fix(import): preserve apostrophes in valid JSON imports

parse_json unconditionally replaced every single quote with a double
quote (`.replace("'", '"')`) before calling json.loads. This corrupted
any valid JSON string value containing an apostrophe, e.g. a person's
surname "Sarah O'Brien" became "Sarah O"Brien", causing the parse to
fail with "Invalid JSON" and the whole import to be rejected.

Parse strict JSON first so well-formed payloads (including apostrophes
in string values) import correctly, and only fall back to the lenient
single-quote replacement for Python-dict-style payloads that are not
valid JSON on their own.

Adds regression tests covering an apostrophe-bearing JSON value and the
retained single-quoted fallback.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

flowsint-core/src/flowsint_core/imports/json/parse_json.py

@@ -23,8 +23,15 @@ def parse_json(
     try:
         file_bytes = file_bytes.lstrip()
         entities: Dict[str, Entity] = {}
-        my_bytes_value = file_bytes.decode().replace("'", '"')
-        graph = json.loads(my_bytes_value)
+        decoded = file_bytes.decode()
+        # Parse strict JSON first so apostrophes inside string values (e.g.
+        # "Sarah O'Brien") are preserved. Only fall back to the lenient
+        # single-quote replacement for Python-dict-style payloads that are not
+        # valid JSON on their own.
+        try:
+            graph = json.loads(decoded)
+        except json.JSONDecodeError:
+            graph = json.loads(decoded.replace("'", '"'))
         node_key = next((k for k in VALID_NODES_KEYS if k in graph), None)
         edge_key = next((k for k in VALID_EDGES_KEYS if k in graph), None)
         if node_key is None:

flowsint-core/tests/import/json/test_json_import.py

@@ -65,3 +65,40 @@ def test_standard_json_import_without_label():
     """Test basic standard JSON import."""
     results = parse_json(standard_json_without_label, max_preview_rows=100)
     assert "Username" in results.entities
+
+
+# Valid JSON whose string values contain apostrophes (very common in OSINT
+# data, e.g. surnames like "O'Brien"). This is well-formed JSON and must import.
+json_with_apostrophe = b"""{
+  "nodes": [
+    {"id": "1", "label": "Sarah O'Brien", "type": "individual"},
+    {"id": "2", "label": "Bob", "type": "individual"}
+  ],
+  "edges": [
+    {"source": "1", "target": "2", "label": "KNOWS"}
+  ]
+}"""
+
+
+def test_json_import_preserves_apostrophes_in_string_values():
+    """Valid JSON with an apostrophe in a value must parse and keep the value.
+
+    Regression: the parser used to blindly replace every single quote with a
+    double quote, which corrupted valid JSON (turning "Sarah O'Brien" into
+    "Sarah O"Brien") and raised "Invalid JSON".
+    """
+    results = parse_json(json_with_apostrophe, max_preview_rows=100)
+
+    assert "Individual" in results.entities
+    labels = {
+        str(preview.obj.nodeLabel)
+        for preview in results.entities["Individual"].results
+    }
+    assert "Sarah O'Brien" in labels
+
+
+def test_json_import_still_accepts_single_quoted_payload():
+    """Python-dict-style payloads (single-quoted) remain supported as fallback."""
+    single_quoted = b"{'nodes': [{'id': '1', 'label': 'Alice', 'type': 'individual'}], 'edges': []}"
+    results = parse_json(single_quoted, max_preview_rows=100)
+    assert "Individual" in results.entities