fix: load_flow_from_json now uses the Graph

src/backend/langflow/interface/loading.py

@@ -52,17 +52,13 @@ def instantiate_class(node_type: str, base_type: str, params: Dict) -> Any:
 
 
 def load_flow_from_json(path: str):
+    # This is done to avoid circular imports
+    from langflow.graph.graph import Graph
+
     """Load flow from json file"""
     with open(path, "r") as f:
         flow_graph = json.load(f)
     data_graph = flow_graph["data"]
-    extracted_json = extract_json(data_graph)
-    return load_langchain_type_from_config(config=extracted_json)
-
-
-def extract_json(data_graph):
-    from langflow.graph.graph import Graph
-
     nodes = data_graph["nodes"]
     # Substitute ZeroShotPrompt with PromptTemplate
     nodes = replace_zero_shot_prompt_with_prompt_template(nodes)
@@ -71,8 +67,7 @@ def extract_json(data_graph):
     # Nodes, edges and root node
     edges = data_graph["edges"]
     graph = Graph(nodes, edges)
-    root = payload.get_root_node(graph)
-    return payload.build_json(root, graph)
+    return graph.build()
 
 
 def replace_zero_shot_prompt_with_prompt_template(nodes):

tests/test_loading.py

@@ -1,27 +1,17 @@
 import json
-from langchain import LLMChain, OpenAI
 from langflow.graph.graph import Graph
 import pytest
 
 from langflow import load_flow_from_json
-from langflow.interface.loading import extract_json
-from langflow.utils.payload import get_root_node, build_json
-from langflow.interface.loading import load_langchain_type_from_config
+from langflow.utils.payload import get_root_node
+from langchain.agents import AgentExecutor
 
 
 def test_load_flow_from_json():
     """Test loading a flow from a json file"""
     loaded = load_flow_from_json(pytest.BASIC_EXAMPLE_PATH)
     assert loaded is not None
-
-
-def test_extract_json():
-    with open(pytest.BASIC_EXAMPLE_PATH, "r") as f:
-        flow_graph = json.load(f)
-    data_graph = flow_graph["data"]
-    extracted = extract_json(data_graph)
-    assert extracted is not None
-    assert isinstance(extracted, dict)
+    assert isinstance(loaded, AgentExecutor)
 
 
 def test_get_root_node():
@@ -35,83 +25,3 @@ def test_get_root_node():
     assert root is not None
     assert hasattr(root, "id")
     assert hasattr(root, "data")
-
-
-def test_build_json():
-    with open(pytest.BASIC_EXAMPLE_PATH, "r") as f:
-        flow_graph = json.load(f)
-    data_graph = flow_graph["data"]
-    nodes = data_graph["nodes"]
-    edges = data_graph["edges"]
-    graph = Graph(nodes, edges)
-    root = get_root_node(graph)
-    built_json = build_json(root, graph)
-    assert built_json is not None
-    assert isinstance(built_json, dict)
-
-
-def test_build_json_missing_child():
-    with open(pytest.BASIC_EXAMPLE_PATH, "r") as f:
-        flow_graph = json.load(f)
-    data_graph = flow_graph["data"]
-    nodes = data_graph["nodes"]
-    edges = data_graph["edges"]
-
-    # Modify nodes to create a missing required child scenario
-    for node in nodes:
-        if "data" in node and "node" in node["data"]:
-            for key, value in node["data"]["node"]["template"].items():
-                if isinstance(value, dict) and "required" in value:
-                    value["required"] = True
-
-    with pytest.raises(ValueError):
-        graph = Graph(nodes, edges)
-        root = get_root_node(graph)
-        build_json(root, graph)
-
-
-def test_build_json_no_nodes():
-    with pytest.raises(TypeError):
-        build_json(None, [], [])
-
-
-def test_build_json_invalid_edge():
-    with open(pytest.BASIC_EXAMPLE_PATH, "r") as f:
-        flow_graph = json.load(f)
-    data_graph = flow_graph["data"]
-    nodes = data_graph["nodes"]
-    edges = data_graph["edges"]
-    # Modify edges to create an invalid edge scenario
-    for edge in edges:
-        edge["source"] = "invalid_id"
-
-    with pytest.raises(ValueError):
-        graph = Graph(nodes, edges)
-        root = get_root_node(graph)
-        build_json(root, nodes, edges)
-
-
-def test_load_langchain_type_from_config():
-    with open(pytest.BASIC_EXAMPLE_PATH, "r") as f:
-        flow_graph = json.load(f)
-    data_graph = flow_graph["data"]
-    extracted = extract_json(data_graph)
-
-    agent_config = extracted.copy()
-    agent_type = "AgentExecutor"  # Replace with the actual agent type in the JSON
-
-    invalid_config = extracted.copy()
-    invalid_config["_type"] = "invalid_type"
-
-    agent_loaded = load_langchain_type_from_config(agent_config)
-    assert agent_loaded is not None
-    assert agent_loaded.__class__.__name__ == agent_type
-    assert hasattr(agent_loaded.agent, "llm_chain")
-    assert isinstance(
-        agent_loaded.agent.llm_chain, LLMChain
-    )  # Replace Chain with the appropriate class
-    assert hasattr(agent_loaded.agent.llm_chain, "llm")
-    assert isinstance(agent_loaded.agent.llm_chain.llm, OpenAI)
-
-    with pytest.raises(ValueError):
-        load_langchain_type_from_config(invalid_config)