Make a Connection to the
CIMOM
Before you can enumerate classes, invoke
methods, or examine properties of the managed server, you must create a
connection object in your client. The connection object manages the connection
with the CIM server, accepts CIM methods by proxy, and passes them to the CIM
server. The following pseudocode illustrates how to create a connection by
using command-line parameters passed to the client.
To make a connection to the CIMOM
- Collect the connection parameters from the environment.use os function parse_environment() ///Check if all parameters are set in the shell environment./// VI_SERVER = VI_USERNAME = VI_PASSWORD = VI_NAMESPACE=Null ///Any missing environment variable is cause to revert to command-line arguments./// try return { 'VI_SERVER':os.environ['VI_SERVER'], \ 'VI_USERNAME':os.environ['VI_USERNAME'], \ 'VI_PASSWORD':os.environ['VI_PASSWORD'], \ 'VI_NAMESPACE':os.environ['VI_NAMESPACE'] } catch return Null use sys function get_params() ///Check if parameters are passed on the command line./// param_host = param_user = param_password = param_namespace = Null if len( sys.argv ) == 5 print 'Connect using command-line parameters.' param_host, param_user, param_password, param_namespace = sys.argv [ 1:5 ] return { 'host':param_host, \ 'user':param_user, \ 'password':param_password, \ 'namespace':param_namespace } env = parse_environment() if env print 'Connect using environment variables.' return { 'host':env['VI_SERVER'], \ 'user':env['VI_USERNAME'], \ 'password':env['VI_PASSWORD'], \ 'namespace':env['VI_NAMESPACE'] } else print 'Usage: ' + sys.argv[0] + ' <host> <user> <password> [<namespace>]' print ' or set environment variables: VI_SERVER, VI_USERNAME, VI_NAMESPACE' return Null params = get_params() if params is Null exit(-1)
- Create the connection object in the client.use wbemlib connection = Null function connect_to_host( params ) ///Connect to the server./// connection = wbemlib.WBEMConnection( 'https://' + params['host'], \ ( params['user'], params['password'] ), \ params['namespace'] ) return connection if connect_to_host( params ) print 'Connected to: ' + params['host'] + ' as user: ' + params['user'] else print 'Failed to connect to: ' + params['host'] + ' as user: ' + params['user']With some client libraries, creating a connection object in the client does not send a request to the CIMOM. A request is not sent until a method is called. To verify that such a client can connect to and authenticate with the server, see another use case, such as Listing Registered Profiles in the CIM Implementation.