Restore self message sent before OSX 12 Monterey (#14818)

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libs/community/langchain_community/chat_loaders/imessage.py

@@ -91,8 +91,38 @@ class IMessageChatLoader(BaseChatLoader):
             length, start = int.from_bytes(content[1:3], "little"), 3
         return content[start : start + length].decode("utf-8", errors="ignore")
 
+    def _get_session_query(self, use_chat_handle_table: bool) -> str:
+        # Messages sent pre OSX 12 require a join through the chat_handle_join table
+        # However, the table doesn't exist if database created with OSX 12 or above.
+
+        joins_w_chat_handle = """
+            JOIN chat_handle_join ON
+                 chat_message_join.chat_id = chat_handle_join.chat_id
+            JOIN handle ON
+                 handle.ROWID = chat_handle_join.handle_id"""
+
+        joins_no_chat_handle = """
+            JOIN handle ON message.handle_id = handle.ROWID
+        """
+
+        joins = joins_w_chat_handle if use_chat_handle_table else joins_no_chat_handle
+
+        return f"""
+            SELECT  message.date,
+                    handle.id,
+                    message.text,
+                    message.is_from_me,
+                    message.attributedBody
+            FROM message
+            JOIN chat_message_join ON
+                 message.ROWID = chat_message_join.message_id
+            {joins}
+            WHERE chat_message_join.chat_id = ?
+            ORDER BY message.date ASC;
+        """
+
     def _load_single_chat_session(
-        self, cursor: "sqlite3.Cursor", chat_id: int
+        self, cursor: "sqlite3.Cursor", use_chat_handle_table: bool, chat_id: int
     ) -> ChatSession:
         """
         Load a single chat session from the iMessage chat.db.
@@ -106,14 +136,7 @@ class IMessageChatLoader(BaseChatLoader):
         """
         results: List[HumanMessage] = []
 
-        query = """
+        query = self._get_session_query(use_chat_handle_table)
-        SELECT message.date, handle.id, message.text, message.is_from_me, message.attributedBody
-        FROM message
-        JOIN chat_message_join ON message.ROWID = chat_message_join.message_id
-        JOIN handle ON message.handle_id = handle.ROWID
-        WHERE chat_message_join.chat_id = ?
-        ORDER BY message.date ASC;
-        """  # noqa: E501
         cursor.execute(query, (chat_id,))
         messages = cursor.fetchall()
 
@@ -165,6 +188,13 @@ class IMessageChatLoader(BaseChatLoader):
             ) from e
         cursor = conn.cursor()
 
+        # See if chat_handle_join table exists:
+        query = """SELECT name FROM sqlite_master
+                   WHERE type='table' AND name='chat_handle_join';"""
+
+        cursor.execute(query)
+        is_chat_handle_join_exists = cursor.fetchone()
+
         # Fetch the list of chat IDs sorted by time (most recent first)
         query = """SELECT chat_id
         FROM message
@@ -175,6 +205,8 @@ class IMessageChatLoader(BaseChatLoader):
         chat_ids = [row[0] for row in cursor.fetchall()]
 
         for chat_id in chat_ids:
-            yield self._load_single_chat_session(cursor, chat_id)
+            yield self._load_single_chat_session(
+                cursor, is_chat_handle_join_exists, chat_id
+            )
 
         conn.close()

libs/community/tests/unit_tests/chat_loaders/test_imessage.py

@@ -4,6 +4,41 @@ import pathlib
 from langchain_community.chat_loaders import imessage, utils
 
 
+def test_imessage_chat_loader_upgrade_osx11() -> None:
+    chat_path = (
+        pathlib.Path(__file__).parent / "data" / "imessage_chat_upgrade_osx_11.db"
+    )
+    loader = imessage.IMessageChatLoader(str(chat_path))
+
+    chat_sessions = list(
+        utils.map_ai_messages(loader.lazy_load(), sender="testemail@gmail.com")
+    )
+    assert chat_sessions, "Chat sessions should not be empty"
+
+    assert chat_sessions[0]["messages"], "Chat messages should not be empty"
+
+    first_message = chat_sessions[0]["messages"][0]
+    # message content in text field
+    assert "Yeh" in first_message.content, "Chat content mismatch"
+
+    # time parsed correctly
+    expected_message_time = 720845450393148160
+    assert (
+        first_message.additional_kwargs["message_time"] == expected_message_time
+    ), "unexpected time"
+
+    expected_parsed_time = datetime.datetime(2023, 11, 5, 2, 50, 50, 393148)
+    assert (
+        first_message.additional_kwargs["message_time_as_datetime"]
+        == expected_parsed_time
+    ), "date failed to parse"
+
+    # is_from_me parsed correctly
+    assert (
+        first_message.additional_kwargs["is_from_me"] is False
+    ), "is_from_me failed to parse"
+
+
 def test_imessage_chat_loader() -> None:
     chat_path = pathlib.Path(__file__).parent / "data" / "imessage_chat.db"
     loader = imessage.IMessageChatLoader(str(chat_path))