Yaml
YAML, or Yet-Another-Markup-Language, is often used as a data markup style as it is human readable. In Node-RED, the YAML node is used to convert data between YAML format and JavaScript objects (JSON).
When the input property is JSON the node will produce YAML as output. When the input is JSON, YAML is produced as output.
The node only parses the property key as configured, by default “payload”. When the parsing is successful it replaces the property value.
When no payload is passed into the node it passes the full message on to the next node.
# Examples
# Parsing JSON to YAML
Setting the property to parse in the YAML node is key to parsing. In this case the default payload is used. The YAML node with try and understand what the input format is. When it's JSON, it will send the msg.payload onwards as YAML format.
[{"id":"4481ea08a9fe27e1","type":"inject","z":"7d38803e3d40ee7e","name":"","props":[{"p":"payload"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"foo\":\"bar\"}","payloadType":"json","x":190,"y":220,"wires":[["b31536833d27aee0"]]},{"id":"b31536833d27aee0","type":"yaml","z":"7d38803e3d40ee7e","property":"payload","name":"Parse JSON to YAML","x":400,"y":220,"wires":[["90fed168a9d1a4b5"]]},{"id":"90fed168a9d1a4b5","type":"debug","z":"7d38803e3d40ee7e","name":"Debug: Output YAML","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":640,"y":220,"wires":[]}]# Parsing YAML to JSON
As before, the input is detected by the node itself. When JSON is the input format, it's reformatted to valid YAML.
[{"id":"4481ea08a9fe27e1","type":"inject","z":"7d38803e3d40ee7e","name":"","props":[{"p":"payload"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{\"foo\":\"bar\"}","payloadType":"json","x":190,"y":220,"wires":[["b31536833d27aee0"]]},{"id":"b31536833d27aee0","type":"yaml","z":"7d38803e3d40ee7e","property":"payload","name":"Parse JSON to YAML","x":400,"y":220,"wires":[["90fed168a9d1a4b5"]]},{"id":"90fed168a9d1a4b5","type":"debug","z":"7d38803e3d40ee7e","name":"Debug: Output YAML","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":640,"y":220,"wires":[]}]# Invalid input error handling
When the input is structured wrongly the YAML node will create an error. The error can be caught using the error node.
[{"id":"0fc216b8cebccc25","type":"yaml","z":"7d38803e3d40ee7e","property":"payload","name":"Input invalid","x":370,"y":420,"wires":[[]]},{"id":"a0dc30d8f5225962","type":"inject","z":"7d38803e3d40ee7e","name":"","props":[{"p":"payload"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"foo: \"bar","payloadType":"str","x":180,"y":420,"wires":[["0fc216b8cebccc25"]]},{"id":"c9a3f66e67b41ad4","type":"debug","z":"7d38803e3d40ee7e","name":"Caught error","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":370,"y":500,"wires":[]},{"id":"6e3ba1ebc7beaf81","type":"catch","z":"7d38803e3d40ee7e","name":"","scope":["a0dc30d8f5225962"],"uncaught":false,"x":190,"y":500,"wires":[["c9a3f66e67b41ad4"]]}]Node Documentation
Converts between a YAML formatted string and its JavaScript object representation, in either direction.