add gzip

main.py

@@ -1,12 +1,37 @@
-from flask import Flask, Response
+from flask import Flask, Response, request
 
 app = Flask(__name__)
 
+with open("bomb.png.br", "rb") as f:
+    BOMB_BR = f.read()
+
+with open("bomb.png.gz", "rb") as f:
+    BOMB_GZIP = f.read()
+
+print(f"[startup] br={len(BOMB_BR):,} bytes  gzip={len(BOMB_GZIP):,} bytes")
+
+
+def _pick_encoding():
+    accept = request.headers.get("Accept-Encoding", "")
+    if "br" in accept:
+        return "br", BOMB_BR
+    if "gzip" in accept:
+        return "gzip", BOMB_GZIP
+    return "gzip", BOMB_GZIP
+
 
 @app.route("/")
 def index():
-    data = open("bomb.png.br", "rb").read()
-    return Response(data, mimetype="image/png", headers={"Content-Encoding": "br"})
+    encoding, body = _pick_encoding()
+    return Response(
+        body,
+        mimetype="image/png",
+        headers={
+            "Content-Encoding": encoding,
+            "Content-Length": str(len(body)),
+            "Vary": "Accept-Encoding",
+        },
+    )
 
 
-app.run(host="0.0.0.0", port=8080)
+app.run(host="0.0.0.0", port=8393, threaded=True)