From ae7bfdb5175e94d0b606883f98fd3324b5511170 Mon Sep 17 00:00:00 2001
From: Will Miao <willmiao.dev@gmail.com>
Date: Thu, 16 Apr 2026 18:25:16 +0800
Subject: [PATCH] fix(download): normalize civitai.red download URLs (#898)

---
 py/services/download_manager.py               | 11 +++++++---
 py/utils/civitai_utils.py                     | 18 +++++++++++++++
 .../test_download_manager_concurrent.py       |  4 ++--
 tests/utils/test_civitai_utils.py             | 22 +++++++++++++++++++
 4 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/py/services/download_manager.py b/py/services/download_manager.py
index 6ec5edd0..2fe07cff 100644
--- a/py/services/download_manager.py
+++ b/py/services/download_manager.py
@@ -16,7 +16,7 @@ from ..utils.constants import (
     SUPPORTED_DOWNLOAD_SKIP_BASE_MODELS,
     VALID_LORA_TYPES,
 )
-from ..utils.civitai_utils import rewrite_preview_url
+from ..utils.civitai_utils import normalize_civitai_download_url, rewrite_preview_url
 from ..utils.preview_selection import resolve_mature_threshold, select_preview_media
 from ..utils.utils import sanitize_folder_name
 from ..utils.exif_utils import ExifUtils
@@ -644,7 +644,9 @@ class DownloadManager:
             if mirrors:
                 for mirror in mirrors:
                     if mirror.get("deletedAt") is None and mirror.get("url"):
-                        download_urls.append(mirror["url"])
+                        download_urls.append(
+                            normalize_civitai_download_url(mirror["url"])
+                        )
 
                 # When source is 'civarchive', prioritize non-Civitai URLs
                 # This avoids failed downloads from deleted Civitai models
@@ -663,7 +665,9 @@ class DownloadManager:
             else:
                 download_url = file_info.get("downloadUrl")
                 if download_url:
-                    download_urls.append(download_url)
+                    download_urls.append(
+                        normalize_civitai_download_url(download_url)
+                    )
 
             if not download_urls:
                 return {"success": False, "error": "No mirror URL found"}
@@ -1138,6 +1142,7 @@ class DownloadManager:
                 pause_control.update_stall_timeout(downloader.stall_timeout)
             last_error = None
             for download_url in download_urls:
+                download_url = normalize_civitai_download_url(download_url)
                 use_auth = download_url.startswith(CIVITAI_DOWNLOAD_URL_PREFIXES)
                 download_kwargs = {
                     "progress_callback": lambda progress, snapshot=None: (
diff --git a/py/utils/civitai_utils.py b/py/utils/civitai_utils.py
index 07fc0057..7c2c9d11 100644
--- a/py/utils/civitai_utils.py
+++ b/py/utils/civitai_utils.py
@@ -119,6 +119,24 @@ def extract_civitai_image_id(url: str | None) -> str | None:
     return path_match.group(1)
 
 
+def normalize_civitai_download_url(url: str | None) -> str | None:
+    """Rewrite Civitai download URLs to the canonical authenticated host."""
+
+    if not url:
+        return url
+
+    try:
+        parsed = urlparse(url)
+    except ValueError:
+        return url
+
+    hostname = parsed.hostname.lower() if parsed.hostname else None
+    if hostname != "civitai.red" or not parsed.path.startswith("/api/download/"):
+        return url
+
+    return urlunparse(parsed._replace(netloc="civitai.com"))
+
+
 def extract_civitai_page_host(url: str | None) -> str | None:
     """Extract the supported Civitai page host from a URL."""
 
diff --git a/tests/services/test_download_manager_concurrent.py b/tests/services/test_download_manager_concurrent.py
index e6219663..2c520ccc 100644
--- a/tests/services/test_download_manager_concurrent.py
+++ b/tests/services/test_download_manager_concurrent.py
@@ -369,8 +369,8 @@ async def test_execute_download_uses_auth_for_red_civitai_downloads(monkeypatch,
     )
 
     assert result == {"success": True}
-    assert recorded_use_auth == [("https://civitai.red/api/download/models/119514", True)]
-    assert "https://civitai.red/api/download/".startswith(CIVITAI_DOWNLOAD_URL_PREFIXES)
+    assert recorded_use_auth == [("https://civitai.com/api/download/models/119514", True)]
+    assert "https://civitai.com/api/download/".startswith(CIVITAI_DOWNLOAD_URL_PREFIXES)
 
 
 @pytest.mark.asyncio
diff --git a/tests/utils/test_civitai_utils.py b/tests/utils/test_civitai_utils.py
index 7d2836fd..7f5a74e9 100644
--- a/tests/utils/test_civitai_utils.py
+++ b/tests/utils/test_civitai_utils.py
@@ -3,6 +3,7 @@ from py.utils.civitai_utils import (
     extract_civitai_image_id,
     extract_civitai_model_url_parts,
     is_supported_civitai_page_host,
+    normalize_civitai_download_url,
     resolve_license_info,
     resolve_license_payload,
 )
@@ -122,3 +123,24 @@ def test_extract_civitai_image_id_supports_red():
 
 def test_extract_civitai_image_id_rejects_non_civitai_host():
     assert extract_civitai_image_id("https://example.com/images/126920345") is None
+
+
+def test_normalize_civitai_download_url_rewrites_red_to_com():
+    url = "https://civitai.red/api/download/models/2786889?type=Model&format=SafeTensor"
+
+    assert (
+        normalize_civitai_download_url(url)
+        == "https://civitai.com/api/download/models/2786889?type=Model&format=SafeTensor"
+    )
+
+
+def test_normalize_civitai_download_url_keeps_non_download_red_urls():
+    url = "https://civitai.red/models/65423/nijimecha-artstyle?modelVersionId=777"
+
+    assert normalize_civitai_download_url(url) == url
+
+
+def test_normalize_civitai_download_url_keeps_existing_com_urls():
+    url = "https://civitai.com/api/download/models/2786889?type=Model&format=SafeTensor"
+
+    assert normalize_civitai_download_url(url) == url