ensure proxy urls have a host in front and not simple "/" path

src/api.rs

@@ -610,6 +610,12 @@ async fn videos_post(
                 }
             }
 
+            if let Some(base) = options.public_url_base.as_deref() {
+                for video in video_items.iter_mut() {
+                    video.ensure_proxy_host(base);
+                }
+            }
+
             videos.pageInfo = PageInfo {
                 hasNextPage: false,
                 resultsPerPage: perPage as u32,
@@ -659,6 +665,15 @@ async fn videos_post(
         video.id = format!("{}:{}", channel, video.id);
     }
 
+    // Cached items may have been built without a request host (e.g. by runtime
+    // validation), leaving host-relative `/proxy/...` URLs. Re-apply the host
+    // from this request so proxy URLs are always absolute.
+    if let Some(base) = options.public_url_base.as_deref() {
+        for video in video_items.iter_mut() {
+            video.ensure_proxy_host(base);
+        }
+    }
+
     // There is a bug in Hottub38 that makes the client error for a 403-url even though formats work fine
     if clientversion == ClientVersion::new(38, 0, "Hot%20Tub".to_string()) {
         // filter out videos without preview for old clients

src/providers/mod.rs

@@ -671,6 +671,22 @@ pub fn build_proxy_url(options: &ServerOptions, proxy: &str, target: &str) -> St
     }
 }
 
+/// Re-applies the public host to a (possibly host-relative) proxy URL.
+///
+/// Provider results are cached as fully-rendered items, so the `public_url_base`
+/// in effect when an item is *first* built gets baked into its proxy URLs. Items
+/// first produced by runtime validation (which has no request, so
+/// `public_url_base` is `None`) therefore carry host-relative `/proxy/...` URLs.
+/// Response handlers call this with the host derived from the incoming request so
+/// every proxy URL is absolute, regardless of which context populated the cache.
+pub fn ensure_proxy_url_host(url: &str, public_url_base: &str) -> String {
+    let base = public_url_base.trim_end_matches('/');
+    if base.is_empty() || !url.starts_with("/proxy/") {
+        return url.to_string();
+    }
+    format!("{base}{url}")
+}
+
 fn channel_metadata_for(id: &str) -> Option<ProviderChannelMetadata> {
     include!(concat!(env!("OUT_DIR"), "/provider_metadata_fn.rs"))
 }
@@ -1678,4 +1694,36 @@ mod tests {
             eprintln!("skipped providers:\n{}", skipped.join("\n"));
         }
     }
+
+    #[test]
+    fn ensure_proxy_url_host_prepends_host_to_relative_proxy_urls() {
+        // Host-relative proxy URL (as produced when public_url_base was None,
+        // e.g. by runtime validation) gets the request host applied.
+        assert_eq!(
+            ensure_proxy_url_host("/proxy/sxyprn/post/abc", "http://hottub:18080"),
+            "http://hottub:18080/proxy/sxyprn/post/abc"
+        );
+        // A trailing slash on the base is not duplicated.
+        assert_eq!(
+            ensure_proxy_url_host("/proxy/sxyprn/post/abc", "http://hottub:18080/"),
+            "http://hottub:18080/proxy/sxyprn/post/abc"
+        );
+        // Already-absolute URLs are left untouched.
+        assert_eq!(
+            ensure_proxy_url_host("https://cdn.example/v.mp4", "http://hottub:18080"),
+            "https://cdn.example/v.mp4"
+        );
+        assert_eq!(
+            ensure_proxy_url_host(
+                "http://other:18080/proxy/sxyprn/post/abc",
+                "http://hottub:18080"
+            ),
+            "http://other:18080/proxy/sxyprn/post/abc"
+        );
+        // Empty base leaves the URL as-is rather than producing a bare host.
+        assert_eq!(
+            ensure_proxy_url_host("/proxy/sxyprn/post/abc", ""),
+            "/proxy/sxyprn/post/abc"
+        );
+    }
 }

src/videos.rs

@@ -194,6 +194,22 @@ impl VideoItem {
         self
     }
 
+    /// Re-applies the request host to every host-relative proxy URL on this item
+    /// (its `url`, `preview`, and each format's `url`). Cached items may have been
+    /// built without a host; see [`crate::providers::ensure_proxy_url_host`].
+    pub fn ensure_proxy_host(&mut self, public_url_base: &str) {
+        self.url = crate::providers::ensure_proxy_url_host(&self.url, public_url_base);
+        if let Some(preview) = &self.preview {
+            self.preview =
+                Some(crate::providers::ensure_proxy_url_host(preview, public_url_base));
+        }
+        if let Some(formats) = &mut self.formats {
+            for format in formats.iter_mut() {
+                format.url = crate::providers::ensure_proxy_url_host(&format.url, public_url_base);
+            }
+        }
+    }
+
     #[cfg(any(
         not(hottub_single_provider),
         hottub_provider = "chaturbate",