This flow exemplifies how to split an array to separate messages, manipulate them individually, and the reconstruct them to an array.
The example uses the "external reference" trick similar to: http://flows.nodered.org/flow/810bc88d27f705510093
Warning: This trick is based on the fact that when the "clone" package clones functions, it does not clone their scope. The behavior may change in the future.
| [{"id":"bea747f1.4158b8","type":"inject","name":"Array of low-letter messages","topic":"","payload":"[\"a\", \"b\", \"c\", \"d\", \"e\", \"f\", \"g\"]","payloadType":"string","repeat":"","crontab":"","once":false,"x":173,"y":83.72224521636963,"z":"a2b633a9.5d49d","wires":[["f42cd6b.f0bd328"]]},{"id":"c2852efd.3d7ad","type":"debug","name":"","active":true,"console":"false","complete":"payload","x":600.888916015625,"y":206.27780151367188,"z":"a2b633a9.5d49d","wires":[]},{"id":"f42cd6b.f0bd328","type":"json","name":"","x":390.8333053588867,"y":83,"z":"a2b633a9.5d49d","wires":[["663e1cfb.99c1e4"]]},{"id":"a541dc43.5abe2","type":"function","name":"manipulate each element","func":"msg.payload = msg.payload.toUpperCase();\nreturn msg;","outputs":1,"x":198.6111068725586,"y":206.333345413208,"z":"a2b633a9.5d49d","wires":[["cc207b5b.33df88"]]},{"id":"cc207b5b.33df88","type":"function","name":"reconstruct array","func":"var mapResult = msg.mapResult();\nmapResult.result[msg.index] = msg.payload;\nmapResult.countdown -= 1;\nif (0 === mapResult.countdown) {\n return {\n payload: mapResult.result\n };\n}\n","outputs":1,"x":424.1666488647461,"y":206.33334350585938,"z":"a2b633a9.5d49d","wires":[["c2852efd.3d7ad"]]},{"id":"663e1cfb.99c1e4","type":"function","name":"split elements","func":"var mapResult = {\n countdown: msg.payload.length,\n result: msg.payload.map(function(){})\n};\nreturn [msg.payload.map(function(element, index) {\n return {\n payload: element,\n index: index,\n mapResult: function() {\n return mapResult;\n }\n };\n})];\n","outputs":1,"x":574,"y":83,"z":"a2b633a9.5d49d","wires":[["a541dc43.5abe2"]]}] |
