2.2. Using the pywbemcli command line general options

2.2.1. Overview of the general options

General options define:

General options must be entered on the command line before the command group or command.

For example the following enumerates qualifier declarations and outputs the result in the simple table format:

pywbemcli --output-format simple --server http://localhost qualifier enumerate
Qualifier Declarations
Name         Type     Value    Array    Scopes       Flavors
-----------  -------  -------  -------  -----------  ---------------
Description  string            False    ANY          EnableOverride
                                                     ToSubclass
                                                     Translatable
Key          boolean  False    False    PROPERTY     DisableOverride
                                        REFERENCE    ToSubclass

In interactive mode, general options from the command line are defined once and retain their value throughout the execution of the interactive mode.

General options defined in the command line may be overwritten by specifying them on interactive mode commands. The resulting new value is used only for that one command, and is not retained between interactive mode command executions.

In the following example, the --output-format general option is used on an interactive mode command to overwrite the default output format, and the --server general option is used to overwrite the server that was specified in the command line invocation:

$ pywbemcli --server http://myserver

pywbemcli> --output-format table --server http://localhost qualifier enumerate
Qualifier Declarations
+-------------+---------+---------+---------+-----------+-----------------+
| Name        | Type    | Value   | Array   | Scopes    | Flavors         |
+=============+=========+=========+=========+===========+=================+
| Description | string  |         | False   | ANY       | EnableOverride  |
|             |         |         |         |           | ToSubclass      |
|             |         |         |         |           | Translatable    |
+-------------+---------+---------+---------+-----------+-----------------+
| Key         | boolean | False   | False   | PROPERTY  | DisableOverride |
|             |         |         |         | REFERENCE | ToSubclass      |
+-------------+---------+---------+---------+-----------+-----------------+

2.2.1.1. Defining the WBEM server

The target WBEM server can be defined on the command line in several ways with the following arguments :

  1. Define connection information for a WBEM server by using the --server general option that specifies the URL of the server.

    The following general options can be used for specifying additional information for the connection:

  2. Define a mock WBEM server by using the --mock-server general option.

    The mock WBEM server is part of pywbemcli and allows testing or demonstrating pywbemcli without having access to a real WBEM server. For details, see Mock WBEM server support.

  3. Refer to a persisted connection definition for either a WBEM server or mock WBEM server by using the --name general option that specifies the name of the connection definition.

    Persisted connection definitions are stored in a connections file and are managed with the connection command group.

2.2.1.2. Controlling operation behavior and monitoring operations

Several general options control the behavior and monitoring of the operations executed against the WBEM server.

The DMTF specifications allow alternative forms of some operations, pywbemcli implements this flexibility and controls the choice of either the pull operations or the traditional operations through the --use-pull general option. With this option the user can choose to use either type of operation if that operation is available on the WBEM server. See Pywbemcli and the DMTF pull operations for more information on pull operations.

Since the pull operations include the ability to select the maximum size of returned chunks of data, the --pull-max-cnt general option can be used to control response chunk sizes.

In many cases it is important to the user to be able to monitor details of the operations executed against the WBEM server, either the APIs executed in pywbem, or the HTTP requests and responses and the time statistics for these operations.

The --log general option provides the capability to log information about this flow including:

  • The API calls and responses/exceptions executed by pywbem.
  • the HTTP requests and responses that pass between pywbemcli and the WBEM server.

The --log general option configures the logging including what is logged and the destination for the log output.

Thus, for example, the following command enumerates qualifiers and writes the log entries for the CIM-XML HTTP requests and responses to the pywbemcli log file pywbemcli.log:

$ pywbemcli --output-format table --server http://localhost --log http=file qualifier enumerate
<displays table of qualifier declarations>

$ cat pywbemcli.log
2019-09-16 21:14:04,296-pywbem.http.1-21020-Connection:1-21020 WBEMConnection(url='http://localhost', ...)
2019-09-16 21:14:04,297-pywbem.http.1-21020-Request:1-21020 POST /cimom 11 http://localhost
    CIMOperation:'MethodCall' CIMMethod:'EnumerateQualifiers' CIMObject:u'root/cimv2'
    <?xml version="1.0" encoding="utf-8" ?>
    <CIM CIMVERSION="2.0" DTDVERSION="2.0"><MESSAGE ID="1001" PROTOCOLVERSION="1.0">
    ...
    </CIM>
. . .

2.2.1.3. Controlling output formats

Pywbemcli supports multiple output formats for command results by using the --output-format general option.

The output formats fall into several groups (table formats, CIM object formats, text formats, and a tree format); however, not all formats are supported or applicable for all commands. For more details, see Output formats.

2.2.1.4. Other miscellaneous general options

The --verbose general option displays extra information about the pywbemcli internal processing.

The --warn general option controls the display of warnings.

The --version general option displays pywbemcli version information and the --help general option provides top level help

2.2.1.5. General options descriptions

This section defines in detail the requirements, characteristics, and any special syntax of each general option.

2.2.1.6. --server general option

The argument value of the --server/-s general option is a string that is the URL of the WBEM server to which pywbemcli will connect, in the format:

[SCHEME://]HOST[:PORT]

Where:

  • SCHEME: The protocol to be used. Must be “https” or “http”. Default: “https”.
  • HOST: The WBEM server host. Must be a short hostname, fully qualified DNS hostname, literal IPv4 address, or literal IPv6 address. See RFC3986 and RFC6874 for details.
  • PORT: The WBEM server port to be used. Default: 5988 for HTTP, and 5989 for HTTPS.

This option is mutually exclusive with the --name general option and the --mock-server general option since each defines a connection to a WBEM server.

In the interactive mode the connection is not actually established until a command requiring access to the WBEM server is entered.

Examples for the argument value of this option include:

https://localhost:15345       # https, port 15345, hostname localhost
http://10.2.3.9               # http, port 5988, IPv4 address 10.2.3.9
https://10.2.3.9              # https, port 5989, IPv4 address 10.2.3.9
http://[2001:db8::1234-eth0]  # http, port 5988, IPv6 address 2001:db8::1234, interface eth0

2.2.1.7. --name general option

The argument value of the --name/-n general option is a string that is the name of a connection definition in the connections file. The parameters for this named connection definition will be loaded from the connections file to become the current WBEM connection in pywbemcli.

In the interactive mode the connection is not actually established until a command requiring access to the WBEM server is entered.

This option is mutually exclusive with the --server general option and the --mock-server general option since each defines a connection to a WBEM server.

The following example creates a connection definition named myserver in the connections file, and then uses that connection to execute class get:

$ pywbemcli --server http://localhost --user me --password mypw connection save myserver

$ pywbemcli --name myserver class get CIM_ManagedElement
<displays MOF for CIM_ManagedElement>

See connection command group for more information on managing connections.

2.2.1.8. --default-namespace general option

The argument value of the --default-namespace/-d general option is a string that defines the default CIM namespace to use for the target WBEM server.

If this option is not specified, the default namespace will be root/cimv2.

The default namespace will be used if the --namespace/-n command option is not used on a command.

Some commands execute against multiple or all namespaces, for example the the class find command.

2.2.1.9. --user general option

The argument value of the --user/-u general option is a string that is the user name for authenticating with the WBEM server.

2.2.1.10. --password general option

The argument value of the --password/-p general option is a string that is the password for authenticating with the WBEM server.

This option is normally required if the --user general option is defined. If passwords are saved into the connections file, they are not encrypted in the file.

If the WBEM operations performed by any pywbemcli command require a password, the password is prompted for if --user/-u is used (in both modes of operation) and --password/-p is not used.

$ pywbemcli --server http://localhost --user me class get
Enter password: <password>
. . . <The display output from get class>

If both --user/-u and --password/-p are used, the command is executed without a password prompt:

$ pywbemcli --server http://localhost --user me --password blah class get
. . . <The display output from get class>

If the operations performed by a particular pywbemcli command do not require a password or no user is supplied, no password is prompted. For example:

$ pywbemcli --help
. . . <help output>

For script integration, it is important to have a way to avoid the interactive password prompt. This can be done by storing the password string in an environment variable or specifying it on the command line. See Environment variables for general options.

The pywbemcli connection export command outputs the (bash/Windows) shell commands to set all needed environment variables.

The environment variable output is OS dependent. Thus for example in Unix type OSs:

$ pywbemcli --server http://localhost --user fred connection export
export PYWBEMCLI_SERVER=http://localhost
export PYWBEMCLI_NAMESPACE=root/cimv2
...

This ability can be used to set those environment variables and thus to persist the connection name in the shell environment, from where it will be used in any subsequent pywbemcli commands:

$ eval $(pywbemcli --server http://localhost --user fred connection export)

$ env | grep PYWBEMCLI
export PYWBEMCLI_SERVER=http://localhost
export PYWBEMCLI_NAMESPACE=root/cimv2

$ pywbemcli server namespaces
. . . <list of namespaces for the defined server>

2.2.1.11. --timeout general option

The argument value of the --timeout/-t general option is an integer that defines the client side timeout in seconds. The pywbem client includes a timeout mechanism that closes a WBEM connection if there is no response to a request to the WBEM server in the time defined by this value. Pywbemcli defaults to a predefined timeout (normally 30 seconds) if this option is not defined.

2.2.1.12. --verify general option

The pair of --verify and --no-verify general options control whether or not the client verifies any certificates received from the WBEM server.

By default or if --verify is specified, any certificates returned by the server are verified. If --no-verify is specified, any certificates returned by the server are accepted without verification.

This general option uses the approach with two long option names to allow the user to specifically enable or disable certificate verification when this general option is used in interactive mode.

2.2.1.13. --certfile general option

The argument value of the --certfile general option is the file path of a PEM file containing a X.509 client certificate to be presented to the WBEM server during the TLS/SSL handshake, enabling 2-way (mutual) authentication. This option is used only with HTTPS.

If --certfile is not used, no client certificate is presented to the server, resulting in 1-way authentication during the TLS/SSL handshake.

For more information on authentication types, see: https://pywbem.readthedocs.io/en/stable/client/security.html#authentication-types

2.2.1.14. --keyfile general option

The argument value of the --keyfile general option is the file path of a PEM file containing the private key belonging to the public key that is part of the X.509 certificate. See --certfile general option for more information.

Not required if the private key is part of the file defined in the --certfile option. --keyfile is not allowed if --certfile is not provided. Default: No client key file. The client private key should then be part of the file defined by --certfile.

2.2.1.15. --ca-certs general option

The argument value of the --ca-certs general option specifies which X.509 certificates are used on the client side for validating the X.509 certificate received from the WBEM server during SSL/TLS handshake when HTTPS is used.

The client-side and server-side certificates may be CA certificates (i.e. certificates issued by a certificate authority) or self-signed certificates.

Its value must be one of:

  • The path name of a file in PEM format that contains one or more certificates. See the description of the ‘CAfile’ argument of the OpenSSL SSL_CTX_load_verify_locations() function for details.
  • The path name of a directory with files in PEM format, each of which contains exactly one certificate. The file names must follow a particular naming convention. See the description of the ‘CApath’ argument of the OpenSSL SSL_CTX_load_verify_locations() function for details.
  • The string ‘certifi’ (only for pywbem version 1.0 or later). This choice will cause the certificates provided by the certifi package to be used. That package provides the certificates from the Mozilla Included CA Certificate List. Note that this list only contains CA certificates, so this choice does not work if the WBEM server uses self-signed certificates.

The default behavior depends on the version of the installed pywbem package:

  • Starting with pywbem version 1.0, the default is the behavior described above for the string ‘certifi’.
  • Before pywbem version 1.0, the default is the path name of the first existing directory from a list of system directories where certificates are expected to be stored.

The version of the installed pywbem package can be displayed using the --version general option.

Specifying the --no-verify option (see --verify general option) bypasses client side verification of the WBEM server certificate.

2.2.1.16. --timestats general option

The --timestats / --no-timestats -T general option is a boolean option that enables the display of time statistics on the interactions with the WBEM server.

When the option is included on the command line, the display of statistics is enabled after each command in the interactive mode and before exit in the command mode.

Statistics are always gathered in pywbemcli for the current connection for every command executed. They can be displayed at any time in the interactive mode with the command statistics show.

For more information on statistics gathered by pywbemcli and WBEM servers see section statistics command group .

2.2.1.17. --use-pull general option

The argument value of the --use-pull/-u general option determines whether the pull operations or traditional operations are used for the instance enumerate, instance references, instance associators and instance query commands. See Pywbemcli and the DMTF pull operations for more information on pull operations. The choices for the argument value are as follows:

  • yes - pull operations will be used and if the server does not support pull, the request will fail.
  • no - forces pywbemcli to try only the traditional non-pull operations.
  • either - (default) pywbem tries both; first pull operations and then traditional operations.

2.2.1.18. --pull-max-cnt general option

The argument value of the --pull-max-cnt general option is an integer passed to the WBEM server with the open and pull operation requests. This integer tells the server the maximum number of objects to be returned for each pull request if pull operations are used. This must be a positive non-zero integer. The default is 1000. See Pywbemcli and the DMTF pull operations for more information on pull operations.

2.2.1.19. --mock-server general option

The argument value of the --mock-server/-m general option is a file path of a MOF file or Python script that loads a mock WBEM server in the pywbemcli process with mock data (i.e. CIM objects). This allows pywbemcli to be used without access to a real WBEM server.

This option may be specified multiple times.

This option may be specified multiple times to define multiple MOF and Python files that make up the definition of a mock server. The files must have the suffix “.mof” for MOF files and “.py” for Python scripts.

When this option is used, the security options (ex. --user) are irrelevant; they may be specified but are not used.

The following example creates a mock server with two files defining the mock data, shows what parameters are defined for the connection, and then saves that connection named mymockserver:

$ pywbemcli --mock-server classdefs.mof --mock-server insts.py --default-namespace root/myhome

pywbemcli> connection show
name: not-saved (current)
  server:
  mock-server: classdefs.mof, insts.py
  . . .

pywbemcli> connection save mymockserver

See chapter Mock WBEM server support for more information on defining the files for a mock server.

2.2.1.20. --output-format general option

The argument value of the --output-format/-o general option is a string that defines the output format in which the result of any pywbemcli commands is displayed. The default output format depends on the command.

For details, see Output formats.

2.2.1.21. --log general option

The argument value of the --log/-l general option defines the destination and parameters of logging of the requests and responses to the WBEM server.

For details, see Pywbemcli defined logging.

2.2.1.22. --verbose general option

The --verbose/-v general option is a boolean option that enables the display of extra information about the processing.

In particular it outputs text for a number of commands that normally return nothing upon successful execution(ex. instance delete, instance enumerate that returns no CIM objects) to indicate the successful command completion.

2.2.1.23. --connections-file general option

The --connections-file/-C general option allows the user to select a path name for the connections file.

By default, the path name of the connections file is the value of the PYWBEMCLI_CONNECTIONS_FILE environment variable or if not set, the file .pywbemcli_connections.yaml in the user’s home directory. The user’s home directory depends on the operating system used and is determined with os.path.expanduser("~"), which works on all operating systems including Windows. See expanduser() for details.

The actually used path name of the connections file is shown in the connection list command.

The connection definitions in the connections file are managed with the commands in the connection command group.

In the interactive mode, this option may not be modified after the command line is processed.

2.2.1.24. --warn general option

The --warn/--no-warn general option is a boolean option that controls the display of all Python warnings.

If --warn is used, all Python warnings are shown once. If --no-warn is used (default), the PYTHONWARNINGS environment variable determines which warnings are shown. If that variable is not set, no warnings are shown. See PYTHONWARNINGS for details.

2.2.1.25. --pdb general option

The --pdb general option is a boolean option that enables debugging with the built-in pdb debugger.

If debugging is enabled, execution of the pywbemcli command will pause just before the command within pywbemcli is executed, and the pdb debugger prompt will appear. See pdb debugger commands for details on how to operate the built-in pdb debugger.

2.2.1.26. --version general option

The --version general option displays the version of the pywbemcli command and the version of the pywbem package used by it, and then exits.

2.2.1.27. --help general option

The --help/-h general option displays help text which describes the command groups and general options, and then exits.

2.2.2. Environment variables for general options

Pywbemcli defines environment variables corresponding to its general options as follows:

Environment variable Corresponding general option
PYWBEMCLI_SERVER --server
PYWBEMCLI_NAME --name
PYWBEMCLI_USER --user
PYWBEMCLI_PASSWORD --password
PYWBEMCLI_OUTPUT_FORMAT --output-format
PYWBEMCLI_DEFAULT_NAMESPACE --default-namespace
PYWBEMCLI_TIMEOUT --timeout
PYWBEMCLI_KEYFILE --keyfile
PYWBEMCLI_CERTFILE --certfile
PYWBEMCLI_CA_CERTS --ca-certs
PYWBEMCLI_USE_PULL --use-pull
PYWBEMCLI_PULL_MAX_CNT --pull-max-cnt
PYWBEMCLI_STATS_ENABLED --timestats
PYWBEMCLI_MOCK_SERVER (1) --mock-server
PYWBEMCLI_LOG --log
PYWBEMCLI_PDB --pdb
PYWBEMCLI_CONNECTIONS_FILE --connections-file

Notes:

  1. The --mock-server general option can be specified multiple times. To do that with the PYWBEMCLI_MOCK_SERVER environment variable, separate the multiple path names with space.

If these environment variables are set, the corresponding general options default to the value of the environment variables. If both an environment variable and its corresponding general option are set, the command line option overrides the environment variable with no warning.

Environment variables are not provided for command options or command arguments.

In the following example, the pywbemcli command uses server http://localhost defined by the environment variable:

$ export PYWBEMCLI_SERVER=http://localhost
$ pywbemcli class get CIM_ManagedElement
  <displays MOF for CIM_ManagedElement>

The pywbemcli connection export command outputs the (bash/Windows) shell commands to set all of the environment variables:

$ pywbemcli --server http://localhost --user fred connection export
export PYWBEMCLI_SERVER=http://localhost
export PYWBEMCLI_NAMESPACE=root/cimv2
. . .

This can be used to set those environment variables and thus to persist the connection name in the shell environment, from where it will be used in any subsequent pywbemcli commands:

$ eval $(pywbemcli --server http://localhost --user fred)

$ env | grep PYWBEMCLI
export PYWBEMCLI_SERVER=http://localhost
export PYWBEMCLI_NAMESPACE=root/cimv2
. . .

$ pywbemcli server namespaces
. . . <list of namespaces for the defined server>

2.2.3. Pywbemcli and the DMTF pull operations

The DMTF specifications and pywbem includes two ways to execute the enumerate instance type operations (Associators, References, EnumerateInstances, ExecQuery):

Pywbem implements an overlay of the above two operations called the Iter.. operations where each Iter.. operation executes either the traditional or pull operation depending on a parameter of the connection.

While the pull operations may not be supported by all WBEM servers they can be significantly more efficient for large responses when they are available. Pywbem implements the client side of these operation and pywbemcli provides for the use of these operations through two general options:

  • --use-pull - This option allows the user to select from the the following alternatives:
    • either - (default) pywbemcli first tries the open operation and if that is not implemented by the server retries the operation with the corresponding traditional operation. The result of this first operation determines whether pull or the traditional operation are used for any further requests during the current pywbem interactive session.
    • yes - Forces the use of the pull operations and fails if that is not implemented by the server.
    • no - Forces the use of the traditional operation.
  • --pull-max-cnt - Sets the maximum count of objects the server is allowed to return for each open/pull operation. The default is 1000 objects which from experience is a logical choice.

The default alternative either is probably the most logical setting for --use-pull, unless you are specifically testing the use of pull operations.

However, there are some limitations with using the either choice as follows:

  • The original operations did not support the filtering of responses with a query language query (--filter-query-language and --filter-query ) which requests that the WBEM server filter the responses before they are returned. This can greatly reduce the size of the responses if effectively used but is used only when the pull operations are available on the server.
  • The pull operations do not support some of the options that traditional operations do:
  • --include-qualifiers - Since even the traditional operations specification deprecated this option and the user cannot depend on it being honored, the most logical solution is to never use this option.
  • --local-only - Since even the traditional operations specification deprecated this option and the user cannot depend on it being honored by the WBEM server, the most logical solution is to never use this option.

The following example forces the use of the pull operations and expects the WBEM server to return no more than 10 instances per request. It fails if the pull operations are not supported in the WBEM server:

$ pywbemcli --server http://localhost --use-pull=yes --pull-max-cnt=10 instance enumerate CIM_Foo

2.2.4. Output formats

Pywbemcli supports multiple output formats to present command results. The output format can be selected with the --output-format general option. The allowed output formats are different for the various command groups and commands.

The output formats fall into several groups:

  • Table formats - The Table formats format the result as a table with rows and columns. Many of the result types allow table formatted response display including:
    • instance get, instance enumerate, instance references, instance associators where the table formats are alternatives to the CIM model formats that shows the properties for each instance as a column in a table.
    • instance count
    • server commands
    • class find
    • connection commands
  • CIM object formats - The CIM object formats format a result that consists of CIM objects in MOF, CIM-XML or pywbem repr format. All of the commands that return CIM objects support these output formats.
  • ASCII tree format - The ASCII tree format formats the result as a tree, using ASCII characters to represent the tree to show the hierarchial relationship between CIM classes. The only command supporting the ASCII tree format is class tree, and it supports only that one output format. The tree format is not supported by any other command today.
  • TEXT format - The Text formats is used for commands that output small quantites of text (ex. the interop namespace name) and that could be used as part of a command line redirection.

When an unsupported output format is specified for a command response, it is rejected with an exception. For example, the command class enumerate only supports the CIM object formats and will generate an exception if the command pywbemcli -o table class enumerate is entered.

2.2.4.1. Output formats for groups and commands

Each of the commands may allow only a subset of the possible ouput formats. Thus, the server brand only outputs data in a table format so there is no defined default format for the --output-format general option.

The following shows the default format for each command and the alternate formats where the values mean:

objects: xml, repr, or txt

table: table, plain, simple, grid, psql, rst, text, or html

Group Command Default Alternates Comments
class associators ‘mof’ objects See Note 1 below
class delete None None Nothing returned
class enumerate ‘mof’ objects See Note 1 below
class find ‘simple’ table  
class get ‘mof’ objects See Note 1 below
class invokemethod ‘mof’ objects See Note 1 below
class references ‘mof’ objects See Note 1 below
class tree None None Only outputs as ascii tree
instance associators ‘mof’ objects, table Output as cim object or table of properties
instance count ‘simple’ table  
instance create None None Nothing returned
instance delete None None Nothing returned
instance enumerate ‘mof’ objects, table  
instance get ‘mof’ objects, table  
instance invokemethod ‘mof’ objects, table  
instance modify None None Nothing returned
instance references ‘mof’ table  
qualifier enumerate ‘mof’ table  
qualifier get ‘mof’ table  
server brand ‘text’ text Alternate is table format
server centralinsts ‘simple’ table  
server info ‘simple’ table  
server interop ‘text’ text Alternate is table format
server namespaces ‘simple’ table Alternate is text format
server profiles ‘simple’ table  
connection delete None table  
connection export None table  
connection list ‘simple’ table  
connection save None table  
connection select None None  
connection show None None Currently ignores output format
connection test None None  

NOTES:

  1. The display of classes with the --names-only/--no or --summary/-s command options allows table output formats in addition to the objects output formats.

2.2.4.2. Table formats

The different variations of the table format define different formatting of the borders for tables. The following are examples of the table formats with a single command class find CIM_Foo:

  • --output-format table: Tables with a single-line border. This is the default:

    Find class CIM_Foo*
    +-------------+-----------------+
    | Namespace   | Classname       |
    |-------------+-----------------|
    | root/cimv2  | CIM_Foo         |
    | root/cimv2  | CIM_Foo_sub     |
    | root/cimv2  | CIM_Foo_sub2    |
    | root/cimv2  | CIM_Foo_sub_sub |
    +-------------+-----------------+
    
  • --output-format simple: Tables with a line between header row and data rows, but otherwise without borders:

    Find class CIM_Foo*
    Namespace    Classname
    -----------  ---------------
    root/cimv2   CIM_Foo
    root/cimv2   CIM_Foo_sub
    root/cimv2   CIM_Foo_sub2
    root/cimv2   CIM_Foo_sub_sub
    
  • --output-format plain: Tables do not use any pseudo-graphics to draw borders:

    Find class CIM_Foo*
    Namespace    Classname
    root/cimv2   CIM_Foo
    root/cimv2   CIM_Foo_sub
    root/cimv2   CIM_Foo_sub2
    root/cimv2   CIM_Foo_sub_sub
    
  • --output-format grid: Tables tables formatted by Emacs’ table.el package. It corresponds to grid_tables in Pandoc Markdown extensions:

    Find class CIM_Foo*
    +-------------+-----------------+
    | Namespace   | Classname       |
    +=============+=================+
    | root/cimv2  | CIM_Foo         |
    +-------------+-----------------+
    | root/cimv2  | CIM_Foo_sub     |
    +-------------+-----------------+
    | root/cimv2  | CIM_Foo_sub2    |
    +-------------+-----------------+
    | root/cimv2  | CIM_Foo_sub_sub |
    +-------------+-----------------+
    
  • --output-format rst: Tables in reStructuredText markup:

    Find class CIM_Foo*
    ===========  ===============
    Namespace    Classname
    ===========  ===============
    root/cimv2   CIM_Foo
    root/cimv2   CIM_Foo_sub
    root/cimv2   CIM_Foo_sub2
    root/cimv2   CIM_Foo_sub_sub
    ===========  ===============
    
  • --output-format psql: Like tables formatted by Postgres’ psql cli:

    Find class CIM_Foo*
    ===========  ===============
    Namespace    Classname
    ===========  ===============
    root/cimv2   CIM_Foo
    root/cimv2   CIM_Foo_sub
    root/cimv2   CIM_Foo_sub2
    root/cimv2   CIM_Foo_sub_sub
    ===========  ===============
    
  • --output-format html: Tables formatted as html table:

    <p>Find class CIM_Foo*</p>
    <table>
    <thead>
    <tr><th>Namespace  </th><th>Classname      </th></tr>
    </thead>
    <tbody>
    <tr><td>root/cimv2 </td><td>CIM_Foo        </td></tr>
    <tr><td>root/cimv2 </td><td>CIM_Foo_sub    </td></tr>
    <tr><td>root/cimv2 </td><td>CIM_Foo_sub2   </td></tr>
    <tr><td>root/cimv2 </td><td>CIM_Foo_sub_sub</td></tr>
    </tbody>
    </table>
    

2.2.4.3. CIM object formats

The output of CIM objects allows multiple formats as follows:

  • --output-format mof: Format for CIM classes, CIM instances, and CIM Parameters.

    MOF is the format used to define and document the CIM models released by the DMTF and SNIA. It textually defines the components and structure and data of CIM elements such as classes, instances, and qualifier declarations:

    instance of CIM_Foo {
       InstanceID = "CIM_Foo1";
       IntegerProp = 1;
    };
    
  • --output-format xml: CIM-XML format for CIM elements such as classes, instances and qualifier declarations. Besides being used as a protocol for WBEM servers, CIM-XML is also an alternative format for representing the CIM models released by the DMTF and SNIA. The XML syntax is defined in the DMTF specification DSP0201.

    This is the format used in the DMTF CIM-XML protocol:

    <VALUE.OBJECTWITHLOCALPATH>
        <LOCALINSTANCEPATH>
            <LOCALNAMESPACEPATH>
                <NAMESPACE NAME="root"/>
                <NAMESPACE NAME="cimv2"/>
            </LOCALNAMESPACEPATH>
            <INSTANCENAME CLASSNAME="CIM_Foo">
                <KEYBINDING NAME="InstanceID">
                    <KEYVALUE VALUETYPE="string">CIM_Foo1</KEYVALUE>
                </KEYBINDING>
            </INSTANCENAME>
        </LOCALINSTANCEPATH>
        <INSTANCE CLASSNAME="CIM_Foo">
            <PROPERTY NAME="InstanceID" PROPAGATED="false" TYPE="string">
                <VALUE>CIM_Foo1</VALUE>
            </PROPERTY>
            <PROPERTY NAME="IntegerProp" PROPAGATED="false" TYPE="uint32">
                <VALUE>1</VALUE>
            </PROPERTY>
        </INSTANCE>
    </VALUE.OBJECTWITHLOCALPATH>
    
  • --output-format repr: Python repr format of the objects.

    This is the structure and data of the pywbem Python objects representing these CIM objects and can be useful in understanding the pywbem interpretation of the CIM objects:

    CIMInstance(classname='CIM_Foo', path=CIMInstanceName(classname='CIM_Foo',
        keybindings=NocaseDict({'InstanceID': 'CIM_Foo1'}), namespace='root/cimv2',
        host=None),
        properties=NocaseDict({
          'InstanceID': CIMProperty(name='InstanceID',
            value='CIM_Foo1', type='string', reference_class=None, embedded_object=None,
            is_array=False, array_size=None, class_origin=None, propagated=False,
            qualifiers=NocaseDict({})),
          'IntegerProp': CIMProperty(name='IntegerProp', value=1, type='uint32',
              reference_class=None, embedded_object=None, is_array=False,
              array_size=None, class_origin=None, propagated=False,
              qualifiers=NocaseDict({}))}), property_list=None,
              qualifiers=NocaseDict({}))
    

    NOTE: The above is output as a single line and has been manually formatted for this documentation.

  • --output-format txt: Python str format of the objects.

    This should be considered the output of last resort as it simply uses the __str__() method of the Python class for each CIM object to output.

    Thus, for example, a class enumerate command of a model with only a single class creates output of the form:

    CIMClass(classname='CIM_Foo', ...)
    

2.2.4.4. ASCII tree format

This output format is an ASCII based output that shows the tree structure of the results of the class tree command. It is the only output format supported by this command, and therefore it is automatically selected and cannot be specified explicitly with the --output-format general option.

$ pywbemcli --mock-server tests/unit/simple_mock_model.mof class tree
root
+-- CIM_Foo
    +-- CIM_Foo_sub
    |   +-- CIM_Foo_sub_sub
    +-- CIM_Foo_sub2

This shows a very simple mock repository with 4 classes where CIM_Foo is the top level in the hierarchy, CIM_Foo_sub and CIM_Foo_sub2 are its subclasses, and CIM_Foo_sub_sub is the subclass of CIM_Foo_sub.

2.2.4.5. Text formats

The TEXT format group outputs the data returned from the command as text to the console without any formatting except for formatting lists and comma separated strings. It is useful for use with data that might be redirected to other commands or output that is simple enough that a single line of output is sufficient.

$ pywbemcli --mock-server tests/unit/testmock/wbemserver_mock.py -o table server namespaces
Server Namespaces:
Namespace Name
----------------
interop

$ pywbemcli --mock-server tests/unit/testmock/wbemserver_mock.py -o text server namespaces
interop

2.2.4.6. Pywbemcli defined logging

Pywbemcli provides logging to either a file or the standard error stream of information passing between the pywbemcli client and a WBEM server using the standard Python logging facility.

Logging is configured and enabled using the --log general option on the commmand line or the PYWBEMCLI_LOG environment variable.

Pywbemcli can log operation calls that send requests to a WBEM server and their responses and the HTTP messages between the pywbemcli client and the WBEM server including both the pywbem APIs and their responses and the HTTP requests and responses.

The default is no logging if the --log option is not specified.

The argument value of the --log option and the value of the PYWBEMCLI_LOG environment variable is a log configuration string with the format defined in the ABNF rule LOG_CONFIG_STRING, below. The log configuration string defines a list of one or more log configurations, each with fields COMPONENT, DESTINATION, and DETAIL:

LOG_CONFIG_STRING := CONFIG [ "," CONFIG ]
CONFIG            := COMPONENT [ "=" DESTINATION [ ":" DETAIL ]]
COMPONENT         := ( "all" / "api" / "http" )
DESTINATION       := ( "stderr" / "file" )
DETAIL            := ( "all" / "path" / "summary" )

For example the following log configuration string logs the pywbem API calls and writes summary information to a log file and the HTTP requests and responses to stderr:

$ pywbemcli --log api=file:summary,http=stderr

The simplest log configuration string to enable logging is all=stderr or all=file.

The COMPONENT field defines the component for which logging is enabled:

  • api - Logs the calls to the pywbem methods that make requests to a WBEM server. This logs both the requests and response including any exceptions generated by error responses from the WBEM server.
  • http - Logs the headers and data for HTTP requests and responses to the WBEM server.
  • all - (Default) Logs both the api and http components.

The DESTINATION field specifies the log destination:

  • stderr - Output log to stderr.
  • file - (default) Log to the pywbemcli log file pywbemcli.log in the current directory. Logs are appended to an existing log file.

The DETAIL component of the log configuration string defines the level of logging information for the api and http components. Because enormous quantities of information can be generated this option exists to limit the amount of information generated. The possible keywords are:

  • all - (Default) Logs the full request including all input parameters and the complete response including all data. Exceptions are fully logged.
  • paths - Logs the full request but only the path component of the api responses. This reduces the data included in the responses. Exceptions are fully logged.
  • summary - Logs the requests but only the count of objects received in the response. Exceptions are fully logged.

The log output is routed to the output defined by DESTINATION and includes the information determined by the COMPONENT and DETAIL fields.

The log output format is:

<Date time>-<Component>.<connection id>-<Direction>:<connection id> <PywbemOperation>(<data>)

For example, logging only of the summary API information would look something like the following:

$ pywbemcli -s http://localhost -u blah -p pw -l api=file:summary class enumerate -o

produces log output for the class enumerate operation in the log file pywbemcli.log as follows showing the input parameters to the pywbem method EnumerateClassName and the number of objects in the response:

2019-07-09 18:27:22,103-pywbem.api.1-27716-Request:1-27716 EnumerateClassNames(ClassName=None, DeepInheritance=False, namespace=None)
2019-07-09 18:27:22,142-pywbem.api.1-27716-Return:1-27716 EnumerateClassNames(list of str; count=103)

2.2.5. Pywbemcli persisted connection definitions

Pywbemcli can manage persisted connection definitions via the connection command group. These connection definitions are persisted in a connections file named .pywbemcli_connections.yaml in the user’s home directory. A connection definition has a name and defines all parameters necessary to connect to a WBEM server. Once defined these connection definitions can be used with the --name general option or in the interactive mode by defining a current connection with the connection select command.

A new persistent connection definition can be created with the connection save command.

At any point in time, pywbemcli can communicate with only a single WBEM server. That is the current connection. In the command mode, this is the WBEM server defined by the general options --server or --mock-server or --name. In the interactive mode, the current connection can be changed within an interactive session using the connection select command so that within a single session, the user can work with multiple WBEM servers (at different points in time).

The following example creates a persisted connection definition, using interactive mode:

$ pywbemcli

pywbemcli> --server http://localhost --user usr1 --password blah connection save testconn

pywbemcli> connection list
WBEM server connections: (#: default, *: current)
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+
| name      | server           | namespace   | user   |   timeout | verify   | mock-server                            |
|-----------+------------------+-------------+--------+-----------+----------+----------------------------------------|
| testconn  | http://localhost | root/cimv2  | usr1   |        30 | True     |                                        |
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+

Since the connection definition is persisted, it is available in command mode as well as in new interactive sessions:

$ pywbemcli connection list
WBEM server connections: (#: default, *: current)
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+
| name      | server           | namespace   | user   |   timeout | verify   | mock-server                            |
|-----------+------------------+-------------+--------+-----------+----------+----------------------------------------|
| testconn  | http://localhost | root/cimv2  | usr1   |        30 | True     |                                        |
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+

$ pywbemcli

pywbemcli> connection list
WBEM server connections: (#: default, *: current)
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+
| name      | server           | namespace   | user   |   timeout | verify   | mock-server                            |
|-----------+------------------+-------------+--------+-----------+----------+----------------------------------------|
| testconn  | http://localhost | root/cimv2  | usr1   |        30 | True     |                                        |
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+

Other connection definitions can be added, this time using command mode:

$ pywbemcli --server http://blah2 --user you --password xxx connection save Ronald

$ pywbemcli connection list
WBEM server connections: (#: default, *: current)
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+
| name      | server           | namespace   | user   |   timeout | verify   | mock-server                            |
|-----------+------------------+-------------+--------+-----------+----------+----------------------------------------|
| Ronald    | http://blah2     | root/cimv2  | you    |        30 | True     |                                        |
| testconn  | http://localhost | root/cimv2  | usr1   |        30 | True     |                                        |
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+

The following example shows how to select current connections in interactive mode. Note the marker * in front of the name, which indicates the current connection. The connection show command when used without a connection name shows the current connection:

$ pywbemcli

pywbemcli> connection select Ronald

pywbemcli> connection list
WBEM server connections: (#: default, *: current)
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+
| name      | server           | namespace   | user   |   timeout | verify   | mock-server                            |
|-----------+------------------+-------------+--------+-----------+----------+----------------------------------------|
| *Ronald   | http://blah2     | root/cimv2  | you    |        30 | True     |                                        |
| testconn  | http://localhost | root/cimv2  | usr1   |        30 | True     |                                        |
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+

pywbemcli> connection show
name: Ronald (current)
  server: http://blah2
  mock-server:
  . . .

pywbemcli> connection select testconn

pywbemcli> connection list
WBEM server connections: (#: default, *: current)
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+
| name      | server           | namespace   | user   |   timeout | verify   | mock-server                            |
|-----------+------------------+-------------+--------+-----------+----------+----------------------------------------|
| Ronald    | http://blah2     | root/cimv2  | you    |        30 | True     |                                        |
| *testconn | http://localhost | root/cimv2  | usr1   |        30 | True     |                                        |
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+

pywbemcli> connection show
name: testconn (current)
  server: http://localhost
  mock-server:
  . . .

pywbemcli> connection show Ronald
name: Ronald
  server: http://blah2
  mock-server:
  . . .

The concept of a current connection that can be selected is useful mostly for the interactive mode. In command mode, the connection specified with one of the -server, --mock-server, or --name general options automatically is considered the current connection, and there is no concept of selecting a current connection other than using these options. Therefore, pywbemcli additionally supports the concept of a persisted default connection.

The following example defines a persisted default connection and then uses it in command mode:

$ pywbemcli connection select Ronald --default
"Ronald" default and current

$ pywbemcli connection list
WBEM server connections: (#: default, *: current)
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+
| name      | server           | namespace   | user   |   timeout | verify   | mock-server                            |
|-----------+------------------+-------------+--------+-----------+----------+----------------------------------------|
| #Ronald   | http://blah2     | root/cimv2  | you    |        30 | True     |                                        |
| testconn  | http://localhost | root/cimv2  | usr1   |        30 | True     |                                        |
+-----------+------------------+-------------+--------+-----------+----------+----------------------------------------+

$ pywbemcli connection show
name: Ronald (default, current)
  server: http://blah2
  mock-server:
  . . .

Connections can be deleted with the connection delete command either with the command argument containing the connection name or with no name provided so pywbemcli presents a list of connections to choose from:

$ pywbemcli connection delete Ronald
Deleted default connection "Ronald".

or:

$ pywbemcli connection delete
Select a connection or CTRL_C to abort.
0: Ronald
1: testconn
Input integer between 0 and 1 or Ctrl-C to exit selection: 0
Deleted default connection "Ronald".