This section describes how to set up ODBC connectivity and configure DSNs on several Linux distributions: Debian-based systems, like Ubuntu, and Red Hat Linux platforms, like Red Hat Enterprise Linux (RHEL) and Fedora.

Minimum Linux Versions

Here are the minimum supported versions for Red Hat-based and Debian-based systems:

OS	Min. Version
Ubuntu	18.04
Debian	10
RHEL	8
Fedora	28
SUSE	15

Installing the Driver Dependencies

Run the following commands as root or with sudo to install the necessary dependencies:

• Debian/Ubuntu:
  

  apt-get install libc6 libstdc++6 zlib1g libgcc1

• RHEL/Fedora:
  

  yum install glibc libstdc++ zlib libgcc

Installing the Driver

You can use standard package management systems to install the driver.

On Debian-based systems, like Ubuntu, run the following command with root or sudo:

dpkg -i /path/to/driver/setup/ZendeskODBCDriverforUnix.deb 

On systems that support the RPM package format, run the following command with root or sudo:

rpm -ivh /path/to/driver/ZendeskODBCDriverforUnix.rpm 

Licensing the Driver

Run the following commands to license the driver. To activate a trial, omit the <key> input.

cd /opt/cdata/cdata-odbc-driver-for-zendesk/bin/
sudo ./install-license.sh <key>

Connecting through the Driver Manager

The driver manager loads the driver and passes function calls from the application to the driver. You need to register the driver with the driver manager and you define DSNs in the driver manager's configuration files.

The driver installation registers the driver with the unixODBC driver manager and creates a system DSN. The unixODBC driver manager can be used from Python and from many other applications. Your application may embed another driver manager.

Creating the DSN

See Using unixODBC to install unixODBC and configure DSNs. See Using the DataDirect Driver Manager to create a DSN to connect to OBIEE, Informatica, and SAS.

Connecting to Zendesk

To connect to Zendesk, set the URL (Zendesk Support URL), using the format https://{subdomain}.zendesk.com. Once connected, user authenticate as described in the following section.

In addition, users who work with archived data for the TicketMetrics table must set the UseIncrementalAPI property to True.

Authenticating to Zendesk

Zendesk supports two types of authentication, depending on whether the user is connecting directly to their own local data (basic authentication) or connecting to shared data via a browser (OAuth authentication).

Basic Authentication

To use Basic authentication, specify an email address and either a Password or an ApiToken. Set User to your email address, and then use the Zendesk Support admin interface to do the following:

1. Enable password access.
2. Set AuthScheme to Basic while using APIToken Authentication.
3. At Admin > Channels > API, manage API tokens. Only one token can be active at a time. Deleting a token deactivates it permanently.

OAuth Authentication

Zendesk supports OAuth authentication for all instances where the user is accessing shared data via the network. This means that, regardless of whether authentication originates at the Web, a Desktop, or a Headless Server, you must set AuthScheme to OAuth, and you must create a custom OAuth application.

The following subsections describe how to authenticate to Zendesk from three common authentication flows:

• Desktop: a connection to a server on the user's local machine, frequently used for testing and prototyping.
• Web: access to data via a shared website.
• Headless Server: a dedicated computer that provides services to other computers and their users, which is configured to operate without a monitor and keyboard.

For information about how to create a custom OAuth application, see Creating a Custom OAuth Application. For a complete list of connection string properties available in Zendesk, see Connection.

Desktop Applications

To authenticate with the credentials for a custom OAuth application, you must get and refresh the OAuth access token. After you do that, you are ready to connect.

Get and refresh the OAuth access token:

• InitiateOAuth = GETANDREFRESH. Used to automatically get and refresh the OAuthAccessToken.
• OAuthClientId = the client Id assigned when you registered your application.
• OAuthClientSecret = the client secret that was assigned when you registered your application.
• CallbackURL = the redirect URI that was defined when you registered your application.

When you connect, the driver opens Zendesk's OAuth endpoint in your default browser. Log in and grant permissions to the application.

When the access token expires, the driver refreshes it automatically.

Automatic refresh of the OAuth access token:

To have the driver automatically refresh the OAuth access token, do the following:

1. Before connecting to data for the first time, set the following connection parameters:
   • InitiateOAuth = REFRESH.
   • OAuthClientId = the client Id in your application settings.
   • OAuthClientSecret = the client secret in your application settings.
   • OAuthAccessToken = the access token returned by GetOAuthAccessToken.
   • OAuthSettingsLocation = the path where you want the driver to save the OAuth values, which persist across connections.
2. On subsequent data connections, set the following:
   • InitiateOAuth
   • OAuthSettingsLocation

Headless Machines

If you need to log in to a resource that resides on a headless machine, you must authenticate on another device that has an internet browser. You can do this in either of the following ways:

• Option 1: Obtain the OAuthVerifier value.
• Option 2: Install the driver on a machine with an internet browser and transfer the OAuth authentication values after you authenticate through the usual browser-based flow.

After you execute either Option 1 or Option 2, configure the driver to automatically refresh the access token on the headless machine.

Option 1: Obtaining and Exchanging a Verifier Code

To obtain a verifier code, you must authenticate at the OAuth authorization URL. Do the following:

1. Authenticate from the machine with an internet browser, and obtain the OAuthVerifier connection property.

   Set the following properties:

   • InitiateOAuth = OFF.
   • OAuthClientId = the client Id assigned when you registered your application.
   • OAuthClientSecret = the client secret assigned when you registered your application.

2. Call the GetOAuthAuthorizationURL stored procedure. The stored procedure returns the CallbackURL established when the custom OAuth application was registered. (See Creating a Custom OAuth Application.)

   Copy this URL and paste it into a new browser tab.

3. Log in and grant permissions to the driver. The OAuth application redirects you the redirect URI, with a parameter called code appended. Note the value of this parameter; you will need it later, to configure the OAuthVerifier connection property.

4. Exchange the OAuth verifier code for OAuth refresh and access tokens. On the headless machine, set the following connection properties to obtain the OAuth authentication values:

   • InitiateOAuth = REFRESH.
   • OAuthVerifier = the noted verifier code (the value of the code parameter in the redirect URI).
   • OAuthSettingsLocation = persist the encrypted OAuth authentication values to the specified file.
   • OAuthClientId = the client Id in your custom OAuth application settings.
   • OAuthClientSecret = the client secret in the custom OAuth application settings.

5. Test the connection to generate the OAuth settings file.

6. After you re-set the following properties, you are ready to connect:

   • InitiateOAuth = REFRESH.
   • OAuthSettingsLocation = the file containing the encrypted OAuth authentication values. To enable the automatic refreshing of the access token, be sure that this file gives read and write permissions to the driver.
   • OAuthClientId = the client Id assigned when you registered your application.
   • OAuthClientSecret = the client secret assigned when you registered your application.

Option 2: Transferring OAuth Settings

Prior to connecting on a headless machine, you must install and create a connection with the driver on a device that supports an internet browser. Set the connection properties as described above in "Desktop Applications".

After completing the instructions in "Desktop Applications", the resulting authentication values are encrypted and written to the path specified by OAuthSettingsLocation. The default filename is OAuthSettings.txt.

Test the connection to generate the OAuth settings file, then copy the OAuth settings file to your headless machine.

To connect to data via the headless machine, set the following connection properties:

• InitiateOAuth = REFRESH
• OAuthSettingsLocation = the path to the OAuth settings file you copied from the machine with the browser. To enable automatic refreshing of the access token, ensure that this file gives read and write permissions to the driver.
• OAuthClientId = the client Id assigned when you registered your custom OAuth application.
• OAuthClientSecret = the client secret assigned when you registered your custom OAuth application.

Refreshing OAuth Values

The driver can refresh the temporary OAuth access tokens obtained during the browser-based OAuth authentication exchange. By default, the driver saves the encrypted tokens in the odbc.ini file corresponding to the DSN. Access to this odbc.ini file can be restricted in the case of System DSNs.

To enable the automatic token exchange, you can give the driver write access to the system odbc.ini. Or, you can set the OAuthSettingsLocation connection property to an alternate file path, to which the driver would have read and write access.

    OAuthSettingsLocation=/tmp/oauthsettings.txt
    

Installing Dependencies for OAuth Authentication

The OAuth authentication standard requires the authenticating user to interact with Zendesk, using a web-browser. If the first OAuth interaction is to be done on the same machine the driver is installed on, for example, a desktop application, the driver needs access to the xdg-open program, which opens the default browser.

To satisfy this dependency, install the corresponding package with your package manager:

Debian/Ubuntu Package	RHEL/Fedora Package	File
xdg-utils	xdg-utils	xdg-open

Set the Driver Encoding

The ODBC drivers need to specify which encoding to use with the ODBC Driver Manager. By default, the CData ODBC Drivers for Unix are configured to use UTF-16 which is compatible with unixODBC, but other Driver Managers may require alternative encoding.

Alternatively, if you are using the ODBC driver from an application that uses the ANSI ODBC API it may be necessary to set the ANSI code page. For example, to import Japanese characters in an ANSI application, you can specify the code page in the config file '/opt/cdata/cdata-odbc-driver-for-zendesk/lib/cdata.odbc.zendesk.ini':

[Driver]
AnsiCodePage = 932