Spaces: switch to Python 3.10 and preinstall PyYAML/Cython

Dockerfile

@@ -1,30 +1,27 @@
-# ---- Base image ----
-FROM python:3.11-slim
+# Dockerfile
+FROM python:3.10-slim
 
-# ---- System setup (add OS libs your deps may need) ----
-# Add or remove packages as needed. Keep it small to speed builds.
+# Build tools
 RUN apt-get update && apt-get install -y --no-install-recommends \
     build-essential \
-    && rm -rf /var/lib/apt/lists/*
+ && rm -rf /var/lib/apt/lists/*
 
-# ---- App files ----
 WORKDIR /app
-# Copy only requirements first to leverage Docker layer caching
+
+# Upgrade pip toolchain and preinstall deps that unblock tf-models-official
+RUN pip install --no-cache-dir --upgrade pip setuptools wheel \
+ && pip install --no-cache-dir "Cython<3" "pyyaml<5.4.0,>=5.1"
+
+# Then install your requirements
 COPY requirements.txt /app/requirements.txt
 RUN pip install --no-cache-dir -r requirements.txt
 
-# Now copy the rest of your code
+# App code
 COPY . /app
 
-# ---- Runtime env ----
-# HF Spaces provides a PORT env var; default to 7860 for local runs
-ENV PORT=7860
-ENV PYTHONUNBUFFERED=1
-
-# Make sure Flask binds publicly; gunicorn will use $PORT
+ENV PORT=7860 PYTHONUNBUFFERED=1
 EXPOSE 7860
 
-# ---- Start command ----
-# Gunicorn will import your Flask app named "app" from run.py
-# If your app variable has a different name, change run:app accordingly.
+# Gunicorn loads Flask app from run.py
 CMD ["gunicorn", "run:app", "--workers", "2", "--threads", "8", "--timeout", "120", "--bind", "0.0.0.0:${PORT}"]
+