优化

internal/service/image_proxy_upstream.go

@@ -0,0 +1,63 @@
+package service
+
+import (
+	"net/url"
+	"strconv"
+	"strings"
+)
+
+// imageCacheKeyURL normalizes an upstream image URL before it is hashed into a
+// disk cache key. Credential query parameters are dropped: a remote Emby token
+// is per-account, so removing it cannot make two different images collide, but
+// it stops a token rotation from invalidating every cached poster at once.
+func imageCacheKeyURL(raw string) string {
+	u, err := url.Parse(strings.TrimSpace(raw))
+	if err != nil || u.Host == "" {
+		return raw
+	}
+	q := u.Query()
+	dropped := false
+	for key := range q {
+		switch strings.ToLower(key) {
+		case "api_key", "apikey", "x-emby-token", "x-mediabrowser-token":
+			q.Del(key)
+			dropped = true
+		}
+	}
+	if !dropped {
+		return raw
+	}
+	u.RawQuery = q.Encode()
+	return u.String()
+}
+
+// upstreamImageFetchURL forwards the client's thumbnail request to a configured
+// remote Emby mount. The remote server can produce the thumbnail itself from
+// maxWidth/maxHeight/quality, so the proxy transfers a few dozen KB instead of
+// the full-size original and skips the local decode+scale entirely (measured at
+// ~400ms for a single 2892×4096 poster).
+//
+// Other upstreams (TMDb, Douban, adult sites, ...) do not honour these
+// parameters, so their originals are still fetched and scaled locally.
+func (p *ImageProxy) upstreamImageFetchURL(raw string, opts imageResizeOptions) string {
+	if p == nil || !opts.active() {
+		return raw
+	}
+	u, err := url.Parse(raw)
+	if err != nil || u.Host == "" {
+		return raw
+	}
+	if !p.isAllowedRemoteHost(u.Hostname()) {
+		return raw
+	}
+	q := u.Query()
+	if opts.MaxWidth > 0 {
+		q.Set("maxWidth", strconv.Itoa(opts.MaxWidth))
+	}
+	if opts.MaxHeight > 0 {
+		q.Set("maxHeight", strconv.Itoa(opts.MaxHeight))
+	}
+	q.Set("quality", strconv.Itoa(opts.encodingQuality()))
+	u.RawQuery = q.Encode()
+	return u.String()
+}