IO doesn't work with CSV

[kkuchta]

io = sftp.file.open claims to produce an IO-like object. Unfortunately, it doesn't seem to be quite io-like enough for ruby's built-in CSV library. If I do CSV.new(io), I get an error:

ArgumentError: wrong number of arguments (given 2, expected 0..1)
from /Users/kevin/.rvm/gems/ruby-2.3.1/gems/net-sftp-2.1.2/lib/net/sftp/operations/file.rb:85:in `gets'

Tracing this through, it looks like CSV is ultimately trying to call io.get(separator, limit) (which is supported in the full io spec, but sftp's io-like object only allows one argument.

It's pretty simple to reproduce, but here's a test case anyway:

require 'net/sftp'
require 'csv'

Net::SFTP.start(
  '0.0.0.0',
  '...',
  password: '...',
  port: 2222
) do |sftp|
  filepath = './upload/test_file.csv'
  stream = sftp.file.open(filepath)
  csv = CSV.new(stream) # Errors here: wrong number of arguments (given 2, expected 0..1)
end

This isn't an urgent bug for me— I'll just ditch streams entirely and read the whole (small) file into memory before parsing it :). Just thought I'd log this in case someone else runs into the same issue (or in case I'm missing something and it's not a bug).

[kwerle]

Yup. I'll be doing the same workaround for the same issue.

[jstuckey]

I ran into this issue as well.

A workaround using streams is to provide a row separator to CSV::new (assuming you know it in advance). This skips over the problematic code in CSV#init_separators that tries to automatically detect the separator using io.get(separator, limit).

stream = sftp.file.open(filepath)
csv = CSV.new(stream, row_sep: "\n")

[mfazekas]

Thanks for the report! PR-s are welcome!

[jstuckey]

@mfazekas I'll give it a shot!