From cf2940be05954427a89547203968014002b743e3 Mon Sep 17 00:00:00 2001
From: Gabriel Luiz Freitas Almeida <gabriel@logspace.ai>
Date: Thu, 17 Aug 2023 17:58:10 -0300
Subject: [PATCH] =?UTF-8?q?=E2=9C=A8=20feat(session):=20add=20SessionManag?=
 =?UTF-8?q?erFactory,=20SessionManager,=20and=20related=20methods?=
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- Added `SessionManagerFactory` class in `src/backend/langflow/services/session/factory.py` to create instances of `SessionManager`.
- Added `SessionManager` class in `src/backend/langflow/services/session/manager.py` to manage sessions.
- Added `load_session`, `generate_key`, `update_session`, and `clear_session` methods to `SessionManager` to handle session-related logic.

These changes were made to introduce session management functionality to the application.
---
 .../langflow/services/session/__init__.py     |  0
 .../langflow/services/session/factory.py      | 14 +++++++
 .../langflow/services/session/manager.py      | 38 +++++++++++++++++++
 3 files changed, 52 insertions(+)
 create mode 100644 src/backend/langflow/services/session/__init__.py
 create mode 100644 src/backend/langflow/services/session/factory.py
 create mode 100644 src/backend/langflow/services/session/manager.py

diff --git a/src/backend/langflow/services/session/__init__.py b/src/backend/langflow/services/session/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/src/backend/langflow/services/session/factory.py b/src/backend/langflow/services/session/factory.py
new file mode 100644
index 000000000..42b33e70f
--- /dev/null
+++ b/src/backend/langflow/services/session/factory.py
@@ -0,0 +1,14 @@
+from typing import TYPE_CHECKING
+from langflow.services.session.manager import SessionManager
+from langflow.services.factory import ServiceFactory
+
+if TYPE_CHECKING:
+    from langflow.services.cache.manager import BaseCacheManager
+
+
+class SessionManagerFactory(ServiceFactory):
+    def __init__(self):
+        super().__init__(SessionManager)
+
+    def create(self, cache_manager: "BaseCacheManager"):
+        return SessionManager(cache_manager)
diff --git a/src/backend/langflow/services/session/manager.py b/src/backend/langflow/services/session/manager.py
new file mode 100644
index 000000000..39cefba24
--- /dev/null
+++ b/src/backend/langflow/services/session/manager.py
@@ -0,0 +1,38 @@
+from langflow.interface.run import build_sorted_vertices
+from langflow.services.base import Service
+from langflow.services.cache.utils import compute_dict_hash
+
+
+class SessionManager(Service):
+    name = "session_manager"
+
+    def __init__(self, cache_manager):
+        self.cache_manager = cache_manager
+
+    def load_session(self, session_id, data_graph):
+        key = self.generate_key(session_id, data_graph)
+
+        # Check if the data is cached
+        if key in self.cache_manager:
+            return self.cache_manager.get(key)
+
+        # If not cached, build the graph and cache it
+        graph, artifacts = build_sorted_vertices(data_graph)
+        self.cache_manager.set(key, (graph, artifacts))
+
+        return graph, artifacts
+
+    def generate_key(self, session_id, data_graph):
+        # Hash the JSON and combine it with the session_id to create a unique key
+        json_hash = compute_dict_hash(data_graph)
+        return f"{session_id}{':' if session_id else ''}{json_hash}"
+
+    def update_session(self, session_id, data_graph, value):
+        key = self.generate_key(session_id, data_graph)
+        self.cache_manager.set(key, value)
+
+    def clear_session(self, session_id, data_graph):
+        key = self.generate_key(session_id, data_graph)
+        self.cache_manager.delete(key)
+
+    # Additional methods to handle session-related logic