Connect to Linear Data in Ruby

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

Create an ODBC Connection to Linear 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.

You can authenticate to Linear with a personal API key or with OAuth 2.0. The API key is the simplest option for connecting with your own Linear account.

Authenticating with an API Key

Set the following connection properties:

• AuthScheme: Set this to APIKey.
• APIKey: A Linear personal API key.

To create a personal API key, log in to Linear, open Settings > Security & access > Personal API keys, select New API key, and create it. Copy the key immediately, because Linear shows it only once.

Authenticating with OAuth

OAuth requires a custom OAuth application registered in Linear (Settings > API > OAuth applications), which provides the OAuthClientId and OAuthClientSecret. Two flows are supported:

• Authorization code: Set AuthScheme to OAuth, InitiateOAuth to GETANDREFRESH, and provide OAuthClientId, OAuthClientSecret, and the CallbackURL defined in your application (e.g., http://localhost:33333). The driver opens Linear in your browser so you can grant access.
• Client credentials: Set AuthScheme to OAuthClient and provide OAuthClientId and OAuthClientSecret. This authenticates the application itself, with no browser interaction, and suits machine-to-machine integrations.

By default, the driver requests the read,write scopes. The driver refreshes the access token automatically when it expires.

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 Linear Data

Create a new Ruby file (for example: LinearSelect.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 Linear Source','','')

#execute a SELECT query and store the result set
resultSet = cnxn.execute("SELECT id, name FROM Team WHERE key = 'ENG'")

#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 Linear data with Ruby. To do so, simply run your file from the command line:

ruby LinearSelect.rb

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