Switch

Route messages based on their property values or sequence position.

Inputs

Just the msg object required, no specific keys are used.

Outputs

Multiple output ports can be added, based on the number of conditions being switched between.

Details

When a message arrives, the node will evaluate each of the defined rules and forward the message to the corresponding outputs of any matching rules.

Optionally, the node can be set to stop evaluating rules once it finds one that matches.

The rules can be evaluated against an individual message property, a flow or global context property, environment variable or the result of a JSONata expression.

Rules

There are four types of rule:

1. Value rules are evaluated against the configured property

2. Sequence rules can be used on message sequences, such as those generated by the Split node

3. A JSONata Expression can be provided that will be evaluated against the whole message and will match if the expression returns a true value.

4. An Otherwise rule can be used to match if none of the preceeding rules have matched.

Notes

The is true/false and is null rules perform strict comparisons against those types. They do not convert between types.

The is empty and is not empty rules can be used to test the length of Strings, Arrays and Buffers, or the number of properties an Object has. Neither rule will pass if the property being tested has a boolean, null or undefined value.

Handling message sequences

By default, the node does not modify the msg.parts property of messages that are part of a sequence.

The recreate message sequences option can be enabled to generate new message sequences for each rule that matches. In this mode, the node will buffer the entire incoming sequence before sending the new sequences on. The runtime setting nodeMessageBufferMaxLength can be used to limit how many messages nodes will buffer.