Red Hat NETWORK 3.5 - PROVISIONING, Reference Manual

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Appendix B.
RHN API Access
In an effort to provide customers with added flexibility, RHN makes an application programming
interface (API) available. This interface can be found by clicking
Help
at the top-right corner of
the RHN website, then clicking API in the left navigation bar. Or you may go directly to:
https://rhn.redhat.com/rpc/api/. You should use this URL for your XMLRPC server, as well as your
browser.
Warning
This API should be considered experimental and used strictly for evaluation by advanced users. Red
Hat strongly discourages you from using this interface to alter production systems, unless you are
sure your changes will not result in errors.
The RHN API is based upon XML-RPC, which allows distinct pieces of software on disparate systems
to make remote procedure calls using XML over HTTP. For this reason, any calls you make are
expected to meet the constraints of XML-RPC. You can find out more at http://www.xmlrpc.com/.
Because the RHN API is self-documenting and subject to change, this section bypasses a list of classes
and methods (which can be found within the interface) in favor of tips for using the API efficiently.
These include steps for determining required values and a sample script that makes some of the calls.
B.1. Using the auth Class and Getting the Session
It is worth noting you will almost invariably use the auth class first. This class offers a single method,
login. Use this to establish an RHN session. It requires values for three parameters: username, pass-
word, and duration. The first two come directly from your RHN account, while the third is the length
of time the session should last in seconds, typically 1200. It will return a session string than can be
used in all other methods.
B.2. Obtaining the system_id
Many of the methods require a value for the system_id parameter. This is the unique
alphanumeric value assigned to each system when registered to RHN. It can be found within
the
/etc/sysconfig/rhn/systemid
file on the machine. In addition, you may use the
download_system_id method within the system class to obtain the value.
B.3. Determining the sid
Several methods require a value for the sid, or server ID, parameter. Note that this is different from
the system_id. You may determine the sid of a machine in two different ways. First, you can log into
the RHN website, click the name of a system, and view the sid at the end of the URL in the location
bar. It will be after the equal (=) sign in something like, "index.pxt?sid=1003486534". Second, you
may use the list_user_systems method within the system class to obtain a list of systems available to
the user that contains the associated sids.