limited to first 10 lines, just for example
[{"id":"117a41275d1be480","type":"csv","z":"8be23377afc3327e","name":"","sep":",","hdrin":true,"hdrout":"none","multi":"one","ret":"\\n","temp":"","skip":"0","strings":true,"include_empty_strings":false,"include_null_values":false,"x":550,"y":200,"wires":[["23b1ee0e0ad9681e"]]},{"id":"f5d13f178f205ce6","type":"http request","z":"8be23377afc3327e","name":"Test","method":"GET","ret":"txt","paytoqs":"ignore","url":"https://data.nationalgrideso.com/backend/dataset/22bc9bdd-4919-439a-95b8-5213bb3bdf4c/resource/a2dd7992-32d5-4723-b0f5-273caaecbde1/download/service-update-industry-notifications-test150220231030.csv","tls":"","persist":false,"proxy":"","insecureHTTPParser":false,"authType":"","senderr":false,"headers":[],"x":430,"y":200,"wires":[["117a41275d1be480"]]},{"id":"23b1ee0e0ad9681e","type":"switch","z":"8be23377afc3327e","name":"","property":"parts.index","propertyType":"msg","rules":[{"t":"lt","v":"10","vt":"num"}],"checkall":"true","repair":false,"outputs":1,"x":690,"y":200,"wires":[["d16dc28241588aaf"]]},{"id":"6e75254b2a6dbc45","type":"inject","z":"8be23377afc3327e","name":"Test","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":310,"y":200,"wires":[["f5d13f178f205ce6"]]},{"id":"d16dc28241588aaf","type":"debug","z":"8be23377afc3327e","name":"debug 192","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":910,"y":240,"wires":[]}]
but if the online service has ssh you should be able to do some thing like scp user@host:/some/file /dev/stdout | head > destfile using the exec node Depending on your set up.
