Flows Manager

14 min

The flows module manages Node-RED flow instances on Litmus Edge.

Note: For reading or modifying the internal content of a flow (nodes, wires, tabs), use the Node-RED API directly. The SDK only covers the flows-manager service (lifecycle management).

Imports

from litmussdk import flows

Common Operations (3.x and 4.0.x)

Listing Flows

all_flows = flows.list_flows()  # list[dict]
# Each entry: {id, name, memory_limit, secret, tabs: [...]}

# Find a flow by name
flow = next((f for f in flows.list_flows() if f["name"] == "My Flow"), None)

Creating a Flow

Creates a stopped, empty flow. Fails if a flow with the same name already exists.

flow = flows.create_flow(
    name="My Flow",
    secret="my-secret",
    memory_limit=256,
)
flow_id = flow["id"]

Starting and Stopping

flows.start_flow(flow_id)
flows.stop_flow(flow_id)

Calling start_flow on a running flow (or stop_flow on a stopped flow) will raise an error.

Updating a Flow

flows.update_flow(
    flow_id=flow_id,
    name="Renamed Flow",
    memory_limit=512,
)

Removing a Flow

Destroys the flow and all its internal tabs.

flows.remove_flow(flow_id)

4.0.x-Only Operations

These functions raise UnsupportedVersionError when called against a 3.x device.

Download Flow File

Returns the raw .json flow definition as bytes.

content: bytes = flows.download_flow_file(flow_id)

# Save to disk
with open("my_flow.json", "wb") as f:
    f.write(content)

2.6.0 fix: prior versions of the SDK silently UTF-8-decoded the response, which corrupted binary content. As of 2.6.0, download_flow_file and download_flow_logs route through a binary-safe code path and return real bytes. Upgrade if you saw mangled output or the literal string "None" before.

Download Flow Logs

logs: bytes = flows.download_flow_logs(flow_id)

Delete Flow Artifacts

Clean up individual flow artifacts without deleting the flow itself:

flows.delete_flow_flows_json(flow_id)     # removes flows.json
flows.delete_flow_credentials(flow_id)   # removes credentials file
flows.delete_flow_logs(flow_id)          # removes log files
flows.delete_flow_node_modules(flow_id)  # removes node_modules