1.5.
EXAMPLE INTERACTIVE SESSION
CHAPTER 1.
INTRODUCTION
returns a set of all task IDs known to the system. The status (including any returned result and
error codes) of these tasks can then be queried by accessing the fields of the Task object in the
usual way. Note that, in order to get a consistent snapshot of a task’s state, it is advisable to call
the “get record” function.
1.5
Example interactive session
This section describes how an interactive session might look, using the python XML-RPC client
library.
First, initialise python and import the library
xmlrpclib
:
\$ python2.4
...
>>> import xmlrpclib
Create a python object referencing the remote server:
>>> xen = xmlrpclib.Server("https://localhost:443")
Acquire a session reference by logging in with a username and password (error-handling ommitted
for brevity; the session reference is returned under the key
’Value’
in the resulting dictionary)
>>> session = xen.session.login_with_password("user", "passwd")[’Value’]
When serialised, this call looks like the following:
<?xml version=’1.0’?>
<methodCall>
<methodName>session.login_with_password</methodName>
<params>
<param>
<value><string>user</string></value>
</param>
<param>
<value><string>passwd</string></value>
</param>
</params>
</methodCall>
Next, the user may acquire a list of all the VMs known to the system: (Note the call takes the
session reference as the only parameter)
>>> all_vms = xen.VM.get_all(session)[’Value’]
>>> all_vms
[’OpaqueRef:1’, ’OpaqueRef:2’, ’OpaqueRef:3’, ’OpaqueRef:4’ ]
The VM references here have the form
OpaqueRef:X
, though they may not be that simple in the
future, and you should treat them as opaque strings.
Templates
are VMs with the
is a template
field set to true. We can find the subset of template VMs using a command like the following:
>>> all_templates = filter(lambda x: xen.VM.get_is_a_template(session, x)[’Value’], all_vms)
Once a reference to a VM has been acquired a lifecycle operation may be invoked:
>>> xen.VM.start(session, all_templates[0], False, False)
{’Status’: ’Failure’, ’ErrorDescription’: [’VM_IS_TEMPLATE’, ’OpaqueRef:X’]}
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