#!/usr/bin/expect --
# Script: sftp_file_from.tcl
# Description: Utility to SFTP a file from(i.e. get) a host(i.e. source)
# usage: sftp_file_to.tcl source_host user pass source_directory local_directory file_name_to_ftp


# Set named parameters
set source_host              [lindex $argv 0]
set sftp_user                [lindex $argv 1]
set sftp_pass                [lindex $argv 2]
set source_directory         [lindex $argv 3]
set local_directory          [lindex $argv 4]
set file_name                [lindex $argv 5]
set sftp_prompt "sftp>?"
set timeout 300

#exp_internal 1;

# Procedure to connect to SFTP server
proc connect { sftp_pass } {
  variable sftp_prompt
  variable source_host
  expect -re "Are you sure you want to continue.*" { exp_send "YES\r"; exp_continue } \
         -re "(Password|password).*:.*"            { exp_send "$sftp_pass\r"; exp_continue } \
         -re $sftp_prompt                          { return 0 } \
         eof                                       { puts "***Error connecting to($source_host)."; return 1 }
         timeout                                   { puts "***Error connecting to($source_host)."; return 1 }
  }

# Procedure to send meesage denoting error, then quit SFTP, then exit with status denoting error.
proc abort { msg } {
  puts "$msg";
  exp_send "quit\r";
  exit 1;
  }

# Connect to the SFTP server
spawn sftp $sftp_user@$source_host
set connect_results [connect $sftp_pass]

# If successful connection, continue, else exit denoting error occured.
if { $connect_results == 0 } {
  # Change to source directory on source server.
  exp_send "cd $source_directory\r"
    expect "No such file or directory" { abort "\n**Error changing to directory($source_directory) on source server." } \
           -re $sftp_prompt            {} \
           timeout { abort "\n**Error changing to directory($source_directory) on source server." }

  # Change local directory.
  exp_send "lcd $local_directory\r"
    expect "No such file or directory" { abort "\n**Error changing to directory($local_directory) on local host." } \
           -re $sftp_prompt            {} \
           timeout { abort "\n**Error changing to directory($local_directory) on local host." }

  # Get file from source host
  set timeout 1800
  exp_send "get $file_name\r"
    expect "not found."                { abort "\n***Error transfering file($file_name) FROM: $source_host)." } \
           -re $sftp_prompt            {} \
           timeout { abort "\n***Error transfering file($file_name) FROM: $source_host)." }

  # QUIT!!
  exp_send "quit\r"
  # Successful SFTP session so exit with zero status
  exit 0
}
# Error connecting to SFTP server so exit with non-zero status
exit 1