Node-RED通过HTTP向InfluxDB写入数据报错问题求助

Let's break down why you're hitting this error and how to fix it quickly:

The Root Cause #

Your working curl command sends the InfluxDB line protocol as raw plain text, but your Node-RED HTTP Request node is wrapping that line protocol in a JSON object (as seen in the error message: {"url":"...","method":"POST","body":"..."}). InfluxDB tries to parse this entire JSON string as line protocol, which obviously doesn't match the expected format—hence the "missing tag value" error.

Step-by-Step Fix #

1. Configure the HTTP Request Node Correctly

   • Double-click the HTTP Request node to open its settings:
     • Set Method to POST
     • Enter your full InfluxDB write URL: http://192.168.1.116:8086/write?db=waterlevel
     • Go to the Body tab:
       • Select String as the body type (not JSON)
       • Paste your line protocol directly into the input field: vattenstand,lake=siljan,region=dalarna value=160.80
     • Go to the Headers tab:
       • Click Add header
       • Set the header key to Content-Type and the value to text/plain (this tells InfluxDB exactly what format the body is in)
   • Save the node configuration and deploy your flow.

2. Verify the Fix
   When you trigger the flow, the Node-RED node will now send the exact same raw plain text payload that your curl command uses—InfluxDB will parse it correctly and write the data without errors.

Why This Works #

Your curl command uses --data-binary to send the line protocol as raw text. By setting the Node-RED node to send a plain string body with the text/plain content type, you're replicating that exact behavior, which aligns with InfluxDB's /write endpoint requirements.

内容的提问来源于stack exchange，提问作者m4rt1n