File over tcp? with out using net/ftp


#1

Im trying to send a file back and forth between a client.rb and
server.rb…

How can i do this with out using ftp?


#2

Bigmac T. wrote:

Im trying to send a file back and forth between a client.rb and
server.rb…

How can i do this with out using ftp?

There are gazillion other protocols for transferring files expect FTP.

For example, you can use HTTP. Write a tiny server with Sinatra, and the
client with Mechanize.

You can also write your own protocol.


#3

Albert S. wrote:

Bigmac T. wrote:

Im trying to send a file back and forth between a client.rb and
server.rb…

How can i do this with out using ftp?

There are gazillion other protocols for transferring files expect FTP.

For example, you can use HTTP. Write a tiny server with Sinatra, and the
client with Mechanize.

You can also write your own protocol.

Sorry, I didn’t notice the “back and forth” part. So HTTP isn’t very
suitable for this. Right now I can’t think of some other protocol.

What’s the problem with FTP?


#4

On 08.05.2009 01:51, Bigmac T. wrote:

Im trying to send a file back and forth between a client.rb and
server.rb…

How can i do this with out using ftp?

You can use DRb or simply stream it through a socket.

Kind regards

robert


#5

Bigmac T. wrote:

I have been doing a lot of google’n trying to find example code for
sending files threw the socket… I would really like to see some
exmaple code for the client and server… im clueless…

Hi Bigmac, here is a simple exemple you can begin with.

  • Client (sends the file) :
    require ‘socket’
    file = File.new(‘file.jpg’)
    fileContent = file.read
    sock = TCPSocket.open(‘localhost’, 2000)
    sock.print fileContent
    sock.close

  • Server (receives the file) :
    require ‘socket’
    sock = TCPServer.open(2000)
    con = sock.accept
    msg = con.read
    destFile = File.new(‘file-received.jpg’, ‘w’)
    destFile.print msg
    destFile.close

Have fun
ChoBolT


#6

Robert K. wrote:

On 08.05.2009 01:51, Bigmac T. wrote:

Im trying to send a file back and forth between a client.rb and
server.rb…

How can i do this with out using ftp?

You can use DRb or simply stream it through a socket.

Kind regards

robert

I have been doing a lot of google’n trying to find example code for
sending files threw the socket… I would really like to see some
exmaple code for the client and server… im clueless…

server.rb

require ‘socket’
data = file.socket(“c:\file.txt”) #???
server = TCPServer.new(1234)
loop do
Thread.start(server.accept) do |connection|
print connection
connection.write(data)
end
end


#7

On 09.05.2009 10:03, Philippe Chotard wrote:

Bigmac T. wrote:

I have been doing a lot of google’n trying to find example code for
sending files threw the socket… I would really like to see some
exmaple code for the client and server… im clueless…

Hi Bigmac, here is a simple exemple you can begin with.

A few remarks:

  • Client (sends the file) :
    require ‘socket’
    file = File.new(‘file.jpg’)
    fileContent = file.read

The file handle is not closed properly. These two lines above can be
replaced by

fileContent = File.read(‘file.jpg’)

sock = TCPSocket.open(‘localhost’, 2000)
sock.print fileContent

I’d rather use sock.write here as this is the more low level output
operation.

sock.close

  • Server (receives the file) :
    require ‘socket’
    sock = TCPServer.open(2000)
    con = sock.accept
    msg = con.read
    destFile = File.new(‘file-received.jpg’, ‘w’)
    destFile.print msg
    destFile.close

Again, I’d rather use #write instead of #print here. And use the block
form of File.open.

Some more general remarks: depending on operating systems involved files
should probably opened rather in binary mode than text mode.

Then, as files can grow quite large, your approach (i.e. reading the
whole file into memory before writing it) is likely to fail for large
files. Usually a solution with small chunks is better.

Kind regards

robert


#8

Robert K. wrote:

On 09.05.2009 10:03, Philippe Chotard wrote:

Bigmac T. wrote:

I have been doing a lot of google’n trying to find example code for
sending files threw the socket… I would really like to see some
exmaple code for the client and server… im clueless…

Hi Bigmac, here is a simple exemple you can begin with.

A few remarks:

  • Client (sends the file) :
    require ‘socket’
    file = File.new(‘file.jpg’)
    fileContent = file.read

The file handle is not closed properly. These two lines above can be
replaced by

fileContent = File.read(‘file.jpg’)

sock = TCPSocket.open(‘localhost’, 2000)
sock.print fileContent

I’d rather use sock.write here as this is the more low level output
operation.

sock.close

  • Server (receives the file) :
    require ‘socket’
    sock = TCPServer.open(2000)
    con = sock.accept
    msg = con.read
    destFile = File.new(‘file-received.jpg’, ‘w’)
    destFile.print msg
    destFile.close

Again, I’d rather use #write instead of #print here. And use the block
form of File.open.

Some more general remarks: depending on operating systems involved files
should probably opened rather in binary mode than text mode.

Then, as files can grow quite large, your approach (i.e. reading the
whole file into memory before writing it) is likely to fail for large
files. Usually a solution with small chunks is better.

Kind regards

robert

This is vary helpful… will be easy for me to build functions off this
example…

i have tested with this and it works with text files but thats it…
image files and executable’s dont function after being sent threw the
socket…you said i should open files in binary mode? how can i do this
and then after words will the files function properly?

i have been trying to get the client to receive files from the server…
could i see one more example if its not to much to ask?


#9

2009/5/11 Albert S. removed_email_address@domain.invalid:

Do:

file = File.new(‘file.jpg’, ‘b’)
destFile = File.new(‘file-received.jpg’, ‘wb’)

I would do that regardless of platform for these reasons

  • documentation (immediately clear that this file is treated as binary),
  • portability of programs.

Kind regards

robert


#10

Bigmac T. wrote:

i have tested with this and it works with text files but thats it…
image files and executable’s dont function after being sent threw the
socket…you said i should open files in binary mode? how can i do this
and then after words will the files function properly?

You’re probbaly using Windows. Instead of:

file = File.new(‘file.jpg’)
destFile = File.new(‘file-received.jpg’, ‘w’)

Do:

file = File.new(‘file.jpg’, ‘b’)
destFile = File.new(‘file-received.jpg’, ‘wb’)


#11

file = File.new(‘file.jpg’, ‘b’)
destFile = File.new(‘file-received.jpg’, ‘wb’)

I figured this out the other day… im still having trouble getting the
client to download a file from the server… the process is in my head
but i cant implement this…

This is my attempt… i have been playing around with this code but i
cant figure it out…

#server.rb
require ‘socket’

 fileContent = File.read('text.txt')

sock = TCPServer.open(2000)
con = sock.accept
sock.print fileContent
sock.close

#client.rb
require ‘socket’

  sock = TCPSocket.open('localhost', 2000)
destFile = File.new('c:\\hacked\\text.txt', 'w')
destFile.print
destFile.close

#12

Bigmac T. wrote:

#client.rb
require ‘socket’

  sock = TCPSocket.open('localhost', 2000)
destFile = File.new('c:\\hacked\\text.txt', 'w')
destFile.print

That prints nothing to destFile. You probably need something like:

data = sock.read
destFile.print data

Your server also needs to loop accepting connections, and ideally
threads to service multiple clients concurrently. Have a look at
gserver.rb in the standard library.