 +362,7 @@ func NewHandlerWithConfig(db *DB, cfg HandlerConfig) (http.Handler, error) {
                         html = out
                     }
                 }
+                html = applyCacheBust(html)
                 w.Header().Set("Content-Type", "text/html; charset=utf-8")
                 _, _ = w.Write(html)
                 return
@@ -441,6 +442,7 @@ func NewHandlerWithConfig(db *DB, cfg HandlerConfig) (http.Handler, error) {
                                 }
                             }
                         }
+                        html = applyCacheBust(html)
                         w.Header().Set("Content-Type", "text/html; charset=utf-8")
                         _, _ = w.Write(html)
                         return
diff --git a/internal/static.go b/internal/static.go
@@ -3,6 +3,8 @@ package internal
 import (
     "bytes"
     "embed"
+    "crypto/sha256"
+    "fmt"
     "io/fs"
     "net/http"
     "path"
@@ -46,6 +48,8 @@ func StaticHandlerWithConfig(cfg HandlerConfig) (http.Handler, error) {
             indexBytes = nb
         }
     }
+    // Apply cache-busting query params to static asset URLs
+    indexBytes = applyCacheBust(indexBytes)
     return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
         p := strings.TrimPrefix(r.URL.Path, "/")
         if p == "" {
@@ -94,3 +98,39 @@ func RenderPage(name string, cfg HandlerConfig) ([]byte, error) {
     }
     return pageBytes, nil
 }
+
+// applyCacheBust appends a short content hash to known asset URLs in HTML,
+// e.g., /app.js?v=abcd1234. This helps CDNs like Cloudflare pick up changes
+// without manual purges.
+func applyCacheBust(html []byte) []byte {
+    sub, err := fs.Sub(webAssets, "web")
+    if err != nil { return html }
+    // Build fingerprint map for assets we serve locally
+    assets := []string{
+        "app.js",
+        "styles.css",
+        "vendor/vue.global.prod.js",
+        "vendor/marked.min.js",
+        "vendor/purify.min.js",
+    }
+    bust := map[string]string{}
+    for _, p := range assets {
+        if b, err := fs.ReadFile(sub, p); err == nil {
+            sum := sha256.Sum256(b)
+            bust[p] = fmt.Sprintf("%x", sum)[:10]
+        }
+    }
+    // Replace src/href occurrences
+    out := html
+    for p, v := range bust {
+        // src="/path"
+        from := []byte("src=\"/"+p+"\"")
+        to := []byte("src=\"/"+p+"?v="+v+"\"")
+        out = bytes.ReplaceAll(out, from, to)
+        // href="/path"
+        fromH := []byte("href=\"/"+p+"\"")
+        toH := []byte("href=\"/"+p+"?v="+v+"\"")
+        out = bytes.ReplaceAll(out, fromH, toH)
+    }
+    return out
+}