I’m trying to use the Net::FTP class to send a text file to my FTP
server, but I don’t have an actual text file to send. Instead I want
to send it a multi-line string as my “file”. (I’m using Builder to
generate an XML file and I don’t want to have to physically save it to
a file before sending it.)
The Net::FTP class has a method called puttextfile that seems to be
defined like this:
but I don’t have a local filename to provide. Is there anything I can
use that would substitute for one?
I tried to use a StringIO object, hoping to use that as my
“localfile”:
s = StringIO.new(xml_data)
but when I try to send it like this:
Net::FTP.open(“domain.com”, “username”, “secret”) do |ftp|
ftp.puttextfile(s, ‘\data\file.xml"’)
end
I get this error:
TypeError: can’t convert StringIO into String
from c:/ruby/lib/ruby/1.8/net/ftp.rb:571:in open' from c:/ruby/lib/ruby/1.8/net/ftp.rb:571:in puttextfile’
from (irb):33
from c:/ruby/lib/ruby/1.8/net/ftp.rb:115:in `open’
from (irb):32
Obviously it wants a filename, and I’m giving it the actual IO object
instead. .NET had the concept of IO streams, and I was hoping to use
something like that here, but I can’t figure out how.
but I don’t have a local filename to provide. Is there anything I can
use that would substitute for one?
I ended up subclassing and providing the functionality myself.
In case it helps anyone, here’s what I came up with: two methods,
get_text_lines and send_text_lines. See below for complete source
(it’s not too long). Suggestions for making the code more elegant are
definitely welcome.
Jeff
require ‘net/ftp’
class JeffFTP < Net::FTP
Sends a collection of lines to be saved in a file on the server
lines can be an array, or anything responding to #each
def send_text_lines(lines, remotefile, &block) # :yield: line
storlines_from_array("STOR " + remotefile, lines, &block)
end
Gets a file from the server as a collection of text lines.
If you don’t provide a block, it will return an array of lines.
If you provide a block, each line will be passed to the block,
and the return value will be an empty array.
Large files should use the block form.
def get_text_lines(remotefile, &block) # :yield: line
lines = []
retrlines("RETR " + remotefile) do |line|
if block
yield(line)
else
lines << line
end
end
lines
end
private
def storlines_from_array(cmd, lines, &block) # :yield: line
synchronize do
voidcmd(“TYPE A”)
conn = transfercmd(cmd)
lines.each do |line|
conn.write(line)
yield(line) if block
end
conn.close
voidresp
end
end
from c:/ruby/lib/ruby/1.8/net/ftp.rb:115:in `open'
from (irb):32
Obviously it wants a filename, and I’m giving it the actual IO object
instead. .NET had the concept of IO streams, and I was hoping to use
something like that here, but I can’t figure out how.
Any ideas?
Try turning the problem around and look at using open-uri instead of
Net::FTP? This extends Kernel::open so that it accepts ftp and http
urls as well as file names. This makes the ftp server look like a
local file.