Show Hugging Face model errors

app.py

@@ -11,6 +11,7 @@ import time
 from dataclasses import dataclass
 from html import escape
 from urllib.parse import quote
+from urllib.error import HTTPError, URLError
 from urllib.request import Request, urlopen
 
 import gradio as gr
@@ -248,9 +249,18 @@ def extract_json_object(text: str) -> dict | None:
     return value if isinstance(value, dict) else None
 
 
-def hf_prompt_json(html_code: str, role_lines: list[tuple[str, str]], style_hint: str) -> dict[str, str] | None:
+def short_error(exc: Exception) -> str:
+    if isinstance(exc, HTTPError):
+        body = exc.read().decode("utf-8", errors="replace")[:500]
+        return f"HTTP {exc.code}: {body}"
+    if isinstance(exc, URLError):
+        return f"URL error: {exc.reason}"
+    return f"{type(exc).__name__}: {str(exc)[:500]}"
+
+
+def hf_prompt_json(html_code: str, role_lines: list[tuple[str, str]], style_hint: str) -> tuple[dict[str, str] | None, str | None]:
     if not HF_TOKEN:
-        return None
+        return None, "HF_TOKEN is not visible to the Space runtime"
 
     role_block = "\n".join(f"- {role}: {prompt}" for role, prompt in role_lines)
     instruction = (
@@ -299,23 +309,23 @@ def hf_prompt_json(html_code: str, role_lines: list[tuple[str, str]], style_hint
             text = str(parsed)
         obj = extract_json_object(text)
         if not obj:
-            return None
+            return None, f"{HF_PROMPT_MODEL} returned non-JSON text: {text[:300]}"
         return {
             role: str(obj.get(role, "")).strip()
             for role, _ in role_lines
             if str(obj.get(role, "")).strip()
-        }
-    except Exception:
-        return None
+        }, None
+    except Exception as exc:
+        return None, short_error(exc)
 
 
-def build_prompt_map(html_code: str, raw_roles: str, style_hint: str) -> tuple[list[tuple[str, str]], dict[str, str], str]:
+def build_prompt_map(html_code: str, raw_roles: str, style_hint: str) -> tuple[list[tuple[str, str]], dict[str, str], str, str | None]:
     role_lines = parse_role_lines(raw_roles)
     local_map = local_prompt_map(role_lines, style_hint)
-    ai_map = hf_prompt_json(html_code, role_lines, style_hint)
+    ai_map, prompt_error = hf_prompt_json(html_code, role_lines, style_hint)
     if ai_map and all(role in ai_map for role, _ in role_lines):
-        return role_lines, ai_map, HF_PROMPT_MODEL
-    return role_lines, local_map, "local prompt interpreter"
+        return role_lines, ai_map, HF_PROMPT_MODEL, None
+    return role_lines, local_map, "local prompt interpreter", prompt_error
 
 
 def parse_assets(raw_roles: str, style_hint: str, prompt_map: dict[str, str] | None = None) -> list[AssetSpec]:
@@ -961,9 +971,9 @@ def placeholder_png_bytes(role: str, width: int, height: int) -> bytes:
     return out.getvalue()
 
 
-def hf_image_png(spec: AssetSpec, index: int, run_id: int) -> bytes | None:
+def hf_image_png(spec: AssetSpec, index: int, run_id: int) -> tuple[bytes | None, str | None]:
     if not HF_TOKEN:
-        return None
+        return None, "HF_TOKEN is not visible to the Space runtime"
 
     payload = {
         "inputs": spec.prompt,
@@ -991,14 +1001,15 @@ def hf_image_png(spec: AssetSpec, index: int, run_id: int) -> bytes | None:
             content_type = response.headers.get("content-type", "")
             content = response.read()
         if "image" not in content_type:
-            return None
-        return image_to_png_bytes(content, spec.width, spec.height)
-    except Exception:
-        return None
+            preview = content.decode("utf-8", errors="replace")[:500]
+            return None, f"{HF_IMAGE_MODEL} returned {content_type or 'non-image response'}: {preview}"
+        return image_to_png_bytes(content, spec.width, spec.height), None
+    except Exception as exc:
+        return None, short_error(exc)
 
 
 def generate_asset(spec: AssetSpec, index: int, run_id: int) -> tuple[str, str, str | None, str]:
-    png_content = hf_image_png(spec, index, run_id)
+    png_content, hf_error = hf_image_png(spec, index, run_id)
     source = HF_IMAGE_MODEL
     if png_content is None:
         png_content = local_asset_png(spec, index, run_id)
@@ -1006,7 +1017,7 @@ def generate_asset(spec: AssetSpec, index: int, run_id: int) -> tuple[str, str,
     return (
         png_bytes_to_data_uri(png_content),
         write_gallery_image(png_content, spec.role),
-        None if source == HF_IMAGE_MODEL else source,
+        hf_error if source == "local style fallback" else None,
         source,
     )
 
@@ -1167,7 +1178,7 @@ def generate_images_and_game(html_code: str, roles: str, style_hint: str):
     if not html_code.strip():
         return "", "Paste HTML game code first.", [], "", "", ""
 
-    role_lines, prompt_map, prompt_model = build_prompt_map(html_code, roles, style_hint or "pixel art style")
+    role_lines, prompt_map, prompt_model, prompt_error = build_prompt_map(html_code, roles, style_hint or "pixel art style")
     specs = parse_assets(roles, style_hint or "pixel art style", prompt_map)
     if not specs:
         return html_code, "Add at least one asset role, like `player: brave knight`.", [], "", "", build_preview(html_code)
@@ -1177,6 +1188,8 @@ def generate_images_and_game(html_code: str, roles: str, style_hint: str):
     errors = []
     model_rows = []
     run_id = time.time_ns()
+    if prompt_error:
+        errors.append(f"prompt model: {prompt_error}")
 
     for index, spec in enumerate(specs):
         data_uri, gallery_path, error, image_model = generate_asset(spec, index, run_id)
@@ -1184,7 +1197,7 @@ def generate_images_and_game(html_code: str, roles: str, style_hint: str):
         gallery.append((gallery_path, f"{spec.role} -> {spec.filename}"))
         model_rows.append((spec.role, prompt_model, image_model))
         if error:
-            errors.append(f"{spec.role}: fallback used ({error})")
+            errors.append(f"{spec.role}: image model failed ({error}); used local style fallback")
 
     rewritten = embed_assets(html_code, assets, specs)
     status = (
@@ -1192,7 +1205,7 @@ def generate_images_and_game(html_code: str, roles: str, style_hint: str):
         f"{summarize_model_sources(model_rows)}. Run {str(run_id)[-6:]}."
     )
     if errors:
-        status += "\n\n" + "\n".join(f"{item}: no HF image returned, used local style fallback" for item in [e.split(':', 1)[0] for e in errors])
+        status += "\n\n" + "\n".join(errors)
     return rewritten, status, gallery, build_prompt_preview(specs), build_model_report(model_rows), build_preview(rewritten)