Archive for the ‘Gotchas’ Category

cURL stripping newlines from your CSV or other file?

Thursday, January 26th, 2012

I’m in the process of writing a REST endpoint for uploading CSVs to Crossbar as part of our communications platform at 2600hz. Not wanting to invoke the full REST client interface, I generally use cURL to send the HTTP requests. Today, however, I had quite the time figuring out why my CSV files were being stripped of their newline characters.

The initial invocation:

$> curl http://localhost:8000/v1/path/to/upload -H "Content-Type: text/csv" -X POST -d @file.csv

Walking through the code, from where I was processing the CSV down to the webserver handling the connection itself, looking for who was stripping the newlines, I determined it was coming in sans-newlines and decided to check out cURL’s man pages for what might be amiss. I quickly found that the -d option was treating the file as ascii, and although the docs don’t explicitly say so, it appears this option will strip the newlines.

The resolution is to use the –data-binary flag so cURL doesn’t touch the file before sending it to the server.