Switch to gunicorn, add /health endpoint

Dockerfile

@@ -8,8 +8,8 @@ COPY . .
 # Pre-compile the binary at image build time
 RUN gcc -O2 -o mdc mdc.c -lm
 
-RUN pip install --no-cache-dir flask
+RUN pip install --no-cache-dir flask gunicorn
 
 EXPOSE 7860
 
-CMD ["python", "app.py"]
+CMD ["gunicorn", "--bind", "0.0.0.0:7860", "--workers", "2", "--timeout", "120", "app:app"]

app.py

@@ -77,6 +77,11 @@ def fmt(n):
     return f"{n/1024**2:.2f} MB"
 
 
+@app.route("/health")
+def health():
+    return "ok", 200
+
+
 @app.route("/")
 def index():
     return render_template_string(HTML)
@@ -129,5 +134,4 @@ def decompress():
 
 
 if __name__ == "__main__":
-    print("Starting Midicoth server on 0.0.0.0:7860", flush=True)
     app.run(host="0.0.0.0", port=7860, debug=False)