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Conditional Logic

Create branching, filtering, and iteration with the Logic node.

Branching lives in the Logic node, not on edges

Edges are always traversed: they have no conditions or relationship types. All conditional routing is done with a Logic node's handles.

Using the Logic Node#

The Logic node provides built-in conditional branching with visual outputs:

If/Else Mode#

  1. Add a Logic node to your workflow
  2. Set mode to "If/Else"
  3. Enter a Jinja2 condition (e.g., payload.temperature > 25)
  4. Connect the if output (blue, bottom-left) to the "true" path
  5. Connect the else output (purple, bottom-right) to the "false" path
code

                ┌─────────────┐
     Input -->  │   Logic     │
                │  (If/Else)  │
                └──────┬──────┘
                       │
              ┌────────┴────────┐
              │                 │
           [if]              [else]
              │                 │
              ▼                 ▼
        [Send Alert]      [Log Normal]

Filter Mode#

Use Filter mode to allow or block events based on a Python condition:

  1. Add a Logic node
  2. Set mode to "Filter"
  3. Write Python code that returns True or False
  4. Events that return True continue; others are dropped

See Logic Node for full documentation.

Branching on Connector Results#

Connectors don't raise an error on a failed call; they return a { success, status, data } envelope (see Connector Output Structure). Branch on it with an If/Else Logic node:

jinja

{{ payload.success }}

Route the if handle (success) and else handle (failure) to different paths.

A raised failure halts the branch

A node that raises a hard failure is logged, marked failed, and its downstream edges are not traversed. There is no "on error" route; that branch simply stops. Most nodes return an envelope instead of raising: the HTTP Request node returns success: false on a 4xx or 5xx and lets the run continue, so route on payload.success rather than expecting a failure. It only raises for statuses you list in its response.error_on_status.

Complex Conditions#

You can use complex Jinja2 expressions in Logic node conditions:

jinja

payload.user.role == 'admin' and steps.auth_check.output_payload.verified
jinja

(steps.api_call.output_payload | jsonpath('$.items[?(@.active == true)]')) | length > 0

Best Practices#

  1. Branch with Logic nodes - all conditional routing happens here, never on edges
  2. Use clear, descriptive conditions
  3. Test both branches
  4. Handle edge cases (null values, missing fields)
  5. Use the default filter for safe access: (payload.value | default(0)) > 25

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