InfluxDB: input validation function for influxdb-out
This is a simple function node designed to validate data that you want to store in InfluxDB via the influxdb-out node from node-red-contrib-influxdb.
The structure of data for InfluxDB can be rather confusing. While influxdb-out makes it simpler, the instructions could be clearer. Because putting the wrong type of data or using the wrong structure when outputting can be hard to fix due to the way that InfluxDB works, it is much easier to validate things before they get there.
The flow comes with a bunch of test inputs to help you understand the data and potential issues (and they let me test the function).
Let me know if there are any errors or you would like something else added to the function.
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It must be an object containing fieldName:fieldValue pairs or a single value (which would be written to the `value` field name).')\n return\n} else {\n // Otherwise, we always use 'value' as the default field name\n fields = {'value': msg.payload}\n}\n\nconst lstFields = Object.keys(fields)\n\n// check to make sure that there is a value field name - if not, continue but with a warning\nif ( ! lstFields.includes('value') ) {\n // Lets us turn off the warning if we know what we are doing :-)\n if ( msg.noValueField !== true )\n node.warn('Default field name \"vaue\" not present, was that deliberate? 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If present, it **MUST** be an object containing tagName:tagValue pairs.\n\nWe will ALWAYS use the \"array containing two objects\" payload\nOR the singe Object payload (if no tags being used).\n\n## Tests\n* _SUCCESS_: \n `msg={\"payload\":{\"fieldName1\":10,\"value\":15},\"tags\":{\"tagName1\":\"tagname1Value\"},\"measure\":\"myMeasure1\"}`\n* _SUCCESS_ (payload converted to `{\"value\":16}`): \n `msg={\"payload\":16,\"tags\":{\"tagName1\":\"tagname1Value\"},\"measure\":\"myMeasure2\"}`\n* _SUCCESS_ (no tags): \n `msg={\"payload\":16,\"measure\":\"myMeasure2\"}`\n* _SUCCESS_ (but warning issued, no value field): \n `msg={\"payload\":{\"fieldName2\":17},\"tags\":{\"tagName1\":\"tagname1Value\"},\"measure\":\"myMeasure3\"}`\n* _SUCCESS_ (value \"On\" converted to 1): \n `msg={\"payload\":\"On\",\"measure\":\"myMeasure4\"}`\n* _???_ (missing tags for a measure with tags): \n `msg={\"payload\":\"On\",\"measure\":\"myMeasure1\"}`\n* _FAIL_: No `msg.measure`\n* _FAIL_: `msg.payload` is an 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