Linux DSN Configuration
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/GoogleSheetsODBCDriverforUnix.deb
On systems that support the RPM package format, run the following command with root or sudo:
rpm -ivh /path/to/driver/GoogleSheetsODBCDriverforUnix.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-googlesheets/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 Google Sheets
The driver supports authentication schemes using user accounts, service accounts, GCP instance accounts, and API keys for authentication. Each of these types of accounts have different AuthSchemes, but all of them use the OAuth standard for authentication.| Access | AuthScheme | Notes |
| User Accounts | OAuth | Can use embedded credentials if access from a Desktop application. See Desktop Applications, below. |
| Service Accounts | OAuthJWT | Depends on whether the data will be JSON or PFX files. See Authenticating as a Service, below. |
| GCP Instance Acct | GCPInstanceAccount | For use on a GCP virtual machine. |
| API Key | Token | Also, set APIKey to True. To create an API key in the Google Cloud Console, click Create credentials > API Key. To restrict the key before using it in production, select Restrict and choose one of the available restrictions. |
The following sections focus on authentication as a User, and authentication as a Service.
Authenticating as a User (OAuth)
The following subsections describe how to authenticate to Google Sheets from a User account (AuthScheme OAuth) via three common authentication flows:
- Desktop: a connection to a server on the user's local machine, frequently used for testing and prototyping. Authenticated via either embedded OAuth or custom OAuth.
- Web: access to data via a shared website. Authenticated via custom OAuth only.
- Headless Server: a dedicated computer that provides services to other computers and their users, which is configured to operate without a monitor and keyboard. Authenticated via embedded OAuth or custom OAuth.
For information about how to create a custom OAuth application, and why you might want to create one even for auth flows that have embedded OAuth credentials, see Creating a Custom OAuth Application. For a complete list of connection string properties available in Google Sheets, see Connection.
Desktop Applications
CData provides an embedded OAuth application that simplifies authentication at the desktop. You can also authenticate from the desktop via a custom OAuth application, which you configure and register at the Google Sheets console. For further information, see Creating a Custom OAuth Application.Before you connect, set the following variables:
- InitiateOAuth: GETANDREFRESH. Used to automatically get and refresh the OAuthAccessToken.
- Custom OAuth applications only:
- OAuthClientId: The client Id assigned when you registered your custom OAuth application.
- OAuthClientSecret: The client secret assigned when you registered your custom OAuth application.
- CallbackURL: The redirect URI defined when you registered your custom OAuth application.
When you connect, the driver opens Google Sheets'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:
- The first time you connect to data, 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.
- On subsequent data connections, set the following:
- InitiateOAuth
- OAuthSettingsLocation
Manual refresh of the OAuth access token:
The only value needed to manually refresh the OAUth access token is the OAuth refresh token.
- To manually refresh the OAuthAccessToken after the ExpiresIn period (returned by GetOAuthAccessToken) has elapsed, call the RefreshOAuthAccessToken stored procedure.
- Set the following connection properties:
- OAuthClientId: The Client Id in your application settings.
- OAuthClientSecret: The Client Secret in your application settings.
- Call RefreshOAuthAccessToken with OAuthRefreshToken set to the OAuth refresh token returned by GetOAuthAccessToken.
- After the new tokens have been retrieved, set the OAuthAccessToken property to the value returned by RefreshOAuthAccessToken. This opens a new connection.
Store the OAuth refresh token so that you can use it to manually refresh the OAuth access token after it has expired.
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:
-
Authenticate from the machine with an internet browser, and obtain the OAuthVerifier connection property.
If you are using the embedded OAuth application, call the GetOAuthAuthorizationURL stored procedure. Open the URL returned by the stored procedure in a browser.
If you are using a custom OAuth application, 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.
-
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.
-
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.
-
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.
- Custom OAuth applications only:
- OAuthClientId: The client Id in your custom OAuth application settings.
- OAuthClientSecret: The client secret in the custom OAuth application settings.
-
Test the connection to generate the OAuth settings file.
-
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.
- Custom OAuth applications only:
- 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.
- Custom OAuth applications only:
- OAuthClientId: The client Id assigned when you registered your custom OAuth application.
- OAuthClientSecret: The client secret assigned when you registered your custom OAuth application.
Authenticating as a Service (OAuthJWT)
Authenticating to Google Sheets from a Service account (AuthScheme OAuth) requires:- The creation of a new service account (see Creating a Custom OAuth Application); and
- A copy of the accounts certificate.
You must also set the following properties, which are specific to the preferred medium:
JSON File Properties
- AuthScheme: OAuthJWT.
- OAuthJWTCertType: GOOGLEJSON.
- OAuthJWTCert: The path to the Google-provided .json file.
- OAuthJWTSubject (optional): The email address of the user whose data you want to access. Only set this value if the service account is part of a GSuite domain and you want to enable delegation.
PFX File Properties
- AuthScheme: OAuthJWT.
- OAuthJWTCertType: PFXFILE.
- OAuthJWTCert: The path to the Google-provided .pfx file.
- OAuthJWTIssuer: The email address of the service account. This address usually includes the domain iam.gserviceaccount.com.
- OAuthJWTCertPassword (optional): The .pfx file password. In most cases you must provide this since Google encrypts PFX certificates.
- OAuthJWTCertSubject (optional): Set this only if you are using a OAuthJWTCertType which stores multiple certificates. Should not be set for PFX certificates generated by Google.
- OAuthJWTSubject (optional): The email address of the user whose data you want to access. Only set this value if the service account is part of a GSuite domain and you want to enable delegation.
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 Google Sheets, 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-googlesheets/lib/cdata.odbc.googlesheets.ini':
[Driver]
AnsiCodePage = 932