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), 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/SAPConcurODBCDriverforUnix.deb

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

rpm -ivh /path/to/driver/SAPConcurODBCDriverforUnix.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-sapconcur/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.

Authenticating to SAP Concur

SAP Concur supports OAuth authentication only. To enable this authentication from all OAuth flows, you must set AuthScheme to OAuth, and you must create a custom OAuth application.

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 SAP Concur'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.

Note: For information about OAuth grant types, and how Desktop client applications call the OAuth2 endpoint to obtain a token, see "Desktop Authentication Grant Types", later in this chapter.

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.

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.
- 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.
- 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.

Desktop Authentication Grant Types

In order to obtain a token, the client application needs to call the Oauth2 endpoint using various grants, depending on the authentication scenarios required. The supported scenarios from our driver are CODE and PASSWORD grant type.

CODE

CODE is the default OAuthGrantType. In addition to the variables already described above, using the CODE grant type requires you to set the following additional variables:

UseSandbox: If you are authenticating via an implementation server, set this to True.
Region: The region of geolocation, received along with the other credentials. Possible values are EU for Europe, CN for China and US (default).

PASSWORD

The PASSWORD grant can be used with a Desktop application, when there is a trust relationship between the user and the application.

In addition to the variables already described above, using the PASSWORD grant type requires you to set the following additional variables:

AuthScheme: OAuthPassword.
Username: The username or userId.
Password: The user's password.
UseSandbox: If you are authenticating using an implementation server, set this to True.

Company-Level Authentication

Company is a top-level principal within the SAP Concur platform. You can obtain an access token and a refresh token on a Company's behalf the same way you can do it for a User.

After creating an custom OAuth application as described in Creating a Custom OAuth Application, you must generate a Company Request Token. If the Company Request Token Tool is available, you can use that. Otherwise, you must contact the SAP Concur support team for generating the Company Request Token.

After the Company Request Token is generated successfully, the request token tool displays the Company UUID and the Company Request Token. Save these values for later use.

In addition to the variables already described above, using company-level authentication, using the CODE grant type requires you to set the following additional variables:

AuthScheme: CompanyLevelAuth.
CompanyId: The Company's unique identifier.
CompanyRequestToken: The generated Company Request Token.
UseSandbox: If you are authenticating using an implementation server, set this to True.

Using the SAP Concur Login ID Variable

Login ID (the user's login ID) can be used if the user account associated with the OAuth 2.0 access token has a Concur account with one of the following roles:

Web Services Administrator for Professional
Can Administer for Standard

Setting Login ID to ALL retrieves information for all accounts that support the Login ID argument.

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 SAP Concur, 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-sapconcur/lib/cdata.odbc.sapconcur.ini':

[Driver]
AnsiCodePage = 932

ODBC Driver for SAP Concur