Connect to FTP Data in Ruby

The CData ODBC Driver for FTP makes it easy to integrate connectivity to live FTP data in Ruby. This article shows how to create a simple Ruby app that connects to FTP data, executes a query, and displays the results.

Create an ODBC Connection to FTP Data

If you have not already, first specify connection properties in an ODBC DSN (data source name). This is the last step of the driver installation. You can use the Microsoft ODBC Data Source Administrator to create and configure ODBC DSNs.

To connect to FTP or SFTP servers, specify at least RemoteHost and FileProtocol. Specify the port with RemotePort.

Set User and Password to perform Basic authentication. Set SSHAuthMode to use SSH authentication. See the Getting Started section of the data provider help documentation for more information on authenticating via SSH.

Set SSLMode and SSLServerCert to secure connections with SSL.

The data provider lists the tables based on the available folders in your FTP server. Set the following connection properties to control the relational view of the file system:

• RemotePath: Set this to the current working directory.
• TableDepth: Set this to control the depth of folders to list as views.
• FileRetrievalDepth: Set this to retrieve and list files recursively from the root table.

Stored Procedures are available to download files, upload files, and send protocol commands. See the Data Model chapter of the FTP data provider documentation for more information.

Installing Ruby and Necessary Gems

If you do not have Ruby installed, refer to the Ruby installation page. With Ruby installed, you will need to install the ruby-dbi, dbd-odbc, and ruby-odbc gems:

gem install dbi
gem install dbd-odbc
gem install ruby-odbc

Create a Ruby App with Connectivity to FTP Data

Create a new Ruby file (for example: FTPSelect.rb) and open it in a text editor. Copy the following code into your file:

#connect to the DSN
require 'dbi'
cnxn = DBI.connect('DBI:ODBC:CData FTP Source','','')

#execute a SELECT query and store the result set
resultSet = cnxn.execute("SELECT Filesize, Filename FROM MyDirectory")

#display the names of the columns
resultSet.column_names.each do |name|
 print name, "\t"
end
puts

#display the results
while row = resultSet.fetch do
 (0..resultSet.column_names.size - 1).each do |n|
 print row[n], "\t"
 end
 puts
end
resultSet.finish

#close the connection
cnxn.disconnect if cnxn

With the file completed, you are ready to display your FTP data with Ruby. To do so, simply run your file from the command line:

ruby FTPSelect.rb

Writing SQL-92 queries to FTP allows you to quickly and easily incorporate FTP data into your own Ruby applications. Download a free trial today!