feat(server): GET /segments endpoint — JSON in seconds, gzip, CORS, cache

pyproject.toml

@@ -28,6 +28,9 @@ server = [
     "Flask",
     "Werkzeug",
     "gunicorn",
+    "Flask-Cors",
+    "Flask-Compress",
+    "Flask-Caching",
 ]
 
 [tool.ruff]

sign_language_segmentation/server.py

@@ -4,18 +4,42 @@
 from pathlib import Path
 
 from flask import Flask, request, abort, make_response, jsonify
+from flask_caching import Cache
+from flask_compress import Compress
+from flask_cors import CORS
 from pose_format import Pose
 
 from sign_language_segmentation.bin import segment_pose
 
 app = Flask(__name__)
+compress = Compress(app)
+cache = Cache(app, config={"CACHE_TYPE": "SimpleCache"})
+CORS(app, resources={r"/": {"methods": ["GET", "OPTIONS"]}})
+
+CACHE_TTL = 86400  # 1 day in seconds
 
 
 def resolve_path(uri: str):
     # Map gs:// URIs to the gcsfuse mount point, or return as-is
     return uri.replace("gs://", "/mnt/")
 
 
+def load_pose(uri: str) -> Pose:
+    pose_file_path = Path(resolve_path(uri))
+    if not pose_file_path.exists():
+        raise FileNotFoundError(f"File does not exist: {uri}")
+    with pose_file_path.open("rb") as f:
+        return Pose.read(f)
+
+
+def tiers_to_seconds(tiers: dict, fps: float) -> dict:
+    return {
+        tier: [{"start": round(seg["start"] / fps, 3), "end": round(seg["end"] / fps, 3)}
+               for seg in segments]
+        for tier, segments in tiers.items()
+    }
+
+
 @app.errorhandler(Exception)
 def handle_exception(e):
     print("Exception", e)
@@ -38,6 +62,30 @@ def health_check():
     return make_response(jsonify(body), 200)
 
 
+@app.route("/", methods=['GET', 'OPTIONS'])
+@compress.compressed()
+@cache.cached(timeout=CACHE_TTL, query_string=True)
+def get_segments():
+    if request.method == 'OPTIONS':
+        return make_response("", 204)
+
+    pose_uri = request.args.get("pose")
+    if not pose_uri:
+        abort(make_response(jsonify(message="Missing `pose` query parameter"), 400))
+
+    pose = load_pose(pose_uri)
+
+    if len(pose.body.data) == 1:
+        return jsonify(sign=[], sentence=[])
+
+    _eaf, tiers = segment_pose(pose)
+    result = tiers_to_seconds(tiers, pose.body.fps)
+
+    response = make_response(jsonify(sign=result["SIGN"], sentence=result["SENTENCE"]))
+    response.headers["Cache-Control"] = f"public, max-age={CACHE_TTL}"
+    return response
+
+
 @app.route("/", methods=['POST'])
 def pose_segmentation():
     body = request.get_json()
@@ -49,18 +97,12 @@ def pose_segmentation():
     if output_file_path.exists():
         return make_response(jsonify(message="Output file already exists", path=body["output"]), 208)
 
-    pose_file_path = Path(resolve_path(body["input"]))
-    if not pose_file_path.exists():
-        raise FileNotFoundError("File does not exist")
-
-    with pose_file_path.open("rb") as f:
-        pose = Pose.read(f)
+    pose = load_pose(body["input"])
 
     if len(pose.body.data) == 1:
-        # segment_pose would error on a single-frame pose
         return make_response(jsonify(message="Pose has only one frame, no segmentation needed", path=body["output"]), 200)
 
-    eaf, tiers = segment_pose(pose)
+    eaf, _tiers = segment_pose(pose)
 
     output_file_path.parent.mkdir(parents=True, exist_ok=True)
     print("Saving .eaf to disk ...")