feat: Add possibility to save flow to FS (#6841)

Add possibility to save flow to FS

src/backend/base/langflow/alembic/versions/93e2705fa8d6_add_column_save_path_to_flow.py

@@ -0,0 +1,43 @@
+"""Add column fs_path to Flow
+
+Revision ID: 93e2705fa8d6
+Revises: dd9e0804ebd1
+Create Date: 2025-02-25 13:08:11.263504
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+import sqlmodel
+from sqlalchemy.engine.reflection import Inspector
+from langflow.utils import migration
+
+
+# revision identifiers, used by Alembic.
+revision: str = '93e2705fa8d6'
+down_revision: Union[str, None] = 'dd9e0804ebd1'
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    conn = op.get_bind()
+    inspector = sa.inspect(conn)  # type: ignore
+    # ### commands auto generated by Alembic - please adjust! ###
+    column_names = [column["name"] for column in inspector.get_columns("flow")]
+    with op.batch_alter_table("flow", schema=None) as batch_op:
+        if "fs_path" not in column_names:
+            batch_op.add_column(sa.Column("fs_path", sqlmodel.sql.sqltypes.AutoString(), nullable=True))
+
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    conn = op.get_bind()
+    inspector = sa.inspect(conn)  # type: ignore
+    # ### commands auto generated by Alembic - please adjust! ###
+    column_names = [column["name"] for column in inspector.get_columns("flow")]
+    with op.batch_alter_table("flow", schema=None) as batch_op:
+        if "fs_path" in column_names:
+            batch_op.drop_column("fs_path")

src/backend/base/langflow/api/utils.py

@@ -40,13 +40,12 @@ def has_api_terms(word: str):
 
 def remove_api_keys(flow: dict):
     """Remove api keys from flow data."""
-    if flow.get("data") and flow["data"].get("nodes"):
+    for node in flow.get("data", {}).get("nodes", []):
-        for node in flow["data"]["nodes"]:
+        node_data = node.get("data").get("node")
-            node_data = node.get("data").get("node")
+        template = node_data.get("template")
-            template = node_data.get("template")
+        for value in template.values():
-            for value in template.values():
+            if isinstance(value, dict) and has_api_terms(value["name"]) and value.get("password"):
-                if isinstance(value, dict) and has_api_terms(value["name"]) and value.get("password"):
+                value["value"] = None
-                    value["value"] = None
 
     return flow
 

src/backend/base/langflow/api/v1/flows.py

@@ -9,6 +9,8 @@ from typing import Annotated
 from uuid import UUID
 
 import orjson
+from aiofile import async_open
+from anyio import Path
 from fastapi import APIRouter, Depends, File, HTTPException, UploadFile
 from fastapi.encoders import jsonable_encoder
 from fastapi.responses import StreamingResponse
@@ -20,6 +22,7 @@ from sqlmodel.ext.asyncio.session import AsyncSession
 from langflow.api.utils import CurrentActiveUser, DbSession, cascade_delete_flow, remove_api_keys, validate_is_component
 from langflow.api.v1.schemas import FlowListCreate
 from langflow.initial_setup.constants import STARTER_FOLDER_NAME
+from langflow.logging import logger
 from langflow.services.database.models.flow import Flow, FlowCreate, FlowRead, FlowUpdate
 from langflow.services.database.models.flow.model import FlowHeader
 from langflow.services.database.models.flow.utils import get_webhook_component_in_flow
@@ -32,6 +35,22 @@ from langflow.services.settings.service import SettingsService
 router = APIRouter(prefix="/flows", tags=["Flows"])
 
 
+async def _verify_fs_path(path: str | None) -> None:
+    if path:
+        path_ = Path(path)
+        if not await path_.exists():
+            await path_.touch()
+
+
+async def _save_flow_to_fs(flow: Flow) -> None:
+    if flow.fs_path:
+        async with async_open(flow.fs_path, "w") as f:
+            try:
+                await f.write(flow.model_dump_json())
+            except OSError:
+                logger.exception("Failed to write flow %s to path %s", flow.name, flow.fs_path)
+
+
 async def _new_flow(
     *,
     session: AsyncSession,
@@ -39,6 +58,8 @@ async def _new_flow(
     user_id: UUID,
 ):
     try:
+        await _verify_fs_path(flow.fs_path)
+
         """Create a new flow."""
         if flow.user_id is None:
             flow.user_id = user_id
@@ -124,6 +145,9 @@ async def create_flow(
         db_flow = await _new_flow(session=session, flow=flow, user_id=current_user.id)
         await session.commit()
         await session.refresh(db_flow)
+
+        await _save_flow_to_fs(db_flow)
+
     except Exception as e:
         if "UNIQUE constraint failed" in str(e):
             # Get the name of the column that failed
@@ -283,6 +307,8 @@ async def update_flow(
         for key, value in update_data.items():
             setattr(db_flow, key, value)
 
+        await _verify_fs_path(db_flow.fs_path)
+
         webhook_component = get_webhook_component_in_flow(db_flow.data)
         db_flow.webhook = webhook_component is not None
         db_flow.updated_at = datetime.now(timezone.utc)
@@ -296,6 +322,8 @@ async def update_flow(
         await session.commit()
         await session.refresh(db_flow)
 
+        await _save_flow_to_fs(db_flow)
+
     except Exception as e:
         if "UNIQUE constraint failed" in str(e):
             # Get the name of the column that failed
@@ -381,6 +409,7 @@ async def upload_file(
         await session.commit()
         for db_flow in response_list:
             await session.refresh(db_flow)
+            await _save_flow_to_fs(db_flow)
     except Exception as e:
         if "UNIQUE constraint failed" in str(e):
             # Get the name of the column that failed

src/backend/base/langflow/services/database/models/flow/model.py

@@ -169,6 +169,7 @@ class Flow(FlowBase, table=True):  # type: ignore[call-arg]
     tags: list[str] | None = Field(sa_column=Column(JSON), default=[])
     locked: bool | None = Field(default=False, nullable=True)
     folder_id: UUID | None = Field(default=None, foreign_key="folder.id", nullable=True, index=True)
+    fs_path: str | None = Field(default=None, nullable=True)
     folder: Optional["Folder"] = Relationship(back_populates="flows")
     messages: list["MessageTable"] = Relationship(back_populates="flow")
     transactions: list["TransactionTable"] = Relationship(back_populates="flow")
@@ -194,6 +195,7 @@ class Flow(FlowBase, table=True):  # type: ignore[call-arg]
 class FlowCreate(FlowBase):
     user_id: UUID | None = None
     folder_id: UUID | None = None
+    fs_path: str | None = None
 
 
 class FlowRead(FlowBase):
@@ -233,6 +235,7 @@ class FlowUpdate(SQLModel):
     folder_id: UUID | None = None
     endpoint_name: str | None = None
     locked: bool | None = None
+    fs_path: str | None = None
 
     @field_validator("endpoint_name")
     @classmethod

src/backend/tests/unit/api/v1/test_flows.py

@@ -1,41 +1,54 @@
+import tempfile
+import uuid
+
+from anyio import Path
 from fastapi import status
 from httpx import AsyncClient
+from langflow.services.database.models import Flow
 
 
 async def test_create_flow(client: AsyncClient, logged_in_headers):
-    basic_case = {
+    flow_file = Path(tempfile.tempdir) / f"{uuid.uuid4()!s}.json"
-        "name": "string",
+    try:
-        "description": "string",
+        basic_case = {
-        "icon": "string",
+            "name": "string",
-        "icon_bg_color": "#ff00ff",
+            "description": "string",
-        "gradient": "string",
+            "icon": "string",
-        "data": {},
+            "icon_bg_color": "#ff00ff",
-        "is_component": False,
+            "gradient": "string",
-        "webhook": False,
+            "data": {},
-        "endpoint_name": "string",
+            "is_component": False,
-        "tags": ["string"],
+            "webhook": False,
-        "user_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
+            "endpoint_name": "string",
-        "folder_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
+            "tags": ["string"],
-    }
+            "user_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
-    response = await client.post("api/v1/flows/", json=basic_case, headers=logged_in_headers)
+            "folder_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
-    result = response.json()
+            "fs_path": str(flow_file),
+        }
+        response = await client.post("api/v1/flows/", json=basic_case, headers=logged_in_headers)
+        result = response.json()
 
-    assert response.status_code == status.HTTP_201_CREATED
+        assert response.status_code == status.HTTP_201_CREATED
-    assert isinstance(result, dict), "The result must be a dictionary"
+        assert isinstance(result, dict), "The result must be a dictionary"
-    assert "data" in result, "The result must have a 'data' key"
+        assert "data" in result, "The result must have a 'data' key"
-    assert "description" in result, "The result must have a 'description' key"
+        assert "description" in result, "The result must have a 'description' key"
-    assert "endpoint_name" in result, "The result must have a 'endpoint_name' key"
+        assert "endpoint_name" in result, "The result must have a 'endpoint_name' key"
-    assert "folder_id" in result, "The result must have a 'folder_id' key"
+        assert "folder_id" in result, "The result must have a 'folder_id' key"
-    assert "gradient" in result, "The result must have a 'gradient' key"
+        assert "gradient" in result, "The result must have a 'gradient' key"
-    assert "icon" in result, "The result must have a 'icon' key"
+        assert "icon" in result, "The result must have a 'icon' key"
-    assert "icon_bg_color" in result, "The result must have a 'icon_bg_color' key"
+        assert "icon_bg_color" in result, "The result must have a 'icon_bg_color' key"
-    assert "id" in result, "The result must have a 'id' key"
+        assert "id" in result, "The result must have a 'id' key"
-    assert "is_component" in result, "The result must have a 'is_component' key"
+        assert "is_component" in result, "The result must have a 'is_component' key"
-    assert "name" in result, "The result must have a 'name' key"
+        assert "name" in result, "The result must have a 'name' key"
-    assert "tags" in result, "The result must have a 'tags' key"
+        assert "tags" in result, "The result must have a 'tags' key"
-    assert "updated_at" in result, "The result must have a 'updated_at' key"
+        assert "updated_at" in result, "The result must have a 'updated_at' key"
-    assert "user_id" in result, "The result must have a 'user_id' key"
+        assert "user_id" in result, "The result must have a 'user_id' key"
-    assert "webhook" in result, "The result must have a 'webhook' key"
+        assert "webhook" in result, "The result must have a 'webhook' key"
+
+        content = await flow_file.read_text()
+        Flow.model_validate_json(content)
+    finally:
+        await flow_file.unlink(missing_ok=True)
 
 
 async def test_read_flows(client: AsyncClient, logged_in_headers):
@@ -112,26 +125,35 @@ async def test_update_flow(client: AsyncClient, logged_in_headers):
     response_ = await client.post("api/v1/flows/", json=basic_case, headers=logged_in_headers)
     id_ = response_.json()["id"]
 
+    flow_file = Path(tempfile.tempdir) / f"{uuid.uuid4()!s}.json"
     basic_case["name"] = updated_name
-    response = await client.patch(f"api/v1/flows/{id_}", json=basic_case, headers=logged_in_headers)
+    basic_case["fs_path"] = str(flow_file)
-    result = response.json()
 
-    assert isinstance(result, dict), "The result must be a dictionary"
+    try:
-    assert "data" in result, "The result must have a 'data' key"
+        response = await client.patch(f"api/v1/flows/{id_}", json=basic_case, headers=logged_in_headers)
-    assert "description" in result, "The result must have a 'description' key"
+        result = response.json()
-    assert "endpoint_name" in result, "The result must have a 'endpoint_name' key"
+
-    assert "folder_id" in result, "The result must have a 'folder_id' key"
+        assert isinstance(result, dict), "The result must be a dictionary"
-    assert "gradient" in result, "The result must have a 'gradient' key"
+        assert "data" in result, "The result must have a 'data' key"
-    assert "icon" in result, "The result must have a 'icon' key"
+        assert "description" in result, "The result must have a 'description' key"
-    assert "icon_bg_color" in result, "The result must have a 'icon_bg_color' key"
+        assert "endpoint_name" in result, "The result must have a 'endpoint_name' key"
-    assert "id" in result, "The result must have a 'id' key"
+        assert "folder_id" in result, "The result must have a 'folder_id' key"
-    assert "is_component" in result, "The result must have a 'is_component' key"
+        assert "gradient" in result, "The result must have a 'gradient' key"
-    assert "name" in result, "The result must have a 'name' key"
+        assert "icon" in result, "The result must have a 'icon' key"
-    assert "tags" in result, "The result must have a 'tags' key"
+        assert "icon_bg_color" in result, "The result must have a 'icon_bg_color' key"
-    assert "updated_at" in result, "The result must have a 'updated_at' key"
+        assert "id" in result, "The result must have a 'id' key"
-    assert "user_id" in result, "The result must have a 'user_id' key"
+        assert "is_component" in result, "The result must have a 'is_component' key"
-    assert "webhook" in result, "The result must have a 'webhook' key"
+        assert "name" in result, "The result must have a 'name' key"
-    assert result["name"] == updated_name, "The name must be updated"
+        assert "tags" in result, "The result must have a 'tags' key"
+        assert "updated_at" in result, "The result must have a 'updated_at' key"
+        assert "user_id" in result, "The result must have a 'user_id' key"
+        assert "webhook" in result, "The result must have a 'webhook' key"
+        assert result["name"] == updated_name, "The name must be updated"
+
+        content = await flow_file.read_text()
+        Flow.model_validate_json(content)
+    finally:
+        await flow_file.unlink(missing_ok=True)
 
 
 async def test_create_flows(client: AsyncClient, logged_in_headers):