Prioritize form-data/urlencoded for POST /fact-check and require claim when form used

cve_factchecker/app.py

@@ -70,29 +70,32 @@ def fact_check() -> Any:
     if request.method == 'GET':
         claim = request.args.get('claim') or request.args.get('text')
     else:  # POST
-        # 1) JSON payload
-        payload = request.get_json(silent=True) or {}
-        claim = payload.get('claim') or payload.get('text')
-        # 2) form-data / x-www-form-urlencoded
-        if not claim:
+        content_type = (request.content_type or '').lower()
+        # Prefer form-data / urlencoded strictly when provided (Postman Body: form-data)
+        if 'multipart/form-data' in content_type or 'application/x-www-form-urlencoded' in content_type:
+            # form fields first
             claim = request.form.get('claim') or request.form.get('text')
-        # 3) file upload in form-data ("file", "claim", or "claim_file")
-        if not claim and request.files:
-            f = (request.files.get('file') or request.files.get('claim') or request.files.get('claim_file'))
-            if f:
-                try:
-                    claim = (f.read() or b'').decode('utf-8', errors='ignore').strip()
-                except Exception:
-                    claim = None
-        # 4) raw text/plain body
-        if not claim:
-            content_type = (request.content_type or '').lower()
-            if 'text/plain' in content_type or (not payload and not request.form and not request.files):
+            # then file fields
+            if not claim and request.files:
+                f = (request.files.get('file') or request.files.get('claim') or request.files.get('claim_file'))
+                if f:
+                    try:
+                        claim = (f.read() or b'').decode('utf-8', errors='ignore').strip()
+                    except Exception:
+                        claim = None
+            if not claim:
+                return jsonify({"error": "Please provide claim via form-data: key 'claim' or 'text' (or upload file as 'file')."}), 400
+        else:
+            # JSON payload
+            payload = request.get_json(silent=True) or {}
+            claim = payload.get('claim') or payload.get('text')
+            # raw text/plain
+            if not claim and 'text/plain' in content_type:
                 raw = request.get_data(cache=False, as_text=True) or ''
                 claim = raw.strip()
-        # 5) query fallback (e.g., ?claim=... with POST)
-        if not claim:
-            claim = request.args.get('claim') or request.args.get('text')
+            # query fallback
+            if not claim:
+                claim = request.args.get('claim') or request.args.get('text')
     if not claim:
         return jsonify({"error": "claim parameter or JSON field 'claim' required"}), 400
     result, code = _run_fact_check(claim)