Condition nodes

Condition nodes add branching logic to a workflow. A condition node defines one or more outlets, each with a JQ expression. When the workflow reaches the node, Port evaluates the expressions and continues down the path of the first outlet whose expression is true.

Like input nodes, condition nodes branch the workflow. Unlike input nodes, they don't pause the run or require any human interaction - the decision is made instantly based on data already in the workflow run context.

How it works

1. The workflow reaches the condition node.
2. Port evaluates each outlet's expression in the order they're defined, against the current workflow run context.
3. The workflow continues down the path of the first outlet whose expression evaluates to true. Remaining outlets are not evaluated.
4. If none of the outlets evaluate to true, the workflow continues down the node's fallback connection, if one is defined. See connections.
5. If no outlet matches and no fallback connection is defined, that branch of the workflow ends without an error.

Expressions must evaluate to a boolean

If an outlet's expression fails to evaluate (for example, due to invalid JQ syntax or a reference to a field that doesn't exist), the entire node fails and the workflow run fails. Make sure your expressions evaluate safely against the data you expect to be present.

Example

{
  "identifier": "check-environment",
  "title": "Check Environment",
  "config": {
    "type": "CONDITION",
    "outlets": [
      {
        "identifier": "production",
        "title": "Production",
        "expression": ".outputs.trigger.environment == \"production\""
      },
      {
        "identifier": "staging",
        "title": "Staging",
        "expression": ".outputs.trigger.environment == \"staging\""
      }
    ]
  }
}

Configuration

A condition node is defined by a config object with "type": "CONDITION" and the following fields:

Field	Required	Description
type	Yes	Must be "CONDITION".
outlets	Yes	The ordered list of branches the node can continue on. See outlets below.

Outlets

Each outlet has the following fields:

Outlet order and uniqueness

Outlets are evaluated in the order they're defined, and the first match wins - so put more specific conditions before more general ones. Each outlet's identifier must be unique within the node.

Field	Required	Description
identifier	Yes	A unique identifier for the outlet. Connections reference this value.
title	No	A human-readable name for the outlet, shown in the graph.
expression	Yes	A JQ expression evaluated against the workflow run context. The outlet is taken when this evaluates to true.
statusLabel	No	A label applied to the node run when this outlet is taken. Has a text field (supports JQ) and an optional variant of success or alert.
workflowStatusLabel	No	Same as statusLabel, but applied to the entire workflow run.

Expression syntax

Unlike other node fields, expression is a raw JQ expression, not a {{ }} template. Write .outputs.trigger.environment == "production", not {{ .outputs.trigger.environment == "production" }}.

Connections

Connections from a condition node must specify which outlet they're connected to, using sourceOutletIdentifier. You can also mark one connection as the fallback (shown as else in the workflow builder), which the workflow takes when no outlet's expression matches:

{
  "connections": [
    {
      "sourceIdentifier": "check-environment",
      "targetIdentifier": "production-deploy",
      "sourceOutletIdentifier": "production"
    },
    {
      "sourceIdentifier": "check-environment",
      "targetIdentifier": "staging-deploy",
      "sourceOutletIdentifier": "staging"
    },
    {
      "sourceIdentifier": "check-environment",
      "targetIdentifier": "default-deploy",
      "fallback": true
    }
  ]
}

Each sourceOutletIdentifier must reference a valid outlet identifier on the node, and a node can have at most one fallback connection.

Outputs

When an outlet matches, a condition node produces the following output, which subsequent nodes can reference through data flow:

• selectedOutlet.identifier - the identifier of the outlet the node continued on.
• selectedOutlet.expression - the expression of the outlet that matched.

When the workflow continues down the fallback connection instead, selectedOutlet is not set.

For example, to branch further on the selected outlet in a downstream node:

{{ .outputs["check-environment"].selectedOutlet.identifier }}

Related links

• Input nodes - Branch a workflow based on human responses.
• Data flow - Pass outputs between nodes.