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), CentOS, and Fedora.

Minimum Linux Versions

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

OS	Min. Version
Ubuntu	11.04
Debian	7
RHEL	6.9
CentOS	6.9
Fedora	13
SUSE	12.1

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/CentOS/Fedora:
  

  yum install glibc libstdc++ zlib libgcc

Here are the corresponding libraries required by the driver:

Debian/Ubuntu Package	RHEL/CentOS/Fedora Package	File
libc6	glibc	linux-vdso.1
libc6	glibc	libm.so.6
libc6	glibc	librt.so.1
libc6	glibc	libdl.so.2
libc6	glibc	libpthread.so.0
libc6	glibc	libc.so.6
libc6	glibc	ld-linux-x86-64.so.2
libstdc++6	libstdc++	libstdc++.so.6
zlib1g	zlib	libz.so.1
libgcc1	libgcc	libgcc_s.so.1

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/FacebookODBCDriverforUnix.deb 

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

rpm -ivh /path/to/driver/FacebookODBCDriverforUnix.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-facebook/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 Facebook

Before you can connect to Facebook, you must obtain the appropriate connection properties. Since Facebook supports user authentication only via OAuth, you must either use the CData-supplied embedded OAuth application or create a custom OAuth application, as described in Creating a Custom OAuth Application.

You can also set the following optional connection properties:

• Target: This property enables you to filter the results of all queries in the connection to records that match a specified target. For example, to retrieve comments on a video, specify the Id of the video as the target. To specify this restriction per query, use the table's Target column.
• AggregateFormat: This property enables you to return aggregate columns as XML data rather than JSON (the default format).

Authenticating to Facebook

The following subsections describe how to authenticate to Facebook from any available OAuth access flow. For information about creating a custom OAuth application, see Creating a Custom OAuth Application.

Desktop Applications

CData provides an embedded OAuth application that simplifies OAuth desktop Authentication. You can also create a custom OAuth application, as described in Creating a Custom OAuth Application.

For authentication, the only difference between the two methods is that to connect via a custom OAuth application you must set the following connection properties:

• OAuthClientId: (custom applications only) Set to the client Id in your application settings.
• OAuthClientSecret: (custom applications only) Set to the client secret in your application settings.
• CallbackURL: Set to the Redirect URL in your application settings.
• Scope (optional): Set this only if you need to customizie the permissions that the driver requests.
• AuthenticateAsPage (optional): Set this to a page name or Id to make requests as a page. The page must be managed by the authenticated user.

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

Web Applications

When connecting via a Web application, you must create and register a custom OAuth application with Facebook, as described in Creating a Custom OAuth Application. You can then use the driver to get and manage the OAuth token values.

Get an OAuth Access Token

To obtain the OAuthAccessToken set the following connection properties:

• OAuthClientId: Set to the client Id in your application settings.
• OAuthClientSecret: Set to the client secret in your application settings
• Scope (optional): Set only if you need to customizie the permissions that the driver requests.
• AuthenticateAsPage (optional): Set to a page name or Id to make requests as a page. The page must be managed by the authenticated user.

Now call stored procedures to complete the OAuth exchange:

1. Call the GetOAuthAuthorizationURL stored procedure. Set the AuthMode input to WEB and set the CallbackURL input to the Redirect URI you specified in your app settings. If necessary, set the "Scope" parameter to request custom permissions.
2. Open the URL, log in, and authorize the application. You are redirected back to the callback URL.
3. Call the GetOAuthAccessToken stored procedure. Set the AuthMode input to WEB. Set the Verifier input to the "code" parameter in the query string of the callback URL. If necessary, set the "Scope" parameter to request custom permissions.

To connect to data, set the OAuthAccessToken connection property to the access token returned by the stored procedure. When the access token expires after ExpiresIn seconds, call GetOAuthAccessToken again to obtain a new access token.

Headless Machines

To configure the driver to use OAuth with a user account on a headless machine, you must authenticate on another device that has an internet browser.

Creating a custom OAuth app is optional in the headless OAuth flow; if you want to skip creating an app, you can connect with the driver's embedded OAuth credentials. However, you might want to create a custom OAuth app to change the information displayed when users log into Facebook to grant permissions to the driver. For information on how to create a custom OAuth application, see Creating a Custom OAuth Application.

1. Choose one of these two options:
   • Option 1: Obtain the OAuthVerifier value as described in "Obtain and Exchange a Verifier Code", below.
   • Option 2: Install the driver on another machine and transfer the OAuth authentication values after you authenticate through the usual browser-based flow, as described in "Transfer OAuth Settings", below.
2. Configure the driver to automatically refresh the access token from the headless machine.

Option 1: Obtain and Exchange a Verifier Code

To obtain a verifier code, you must authenticate at the OAuth authorization URL. Follow the steps below to authenticate from the machine with an internet browser and obtain the OAuthVerifier connection property.

1. If you are using the Embedded OAuth Application:
   1. Call the GetOAuthAuthorizationURL stored procedure.
   2. Click Facebook OAuth endpoint to open the endpoint in your browser.
2. If you are using a custom OAuth application, create the Authorization URL by setting the following properties:
   • InitiateOAuth: Set to OFF.
   • OAuthClientId: Set to the client Id assigned when you registered your application.
   • OAuthClientSecret: Set to the client secret assigned when you registered your application.
3. Call the GetOAuthAuthorizationURL stored procedure with the CallbackURI input parameter set to the exact Redirect URI you specified in your application settings.
4. Open the URL returned by the stored procedure in a browser.
5. Log in and grant permissions to the driver. You are then redirected to the callback URL, which contains the verifier code.
6. Save the value of the verifier code. Later you will set this in the OAuthVerifier connection property.

Finally, on the headless machine, set the following connection properties to obtain the OAuth authentication values:

• OAuthClientId: Set to the Client ID in your OAuth Integration settings.
• OAuthClientSecret: Set to the Client Secret in your OAuth Integration settings.
• OAuthVerifier: Set to the verifier code.
• OAuthSettingsLocation: Set to persist the encrypted OAuth authentication values to the specified location.
• InitiateOAuth: Set to REFRESH.

Connect to Data

After the OAuth settings file is generated, set the following properties to connect to data:

• OAuthSettingsLocation: Set to the location containing the encrypted OAuth authentication values. Make sure this location gives read and write permissions to the provider to enable the automatic refreshing of the access token.
• InitiateOAuth: Set to REFRESH.

Option 2: Transfer OAuth Settings

To install the driver on another machine, authenticate, and then transfer the resulting OAuth values:

1. On a second machine, install the driver and connect with the following properties set:
   • OAuthSettingsLocation: Set to a writable location.
   • OAuthClientId: Set to the client ID in your app settings.
   • OAuthClientSecret: Set to the client secret in your app settings.
   • CallbackURL: Set to the callback URL in your app settings.
2. Test the connection to authenticate. The resulting authentication values are written and encrypted to the path specified by OAuthSettingsLocation. After you have successfully tested the connection, copy the OAuth settings file to your headless machine. On the headless machine, set the following connection properties to connect to data:
   • InitiateOAuth: Set to REFRESH.
   • OAuthSettingsLocation: Set to the location of your OAuth settings file. Make sure this location gives read and write permissions to the driver to enable the automatic refreshing of the access token.

Requesting Additional Permissions

You may find while using the driver that Facebook returns an error stating your app does not have permissions to do a certain action. To resolve this, you must generate a new OAuth access token with the required permissions. Set the Scope property in the authentication step for a desktop application. You can find a list of available Facebook permissions here:

http://developers.facebook.com/docs/authentication/permissions/

Permissions that may be required depending on your use case are:

user_birthday, user_photos, user_videos, user_likes, user_hometown, user_location, read_insights, pages_manage_metadata, pages_read_engagement, pages_read_user_content, pages_messaging, business_management, instagram_basic, instagram_manage_insights

Note that in some cases, permissions restrictions might not be due to missing but requestable Facebook OAuth permissions, but instead might be due to missing OAuth app features, like Page Public Content Access or Page Public Metadata Access. These features are tied to the OAuth app as a whole, and cannot be approved or denied for individual OAuth access tokens requested by users. Consider Creating a Custom OAuth Application if you need access to app features not available with the embedded OAuth app.

AuthenticateAsPage Property

Use the AuthenticateAsPage connection property if you want to post as a single page. To query collections of pages, leave AuthenticateAsPage blank, in which case CData tools automatically detect which page tokens to use.

The following sections compare the two options.

Posting as a Page

After authenticating to Facebook with your user account, you can post, etc. as one of the pages you manage: Set the AuthenticateAsPage property to the Id of the page you want. You can find the Ids for all pages your account has access to by querying the Pages view.

Automatic Page

Facebook has made a number of recent changes that require page tokens for most resources owned by a page. This can be troublesome if you manage multiple pages and want to execute the same queries across all pages (such as retrieving Insights). In order to make this work seamlessly with our tools, we have added a way to automatically detect the page token to use. For this to work, simply do not specify the AuthenticateAsPage. Note that the correct page token can only be resolved if the page id is specified as part of the target in the request. This means for some requests you will still need to manually specify AuthenticateAsPage.

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 Facebook, 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/CentOS/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-facebook/lib/cdata.odbc.facebook.ini':

[Driver]
AnsiCodePage = 932