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API examples

This page provides examples and practices for managing Langflow using the Langflow API.

The Langflow API's OpenAPI spec can be viewed and tested at your Langflow deployment's docs endpoint. For example, http://127.0.0.1:7860/docs.

Export values​

You might find it helpful to set the following environment variables in your terminal.

The examples in this guide use environment variables for these values.

  • Export your Langflow URL in your terminal. Langflow starts by default at http://127.0.0.1:7860.

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export LANGFLOW_URL="http://127.0.0.1:7860"

  • Export the flow-id in your terminal. The flow-id is found in the Publish pane or in the flow's URL.

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export FLOW_ID="359cd752-07ea-46f2-9d3b-a4407ef618da"

  • Export the project-id in your terminal. To find your project ID, call the Langflow /api/v1/projects/ endpoint for a list of projects.

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curl -X GET \
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"$LANGFLOW_URL/api/v1/projects/" \
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-H "accept: application/json"

  • Export the project-id as an environment variable.

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export project_ID="1415de42-8f01-4f36-bf34-539f23e47466"

  • Export the Langflow API key as an environment variable. To create a Langflow API key, run the following command in the Langflow CLI.

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langflow api-key

Export the generated API key as an environment variable.


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export LANGFLOW_API_KEY="sk-..."

Base​

Use the base Langflow API to run your flow and retrieve configuration information.

Get all components​

This operation returns a dictionary of all Langflow components.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/all" \
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-H "accept: application/json"

Run flow​

Execute a specified flow by ID or name. The flow is executed as a batch, but LLM responses can be streamed.

This example runs a Basic Prompting flow with a given flow_id and passes a JSON object as the input value.

The parameters are passed in the request body. In this example, the values are the default values.


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curl -X POST \
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"$LANGFLOW_URL/api/v1/run/$FLOW_ID" \
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-H "Content-Type: application/json" \
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-d '{
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"input_value": "Tell me about something interesting!",
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"session_id": "chat-123",
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"input_type": "chat",
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"output_type": "chat",
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"output_component": "",
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"tweaks": null
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}'

To stream LLM token responses, append the ?stream=true query parameter to the request. LLM chat responses are streamed back as token events until the end event closes the connection.


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curl -X POST \
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"$LANGFLOW_URL/api/v1/run/$FLOW_ID?stream=true" \
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-H "accept: application/json" \
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-H "Content-Type: application/json" \
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-d '{
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"message": "Tell me something interesting!",
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"session_id": "chat-123"
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}'

This result is abbreviated, but illustrates where the end event completes the LLM's token streaming response.

Run endpoint headers and parameters​

Parameters can be passed to the /run endpoint in three ways:

  • URL path: flow_id as part of the endpoint path
  • Query string: stream parameter in the URL
  • Request body: JSON object containing the remaining parameters

Headers

HeaderInfoExample
Content-TypeRequired. Specifies the JSON format."application/json"
acceptRequired. Specifies the response format."application/json"
x-api-keyOptional. Required only if authentication is enabled."sk-..."

Parameters

ParameterTypeInfo
flow_idUUID/stringRequired. Part of URL: /run/{flow_id}
streambooleanOptional. Query parameter: /run/{flow_id}?stream=true
input_valuestringOptional. JSON body field. Main input text/prompt. Default: null
input_typestringOptional. JSON body field. Input type ("chat" or "text"). Default: "chat"
output_typestringOptional. JSON body field. Output type ("chat", "any", "debug"). Default: "chat"
output_componentstringOptional. JSON body field. Target component for output. Default: ""
tweaksobjectOptional. JSON body field. Component adjustments. Default: null
session_idstringOptional. JSON body field. Conversation context ID. Default: null

Example request


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curl -X POST \
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"http://$LANGFLOW_URL/api/v1/run/$FLOW_ID?stream=true" \
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-H "Content-Type: application/json" \
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-H "accept: application/json" \
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-H "x-api-key: sk-..." \
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-d '{
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"input_value": "Tell me a story",
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"input_type": "chat",
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"output_type": "chat",
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"output_component": "chat_output",
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"session_id": "chat-123",
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"tweaks": {
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"component_id": {
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"parameter_name": "value"
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}
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}
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}'

Webhook run flow​

The webhook endpoint triggers flow execution with an HTTP POST request.

When a Webhook component is added to the workspace, a new Webhook cURL tab becomes available in the API pane that contains an HTTP POST request for triggering the webhook component, similar to the call in this example.

To test the Webhook component in your flow, see the Webhook component.


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curl -X POST \
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"$LANGFLOW_URL/api/v1/webhook/$FLOW_ID" \
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-H "Content-Type: application/json" \
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-d '{"data": "example-data"}'

Process​

info

This endpoint is deprecated. Use the /run endpoint instead.

Predict​

info

This endpoint is deprecated. Use the /run endpoint instead.

Get task status​

Get the status of a task.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/task/TASK_ID" \
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-H "accept: application/json"

Create upload file (Deprecated)​

info

This endpoint is deprecated. Use the /file endpoint instead.

Get version​

Get the version of the Langflow API.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/version" \
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-H "accept: application/json"

Get config​

Retrieve the Langflow configuration information.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/config" \
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-H "accept: application/json"

Build​

Use the /build endpoint to build vertices and flows, and execute those flows with streaming event responses.

The /build endpoint offers additional configuration for running flows.

For a simpler execution of your flows, use the /run endpoint instead.

Build flow​

important

This endpoint is meant to be used by the frontend and is not optimized for external use. To run your flow, use the /run endpoint instead.

This endpoint builds and executes a flow, returning a job ID that can be used to stream execution events.

  1. Send a POST request to the /build/{flow_id}/flow endpoint.

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curl -X POST \
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"$LANGFLOW_URL/api/v1/build/$FLOW_ID/flow" \
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-H "accept: application/json" \
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-H "Content-Type: application/json" \
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-d '{
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"inputs": {
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"input_value": "Tell me a story"
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}
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}'

  1. After receiving a job ID from the build endpoint, use the /build/{job_id}/events endpoint to stream the execution results:

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curl -X GET \
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"$LANGFLOW_URL/api/v1/build/123e4567-e89b-12d3-a456-426614174000/events" \
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-H "accept: application/json"

The events endpoint accepts an optional stream query parameter which defaults to true. To disable streaming and get all events at once, set stream to false.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/build/123e4567-e89b-12d3-a456-426614174000/events?stream=false" \
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-H "accept: application/json"

Build endpoint headers and parameters​

Headers

HeaderInfoExample
Content-TypeRequired. Specifies the JSON format."application/json"
acceptRequired. Specifies the response format."application/json"
x-api-keyOptional. Required only if authentication is enabled."sk-..."

The /build/{flow_id}/flow endpoint accepts the following parameters in its request body:

Parameters

ParameterTypeDescription
inputsobjectOptional. Input values for flow components.
dataobjectOptional. Flow data to override stored configuration.
filesarray[string]Optional. List of file paths to use.
stop_component_idstringOptional. ID of the component where the execution should stop.
start_component_idstringOptional. ID of the component where the execution should start.
log_buildsbooleanOptional. Control build logging. Default: true.

Configure the build endpoint​

The /build endpoint accepts optional values for start_component_id and stop_component_id to control where the flow run starts and stops. Setting stop_component_id for a component triggers the same behavior as clicking the Play button on that component, where all dependent components leading up to that component are also run. For example, to stop flow execution at the Open AI model component, run the following command:


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curl -X POST \
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"$LANGFLOW_URL/api/v1/build/$FLOW_ID/flow" \
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-H "accept: application/json" \
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-H "Content-Type: application/json" \
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-H "x-api-key: $LANGFLOW_API_KEY" \
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-d '{"stop_component_id": "OpenAIModel-Uksag"}'

The /build endpoint also accepts inputs for data directly, instead of using the values stored in the Langflow database. This is useful for running flows without having to pass custom values through the UI.


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curl -X POST \
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"$LANGFLOW_URL/api/v1/build/$FLOW_ID/flow" \
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-H "accept: application/json" \
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-H "Content-Type: application/json" \
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-d '{
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"data": {
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"nodes": [],
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"edges": []
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},
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"inputs": {
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"input_value": "Your custom input here",
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"session": "session_id"
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}
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}'

Files​

Use the /files endpoint to add or delete files between your local machine and Langflow.

There are /v1 and /v2 versions of the /files endpoints. The v2/files version offers several improvements over /v1:

  • In v1, files are organized by flow_id. In v2, files are organized by user_id. This means files are accessed based on user ownership, and not tied to specific flows. You can upload a file to Langflow one time, and use it with multiple flows.
  • In v2, files are tracked in the Langflow database, and can be added or deleted in bulk, instead of one by one.
  • Responses from the /v2 endpoint contain more descriptive metadata.
  • The v2 endpoints require authentication by an API key or JWT.

Files/V1 endpoints​

Use the /files endpoint to add or delete files between your local machine and Langflow.

  • In v1, files are organized by flow_id.
  • In v2, files are organized by user_id and tracked in the Langflow database, and can be added or deleted in bulk, instead of one by one.

Upload file (v1)​

Upload a file to the v1/files/upload/<YOUR-FLOW-ID> endpoint of your flow. Replace FILE_NAME with the uploaded file name.


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curl -X POST \
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"$LANGFLOW_URL/api/v1/files/upload/$FLOW_ID" \
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-H "accept: application/json" \
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-H "Content-Type: multipart/form-data" \
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-F "file=@FILE_NAME.txt"

Upload image files (v1)​

Send image files to the Langflow API for AI analysis.

The default file limit is 100 MB. To configure this value, change the LANGFLOW_MAX_FILE_SIZE_UPLOAD environment variable. For more information, see Supported environment variables.

  1. To send an image to your flow with the API, POST the image file to the v1/files/upload/<YOUR-FLOW-ID> endpoint of your flow. Replace FILE_NAME with the uploaded file name.

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curl -X POST "$LANGFLOW_URL/api/v1/files/upload/a430cc57-06bb-4c11-be39-d3d4de68d2c4" \
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-H "Content-Type: multipart/form-data" \
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-F "file=@FILE_NAME.png"

The API returns the image file path in the format "file_path":"<YOUR-FLOW-ID>/<TIMESTAMP>_<FILE-NAME>"}.


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{
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"flowId": "a430cc57-06bb-4c11-be39-d3d4de68d2c4",
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"file_path": "a430cc57-06bb-4c11-be39-d3d4de68d2c4/2024-11-27_14-47-50_image-file.png"
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}

  1. Post the image file to the Chat Input component of a Basic prompting flow. Pass the file path value as an input in the Tweaks section of the curl call to Langflow. To find your Chat input component's ID, use the

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curl -X POST \
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"$LANGFLOW_URL/api/v1/run/a430cc57-06bb-4c11-be39-d3d4de68d2c4?stream=false" \
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-H 'Content-Type: application/json'\
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-d '{
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"output_type": "chat",
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"input_type": "chat",
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"tweaks": {
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"ChatInput-b67sL": {
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"files": "a430cc57-06bb-4c11-be39-d3d4de68d2c4/2024-11-27_14-47-50_image-file.png",
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"input_value": "what do you see?"
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}
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}}'

Your chatbot describes the image file you sent.


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"text": "This flowchart appears to represent a complex system for processing financial inquiries using various AI agents and tools. Here's a breakdown of its components and how they might work together..."

List files (v1)​

List all files associated with a specific flow.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/files/list/$FLOW_ID" \
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-H "accept: application/json"

Download file (v1)​

Download a specific file from a flow.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/files/download/$FLOW_ID/2024-12-30_15-19-43_your_file.txt" \
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-H "accept: application/json" \
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--output downloaded_file.txt

Delete file (v1)​

Delete a specific file from a flow.


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curl -X DELETE \
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"$LANGFLOW_URL/api/v1/files/delete/$FLOW_ID/2024-12-30_15-19-43_your_file.txt" \
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-H "accept: application/json"

Files/V2 endpoints​

In v2, files are organized by user_id and tracked in the Langflow database, and can be added or deleted in bulk, instead of one by one. The v2 endpoints require authentication by an API key or JWT. To create a Langflow API key and export it as an environment variable, see Export values.

Upload file (v2)​

Upload a file to your user account. The file can be used across multiple flows.

The file is uploaded in the format USER_ID/FILE_ID.FILE_EXTENSION, such as 07e5b864-e367-4f52-b647-a48035ae7e5e/d44dc2e1-9ae9-4cf6-9114-8d34a6126c94.pdf.

To retrieve your current user_id, call the /whoami endpoint.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/users/whoami" \
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-H "accept: application/json"

Result:


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{"id":"07e5b864-e367-4f52-b647-a48035ae7e5e","username":"langflow","profile_image":null,"store_api_key":null,"is_active":true,"is_superuser":true,"create_at":"2025-05-08T17:59:07.855965","updated_at":"2025-05-28T19:00:42.556460","last_login_at":"2025-05-28T19:00:42.554338","optins":{"github_starred":false,"dialog_dismissed":true,"discord_clicked":false,"mcp_dialog_dismissed":true}}

In the POST request to v2/files, replace @FILE_NAME.EXTENSION with the uploaded file name and its extension. You must include the ampersand (@) in the request to instruct curl to upload the contents of the file, not the string FILE_NAME.EXTENSION.


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curl -X POST \
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"$LANGFLOW_URL/api/v2/files" \
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-H "accept: application/json" \
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-H "Content-Type: multipart/form-data" \
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-H "x-api-key: $LANGFLOW_API_KEY" \
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-F "file=@FILE_NAME.EXTENSION"

The file is uploaded in the format USER_ID/FILE_ID.FILE_EXTENSION, and the API returns metadata about the uploaded file:


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{
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"id":"d44dc2e1-9ae9-4cf6-9114-8d34a6126c94",
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"name":"engine_manual",
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"path":"07e5b864-e367-4f52-b647-a48035ae7e5e/d44dc2e1-9ae9-4cf6-9114-8d34a6126c94.pdf",
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"size":851160,
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"provider":null
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}

Send files to your flows (v2)​

Send a file to your flow for analysis using the File component and the API. Your flow must contain a File component to receive the file.

The default file limit is 100 MB. To configure this value, change the LANGFLOW_MAX_FILE_SIZE_UPLOAD environment variable. For more information, see Supported environment variables.

  1. To send an image to your flow with the API, POST the image file to the /api/v2/files endpoint. Replace FILE_NAME with the uploaded file name. This is the same step described in Upload file (v2), but since you need the filename to upload to your flow, it is included here.

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curl -X POST \
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"$LANGFLOW_URL/api/v2/files" \
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-H "accept: application/json" \
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-H "Content-Type: multipart/form-data" \
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-H "x-api-key: $LANGFLOW_API_KEY" \
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-F "file=@FILE_NAME.EXTENSION"

The file is uploaded in the format USER_ID/FILE_ID.FILE_EXTENSION, and the API returns metadata about the uploaded file:


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{
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"id":"d44dc2e1-9ae9-4cf6-9114-8d34a6126c94",
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"name":"engine_manual",
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"path":"07e5b864-e367-4f52-b647-a48035ae7e5e/d44dc2e1-9ae9-4cf6-9114-8d34a6126c94.pdf",
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"size":851160,
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"provider": null
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}

  1. To use this file in your flow, add a File component to load a file into the flow.
  2. To load the file into your flow, send it to the File component. To retrieve the File component's full name with the UUID attached, call the Read flow endpoint, and then include your File component and the file path as a tweak with the /v1/run POST request. In this example, the file uploaded to /v2/files is included with the /v1/run POST request.

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curl --request POST \
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--url "$LANGFLOW_URL/api/v1/run/$FLOW_ID" \
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--header "Content-Type: application/json" \
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--data '{
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"input_value": "what do you see?",
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"output_type": "chat",
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"input_type": "text",
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"tweaks": {
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"File-1olS3": {
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"path": [
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"07e5b864-e367-4f52-b647-a48035ae7e5e/3a290013-fe1e-4d3d-a454-cacae81288f3.pdf"
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]
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}
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}
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}'

Result:


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"text":"This document provides important safety information and instructions for selecting, installing, and operating Briggs & Stratton engines. It includes warnings and guidelines to prevent injury, fire, or damage, such as choosing the correct engine model, proper installation procedures, safe fuel handling, and correct engine operation. The document emphasizes following all safety precautions and using authorized parts to ensure safe and effective engine use."

List files (v2)​

List all files associated with your user account.


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curl -X GET \
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"$LANGFLOW_URL/api/v2/files" \
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-H "accept: application/json" \
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-H "x-api-key: $LANGFLOW_API_KEY"

Download file (v2)​

Download a specific file by its ID and file extension.

tip

You must specify the file type you expect in the --output value.


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curl -X GET \
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"$LANGFLOW_URL/api/v2/files/c7b22c4c-d5e0-4ec9-af97-5d85b7657a34" \
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-H "accept: application/json" \
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-H "x-api-key: $LANGFLOW_API_KEY" \
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--output downloaded_file.txt

Edit file name (v2)​

Change a file name.


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curl -X PUT \
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"$LANGFLOW_URL/api/v2/files/$FILE_ID?name=new_file_name" \
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-H "accept: application/json" \
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-H "x-api-key: $LANGFLOW_API_KEY"

Delete file (v2)​

Delete a specific file by its ID.


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curl -X DELETE \
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"$LANGFLOW_URL/api/v2/files/$FILE_ID" \
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-H "accept: application/json" \
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-H "x-api-key: $LANGFLOW_API_KEY"

Delete all files (v2)​

Delete all files associated with your user account.


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curl -X DELETE \
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"$LANGFLOW_URL/api/v2/files" \
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-H "accept: application/json" \
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-H "x-api-key: $LANGFLOW_API_KEY"

Flows​

Use the /flows endpoint to create, read, update, and delete flows.

Create flow​

Create a new flow.


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curl -X POST \
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"$LANGFLOW_URL/api/v1/flows/" \
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-H "accept: application/json" \
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-H "Content-Type: application/json" \
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-d '{
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"name": "string2",
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"description": "string",
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"icon": "string",
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"icon_bg_color": "#FF0000",
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"gradient": "string",
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"data": {},
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"is_component": false,
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"updated_at": "2024-12-30T15:48:01.519Z",
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"webhook": false,
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"endpoint_name": "string",
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"tags": [
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"string"
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]
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}'

Read flows​

Retrieve a list of flows with pagination support.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/flows/?remove_example_flows=false&components_only=false&get_all=true&header_flows=false&page=1&size=50" \
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-H "accept: application/json"

To retrieve only the flows from a specific project, pass project_id in the query string.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/flows/?remove_example_flows=true&components_only=false&get_all=false&project_id=$PROJECT_ID&header_flows=false&page=1&size=1" \
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-H "accept: application/json"

Read flow​

Read a specific flow by its ID.


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curl -X GET \
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"$LANGFLOW_URL/api/v1/flows/$FLOW_ID" \
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-H "accept: application/json"

Update flow​

Update an existing flow by its ID.

This example changes the value for endpoint_name from a random UUID to my_new_endpoint_name.


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curl -X PATCH \
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"$LANGFLOW_URL/api/v1/flows/$FLOW_ID" \
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-H "accept: application/json" \
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-H "Content-Type: application/json" \
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-d '{
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"name": "string",
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"description": "string",
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"data": {},
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"project_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
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"project_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
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"endpoint_name": "my_new_endpoint_name",
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"locked": true
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}'

Delete flow​

Delete a specific flow by its ID.


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curl -X DELETE \
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"$LANGFLOW_URL/api/v1/flows/$FLOW_ID" \
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-H "accept: application/json"

Create flows​

Create multiple new flows.


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curl -X POST \
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"$LANGFLOW_URL/api/v1/flows/batch/" \
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-H "accept: application/json" \
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-H "Content-Type: application/json" \
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-d '{
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"flows": [
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{
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"name": "string",
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"description": "string",
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"icon": "string",
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"icon_bg_color": "string",
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"gradient": "string",
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"data": {},
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"is_component": false,
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"updated_at": "2024-12-30T18:36:02.737Z",
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"webhook": false,
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"endpoint_name": "string",
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"tags": [
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"string"
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],
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"locked": false,
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"user_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
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"project_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6"
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"project_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6"
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},
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{
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"name": "string",
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"description": "string",
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"icon": "string",
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"icon_bg_color": "string",
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"gradient": "string",
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"data": {},
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"is_component": false,
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"updated_at": "2024-12-30T18:36:02.737Z",
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"webhook": false,
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"endpoint_name": "string",
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"tags": [
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"string"
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],
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"locked": false,
_46
"user_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
_46
"project_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6"
_46
"project_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6"
_46
}
_46
]
_46
}'

Upload flows​

Upload flows from a file.

This example uploads a local file named agent-with-astra-db-tool.json.


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curl -X POST \
_10
"$LANGFLOW_URL/api/v1/flows/upload/?project_id=$PROJECT_ID" \
_10
-H "accept: application/json" \
_10
-H "Content-Type: multipart/form-data" \
_10
-F "file=@agent-with-astra-db-tool.json;type=application/json"

To specify a target project for the flow, include the query parameter project_id. The target project_id must already exist before uploading a flow. Call the /api/v1/projects/ endpoint for a list of available projects. To specify a target project for the flow, include the query parameter project_id. The target project_id must already exist before uploading a flow. Call the /api/v1/projects/ endpoint for a list of available projects.


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curl -X POST \
_10
"$LANGFLOW_URL/api/v1/flows/upload/?project_id=$PROJECT_ID" \
_10
-H "accept: application/json" \
_10
-H "Content-Type: multipart/form-data" \
_10
-F "file=@agent-with-astra-db-tool.json;type=application/json"

Download all flows​

Download all flows as a ZIP file.

This endpoint downloads a ZIP file containing flows for all flow-id values listed in the command's body.


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curl -X POST \
_10
"$LANGFLOW_URL/api/v1/flows/download/" \
_10
-H "accept: application/json" \
_10
-H "Content-Type: application/json" \
_10
-d '[
_10
"e1e40c77-0541-41a9-88ab-ddb3419398b5",
_10
"92f9a4c5-cfc8-4656-ae63-1f0881163c28"
_10
]' \
_10
--output langflow-flows.zip

Read basic examples​

Retrieve a list of basic example flows.


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curl -X GET \
_10
"$LANGFLOW_URL/api/v1/flows/basic_examples/" \
_10
-H "accept: application/json"

Projects​

Use the /projects endpoint to create, read, update, and delete projects.

Projects store your flows and components.

Read projects​

Get a list of Langflow projects.


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curl -X GET \
_10
"$LANGFLOW_URL/api/v1/projects/" \
_10
-H "accept: application/json"

Create project​

Create a new project.


_10
curl -X POST \
_10
"$LANGFLOW_URL/api/v1/projects/" \
_10
-H "Content-Type: application/json" \
_10
-d '{
_10
"name": "new_project_name",
_10
"description": "string",
_10
"components_list": [],
_10
"flows_list": []
_10
}'

To add flows and components at project creation, retrieve the components_list and flows_list values from the /api/v1/store/components and /api/v1/flows/read endpoints and add them to the request body.

Adding a flow to a project moves the flow from its previous location. The flow is not copied.


_14
curl -X POST \
_14
"$LANGFLOW_URL/api/v1/projects/" \
_14
-H "accept: application/json" \
_14
-H "Content-Type: application/json" \
_14
-d '{
_14
"name": "new_project_name",
_14
"description": "string",
_14
"components_list": [
_14
"3fa85f64-5717-4562-b3fc-2c963f66afa6"
_14
],
_14
"flows_list": [
_14
"3fa85f64-5717-4562-b3fc-2c963f66afa6"
_14
]
_14
}'

Read project​

Retrieve details of a specific project.

To find the UUID of your project, call the read projects endpoint.


_10
curl -X GET \
_10
"$LANGFLOW_URL/api/v1/projects/$PROJECT_ID" \
_10
-H "accept: application/json"

Update project​

Update the information of a specific project with a PATCH request.

Each PATCH request updates the project with the values you send. Only the fields you include in your request are updated. If you send the same values multiple times, the update is still processed, even if the values are unchanged.


_14
curl -X PATCH \
_14
"$LANGFLOW_URL/api/v1/projects/b408ddb9-6266-4431-9be8-e04a62758331" \
_14
-H "accept: application/json" \
_14
-d '{
_14
"name": "string",
_14
"description": "string",
_14
"parent_id": "3fa85f64-5717-4562-b3fc-2c963f66afa6",
_14
"components": [
_14
"3fa85f64-5717-4562-b3fc-2c963f66afa6"
_14
],
_14
"flows": [
_14
"3fa85f64-5717-4562-b3fc-2c963f66afa6"
_14
]
_14
}'

Delete project​

Delete a specific project.


_10
curl -X DELETE \
_10
"$LANGFLOW_URL/api/v1/projects/$PROJECT_ID" \
_10
-H "accept: */*"

Download project​

Download all flows from a project as a zip file.

The --output flag is optional.


_10
curl -X GET \
_10
"$LANGFLOW_URL/api/v1/projects/download/b408ddb9-6266-4431-9be8-e04a62758331" \
_10
-H "accept: application/json" \
_10
--output langflow-project.zip

Upload project​

Upload a project to Langflow.


_10
curl -X POST \
_10
"$LANGFLOW_URL/api/v1/projects/upload/" \
_10
-H "accept: application/json" \
_10
-H "Content-Type: multipart/form-data" \
_10
-F "file=@20241230_135006_langflow_flows.zip;type=application/zip"

Logs​

Retrieve logs for your Langflow flow.

This endpoint requires log retrieval to be enabled in your Langflow application.

To enable log retrieval, include these values in your .env file:


_10
LANGFLOW_ENABLE_LOG_RETRIEVAL=true
_10
LANGFLOW_LOG_RETRIEVER_BUFFER_SIZE=10000
_10
LANGFLOW_LOG_LEVEL=DEBUG

For log retrieval to function, LANGFLOW_LOG_RETRIEVER_BUFFER_SIZE needs to be greater than 0. The default value is 10000.

Start Langflow with this .env:


_10
uv run langflow run --env-file .env

Stream logs​

Stream logs in real-time using Server-Sent Events (SSE).


_10
curl -X GET \
_10
"$LANGFLOW_URL/logs-stream" \
_10
-H "accept: text/event-stream"

Retrieve logs with optional parameters​

Retrieve logs with optional query parameters.

  • lines_before: The number of logs before the timestamp or the last log.
  • lines_after: The number of logs after the timestamp.
  • timestamp: The timestamp to start getting logs from.

The default values for all three parameters is 0. With these values, the endpoint returns the last 10 lines of logs.


_10
curl -X GET \
_10
"$LANGFLOW_URL/logs?lines_before=0&lines_after=0&timestamp=0" \
_10
-H "accept: application/json"

Monitor​

Use the /monitor endpoint to monitor and modify messages passed between Langflow components, vertex builds, and transactions.

Get Vertex builds​

Retrieve Vertex builds for a specific flow.


_10
curl -X GET \
_10
"$LANGFLOW_URL/api/v1/monitor/builds?flow_id=$FLOW_ID" \
_10
-H "accept: application/json"

Delete Vertex builds​

Delete Vertex builds for a specific flow.


_10
curl -X DELETE \
_10
"$LANGFLOW_URL/api/v1/monitor/builds?flow_id=$FLOW_ID" \
_10
-H "accept: */*"

Get messages​

Retrieve messages with optional filters.


_10
curl -X GET \
_10
"$LANGFLOW_URL/api/v1/monitor/messages" \
_10
-H "accept: application/json"

You can filter messages by flow_id, session_id, sender, and sender_name. Results can be ordered with the order_by query string.

This example retrieves messages sent by Machine and AI in a given chat session (session_id) and orders the messages by timestamp.


_10
curl -X GET \
_10
"$LANGFLOW_URL/api/v1/monitor/messages?flow_id=$FLOW_ID&session_id=01ce083d-748b-4b8d-97b6-33adbb6a528a&sender=Machine&sender_name=AI&order_by=timestamp" \
_10
-H "accept: application/json"

Delete messages​

Delete specific messages by their IDs.

This example deletes the message retrieved in the previous Get messages example.


_10
curl -v -X DELETE \
_10
"$LANGFLOW_URL/api/v1/monitor/messages" \
_10
-H "accept: */*" \
_10
-H "Content-Type: application/json" \
_10
-d '["MESSAGE_ID_1", "MESSAGE_ID_2"]'

Update message​

Update a specific message by its ID.

This example updates the text value of message 3ab66cc6-c048-48f8-ab07-570f5af7b160.


_10
curl -X PUT \
_10
"$LANGFLOW_URL/api/v1/monitor/messages/3ab66cc6-c048-48f8-ab07-570f5af7b160" \
_10
-H "accept: application/json" \
_10
-H "Content-Type: application/json" \
_10
-d '{
_10
"text": "testing 1234"
_10
}'

Update session ID​

Update the session ID for messages.

This example updates the session_ID value 01ce083d-748b-4b8d-97b6-33adbb6a528a to different_session_id.


_10
curl -X PATCH \
_10
"$LANGFLOW_URL/api/v1/monitor/messages/session/01ce083d-748b-4b8d-97b6-33adbb6a528a?new_session_id=different_session_id" \
_10
-H "accept: application/json"

Delete messages by session​

Delete all messages for a specific session.


_10
curl -X DELETE \
_10
"$LANGFLOW_URL/api/v1/monitor/messages/session/different_session_id_2" \
_10
-H "accept: */*"

Get transactions​

Retrieve all transactions (interactions between components) for a specific flow.


_10
curl -X GET \
_10
"$LANGFLOW_URL/api/v1/monitor/transactions?flow_id=$FLOW_ID&page=1&size=50" \
_10
-H "accept: application/json"

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