while component: Conditional loop node. It executes the target node or rule chain repeatedly as long as the specified condition is met.

Configuration

Field	Type	Description	Default
condition	string	The loop condition expression using el expression language. E.g., msg.count==nil || msg.count < 5.
do	string	The Node ID or Sub-Rule Chain ID to execute in each iteration.

Relation Type

• Success: After the loop finishes, the message is passed along the Success chain.
• Failure: If an error occurs during expression evaluation or iteration, the message is passed along the Failure chain.

Execution Result

Returns the result of the last iteration. The result of the previous iteration is used as input for the next iteration.

Iteration Context Variables

During iteration, the component sets the following metadata variables:

• _loopIndex: Current iteration index (starting from 0).

Breaking the Loop

If the message metadata contains _break with value true during iteration, the loop terminates immediately.

Configuration Example

{
  "id": "s1",
  "type": "while",
  "name": "While Loop",
  "configuration": {
    "condition": "msg.count==nil || msg.count < 5",
    "do": "s2"
  }
}