Ansible Reference: Module Utilities
This page documents utilities intended to be helpful when writing Ansible modules in Python.
AnsibleModule
To use this functionality, include from ansible.module_utils.basic import AnsibleModule
in your module.
- class ansible.module_utils.basic.AnsibleModule(argument_spec, bypass_checks=False, no_log=False, mutually_exclusive=None, required_together=None, required_one_of=None, add_file_common_args=False, supports_check_mode=False, required_if=None, required_by=None)
Common code for quickly building an ansible module in Python (although you can write modules with anything that can return JSON).
See Developing Ansible modules for a general introduction and Ansible module architecture for more detailed explanation.
- add_path_info(kwargs)
for results that are files, supplement the info about the file in the return path with stats about the file path.
- atomic_move(src, dest, unsafe_writes=False)
atomically move src to dest, copying attributes from dest, returns true on success it uses os.rename to ensure this as it is an atomic operation, rest of the function is to work around limitations, corner cases and ensure selinux context is saved if possible
- backup_local(fn)
make a date-marked backup of the specified file, return True or False on success or failure
- boolean(arg)
Convert the argument to a boolean
- digest_from_file(filename, algorithm)
Return hex digest of local file for a digest_method specified by name, or None if file is not present.
- exit_json(**kwargs)
return from the module, without error
- fail_json(msg, **kwargs)
return from the module, with an error message
- find_mount_point(path)
Takes a path and returns it’s mount point
- Parameters
path – a string type with a filesystem path
- Returns
the path to the mount point as a text type
- get_bin_path(arg, required=False, opt_dirs=None)
Find system executable in PATH.
- Parameters
arg – The executable to find.
required – if executable is not found and required is
True
, fail_jsonopt_dirs – optional list of directories to search in addition to
PATH
- Returns
if found return full path; otherwise return None
- is_executable(path)
is the given path executable?
- Parameters
path – The path of the file to check.
Limitations:
Does not account for FSACLs.
Most times we really want to know “Can the current user execute this file”. This function does not tell us that, only if any execute bit is set.
- is_special_selinux_path(path)
Returns a tuple containing (True, selinux_context) if the given path is on a NFS or other ‘special’ fs mount point, otherwise the return will be (False, None).
- load_file_common_arguments(params, path=None)
many modules deal with files, this encapsulates common options that the file module accepts such that it is directly available to all modules and they can share code.
Allows to overwrite the path/dest module argument by providing path.
- md5(filename)
Return MD5 hex digest of local file using digest_from_file().
- Do not use this function unless you have no other choice for:
Optional backwards compatibility
Compatibility with a third party protocol
This function will not work on systems complying with FIPS-140-2.
Most uses of this function can use the module.sha1 function instead.
- preserved_copy(src, dest)
Copy a file with preserved ownership, permissions and context
- run_command(args, check_rc=False, close_fds=True, executable=None, data=None, binary_data=False, path_prefix=None, cwd=None, use_unsafe_shell=False, prompt_regex=None, environ_update=None, umask=None, encoding='utf-8', errors='surrogate_or_strict', expand_user_and_vars=True, pass_fds=None, before_communicate_callback=None, ignore_invalid_cwd=True)
Execute a command, returns rc, stdout, and stderr.
- Parameters
args – is the command to run * If args is a list, the command will be run with shell=False. * If args is a string and use_unsafe_shell=False it will split args to a list and run with shell=False * If args is a string and use_unsafe_shell=True it runs with shell=True.
- Kw check_rc
Whether to call fail_json in case of non zero RC. Default False
- Kw close_fds
See documentation for subprocess.Popen(). Default True
- Kw executable
See documentation for subprocess.Popen(). Default None
- Kw data
If given, information to write to the stdin of the command
- Kw binary_data
If False, append a newline to the data. Default False
- Kw path_prefix
If given, additional path to find the command in. This adds to the PATH environment variable so helper commands in the same directory can also be found
- Kw cwd
If given, working directory to run the command inside
- Kw use_unsafe_shell
See args parameter. Default False
- Kw prompt_regex
Regex string (not a compiled regex) which can be used to detect prompts in the stdout which would otherwise cause the execution to hang (especially if no input data is specified)
- Kw environ_update
dictionary to update os.environ with
- Kw umask
Umask to be used when running the command. Default None
- Kw encoding
Since we return native strings, on python3 we need to know the encoding to use to transform from bytes to text. If you want to always get bytes back, use encoding=None. The default is “utf-8”. This does not affect transformation of strings given as args.
- Kw errors
Since we return native strings, on python3 we need to transform stdout and stderr from bytes to text. If the bytes are undecodable in the
encoding
specified, then use this error handler to deal with them. The default issurrogate_or_strict
which means that the bytes will be decoded using the surrogateescape error handler if available (available on all python3 versions we support) otherwise a UnicodeError traceback will be raised. This does not affect transformations of strings given as args.- Kw expand_user_and_vars
When
use_unsafe_shell=False
this argument dictates whether~
is expanded in paths and environment variables are expanded before running the command. WhenTrue
a string such as$SHELL
will be expanded regardless of escaping. WhenFalse
anduse_unsafe_shell=False
no path or variable expansion will be done.- Kw pass_fds
When running on Python 3 this argument dictates which file descriptors should be passed to an underlying
Popen
constructor. On Python 2, this will setclose_fds
to False.- Kw before_communicate_callback
This function will be called after
Popen
object will be created but before communicating to the process. (Popen
object will be passed to callback as a first argument)- Kw ignore_invalid_cwd
This flag indicates whether an invalid
cwd
(non-existent or not a directory) should be ignored or should raise an exception.- Returns
A 3-tuple of return code (integer), stdout (native string), and stderr (native string). On python2, stdout and stderr are both byte strings. On python3, stdout and stderr are text strings converted according to the encoding and errors parameters. If you want byte strings on python3, use encoding=None to turn decoding to text off.
- sha1(filename)
Return SHA1 hex digest of local file using digest_from_file().
- sha256(filename)
Return SHA-256 hex digest of local file using digest_from_file().
Basic
To use this functionality, include import ansible.module_utils.basic
in your module.
- ansible.module_utils.basic.get_all_subclasses(cls)
Deprecated: Use ansible.module_utils.common._utils.get_all_subclasses instead
- ansible.module_utils.basic.get_platform()
Deprecated Use
platform.system()
directly.- Returns
Name of the platform the module is running on in a native string
Returns a native string that labels the platform (“Linux”, “Solaris”, etc). Currently, this is the result of calling
platform.system()
.
- ansible.module_utils.basic.heuristic_log_sanitize(data, no_log_values=None)
Remove strings that look like passwords from log messages
- ansible.module_utils.basic.load_platform_subclass(cls, *args, **kwargs)
Deprecated: Use ansible.module_utils.common.sys_info.get_platform_subclass instead
Argument Spec
Classes and functions for validating parameters against an argument spec.
ArgumentSpecValidator
- class ansible.module_utils.common.arg_spec.ArgumentSpecValidator(argument_spec, mutually_exclusive=None, required_together=None, required_one_of=None, required_if=None, required_by=None)
Argument spec validation class
Creates a validator based on the
argument_spec
that can be used to validate a number of parameters using thevalidate()
method.- Parameters
argument_spec (dict[str, dict]) – Specification of valid parameters and their type. May include nested argument specs.
mutually_exclusive (list[str] or list[list[str]]) – List or list of lists of terms that should not be provided together.
required_together (list[list[str]]) – List of lists of terms that are required together.
required_one_of (list[list[str]]) – List of lists of terms, one of which in each list is required.
required_if (list) – List of lists of
[parameter, value, [parameters]]
where one of[parameters]
is required ifparameter == value
.required_by (dict[str, list[str]]) – Dictionary of parameter names that contain a list of parameters required by each key in the dictionary.
- validate(parameters, *args, **kwargs)
Validate
parameters
against argument spec.Error messages in the
ValidationResult
may contain no_log values and should be sanitized withsanitize_keys()
before logging or displaying.- Parameters
parameters (dict[str, dict]) – Parameters to validate against the argument spec
- Returns
ValidationResult
containing validated parameters.- Simple Example
argument_spec = { 'name': {'type': 'str'}, 'age': {'type': 'int'}, } parameters = { 'name': 'bo', 'age': '42', } validator = ArgumentSpecValidator(argument_spec) result = validator.validate(parameters) if result.error_messages: sys.exit("Validation failed: {0}".format(", ".join(result.error_messages)) valid_params = result.validated_parameters
ValidationResult
- class ansible.module_utils.common.arg_spec.ValidationResult(parameters)
Result of argument spec validation.
This is the object returned by
ArgumentSpecValidator.validate()
containing the validated parameters and any errors.- Parameters
parameters (dict) – Terms to be validated and coerced to the correct type.
- errors
AnsibleValidationErrorMultiple
containing allAnsibleValidationError
objects if there were any failures during validation.
- property validated_parameters
Validated and coerced parameters.
Parameters
- ansible.module_utils.common.parameters.DEFAULT_TYPE_VALIDATORS
dict
of type names, such as'str'
, and the default function used to check that type,check_type_str()
in this case.
- ansible.module_utils.common.parameters.env_fallback(*args, **kwargs)
Load value from environment variable
- ansible.module_utils.common.parameters.remove_values(value, no_log_strings)
Remove strings in
no_log_strings
from value.If value is a container type, then remove a lot more.
Use of
deferred_removals
exists, rather than a pure recursive solution, because of the potential to hit the maximum recursion depth when dealing with large amounts of data (see issue #24560).
- ansible.module_utils.common.parameters.sanitize_keys(obj, no_log_strings, ignore_keys=frozenset({}))
Sanitize the keys in a container object by removing
no_log
values from key names.This is a companion function to the
remove_values()
function. Similar to that function, we make use ofdeferred_removals
to avoid hitting maximum recursion depth in cases of large data structures.- Parameters
obj – The container object to sanitize. Non-container objects are returned unmodified.
no_log_strings – A set of string values we do not want logged.
ignore_keys – A set of string values of keys to not sanitize.
- Returns
An object with sanitized keys.
Validation
Standalone functions for validating various parameter types.
- ansible.module_utils.common.validation.check_missing_parameters(parameters, required_parameters=None)
This is for checking for required params when we can not check via argspec because we need more information than is simply given in the argspec.
Raises
TypeError
if any required parameters are missing- Parameters
parameters – Dictionary of parameters
required_parameters – List of parameters to look for in the given parameters.
- Returns
Empty list or raises
TypeError
if the check fails.
- ansible.module_utils.common.validation.check_mutually_exclusive(terms, parameters, options_context=None)
Check mutually exclusive terms against argument parameters
Accepts a single list or list of lists that are groups of terms that should be mutually exclusive with one another
- Parameters
terms – List of mutually exclusive parameters
parameters – Dictionary of parameters
- Returns
Empty list or raises
TypeError
if the check fails.
- ansible.module_utils.common.validation.check_required_arguments(argument_spec, parameters, options_context=None)
Check all parameters in argument_spec and return a list of parameters that are required but not present in parameters.
Raises
TypeError
if the check fails- Parameters
argument_spec – Argument spec dictionary containing all parameters and their specification
parameters – Dictionary of parameters
- Returns
Empty list or raises
TypeError
if the check fails.
- ansible.module_utils.common.validation.check_required_by(requirements, parameters, options_context=None)
For each key in requirements, check the corresponding list to see if they exist in parameters.
Accepts a single string or list of values for each key.
- Parameters
requirements – Dictionary of requirements
parameters – Dictionary of parameters
- Returns
Empty dictionary or raises
TypeError
if the
- ansible.module_utils.common.validation.check_required_if(requirements, parameters, options_context=None)
Check parameters that are conditionally required
Raises
TypeError
if the check fails- Parameters
requirements – List of lists specifying a parameter, value, parameters required when the given parameter is the specified value, and optionally a boolean indicating any or all parameters are required.
- Example
required_if=[ ['state', 'present', ('path',), True], ['someint', 99, ('bool_param', 'string_param')], ]
- Parameters
parameters – Dictionary of parameters
- Returns
Empty list or raises
TypeError
if the check fails. The results attribute of the exception contains a list of dictionaries. Each dictionary is the result of evaluating each item in requirements. Each return dictionary contains the following keys:- key missing
List of parameters that are required but missing
- key requires
’any’ or ‘all’
- key parameter
Parameter name that has the requirement
- key value
Original value of the parameter
- key requirements
Original required parameters
- Example
[ { 'parameter': 'someint', 'value': 99 'requirements': ('bool_param', 'string_param'), 'missing': ['string_param'], 'requires': 'all', } ]
- ansible.module_utils.common.validation.check_required_one_of(terms, parameters, options_context=None)
Check each list of terms to ensure at least one exists in the given module parameters
Accepts a list of lists or tuples
- Parameters
terms – List of lists of terms to check. For each list of terms, at least one is required.
parameters – Dictionary of parameters
options_context – List of strings of parent key names if
terms
are in a sub spec.
- Returns
Empty list or raises
TypeError
if the check fails.
- ansible.module_utils.common.validation.check_required_together(terms, parameters, options_context=None)
Check each list of terms to ensure every parameter in each list exists in the given parameters.
Accepts a list of lists or tuples.
- Parameters
terms – List of lists of terms to check. Each list should include parameters that are all required when at least one is specified in the parameters.
parameters – Dictionary of parameters
- Returns
Empty list or raises
TypeError
if the check fails.
- ansible.module_utils.common.validation.check_type_bits(value)
Convert a human-readable string bits value to bits in integer.
Example:
check_type_bits('1Mb')
returns integer 1048576.Raises
TypeError
if unable to covert the value.
- ansible.module_utils.common.validation.check_type_bool(value)
Verify that the value is a bool or convert it to a bool and return it.
Raises
TypeError
if unable to convert to a bool- Parameters
value – String, int, or float to convert to bool. Valid booleans include: ‘1’, ‘on’, 1, ‘0’, 0, ‘n’, ‘f’, ‘false’, ‘true’, ‘y’, ‘t’, ‘yes’, ‘no’, ‘off’
- Returns
Boolean True or False
- ansible.module_utils.common.validation.check_type_bytes(value)
Convert a human-readable string value to bytes
Raises
TypeError
if unable to covert the value
- ansible.module_utils.common.validation.check_type_dict(value)
Verify that value is a dict or convert it to a dict and return it.
Raises
TypeError
if unable to convert to a dict- Parameters
value – Dict or string to convert to a dict. Accepts
k1=v2, k2=v2
.- Returns
value converted to a dictionary
- ansible.module_utils.common.validation.check_type_float(value)
Verify that value is a float or convert it to a float and return it
Raises
TypeError
if unable to convert to a float- Parameters
value – float, int, str, or bytes to verify or convert and return.
- Returns
float of given value.
- ansible.module_utils.common.validation.check_type_int(value)
Verify that the value is an integer and return it or convert the value to an integer and return it
Raises
TypeError
if unable to convert to an int- Parameters
value – String or int to convert of verify
- Returns
int of given value
- ansible.module_utils.common.validation.check_type_jsonarg(value)
Return a jsonified string. Sometimes the controller turns a json string into a dict/list so transform it back into json here
Raises
TypeError
if unable to covert the value
- ansible.module_utils.common.validation.check_type_list(value)
Verify that the value is a list or convert to a list
A comma separated string will be split into a list. Raises a
TypeError
if unable to convert to a list.- Parameters
value – Value to validate or convert to a list
- Returns
Original value if it is already a list, single item list if a float, int, or string without commas, or a multi-item list if a comma-delimited string.
- ansible.module_utils.common.validation.check_type_path(value)
Verify the provided value is a string or convert it to a string, then return the expanded path
- ansible.module_utils.common.validation.check_type_raw(value)
Returns the raw value
- ansible.module_utils.common.validation.check_type_str(value, allow_conversion=True, param=None, prefix='')
Verify that the value is a string or convert to a string.
Since unexpected changes can sometimes happen when converting to a string,
allow_conversion
controls whether or not the value will be converted or a TypeError will be raised if the value is not a string and would be converted- Parameters
value – Value to validate or convert to a string
allow_conversion – Whether to convert the string and return it or raise a TypeError
- Returns
Original value if it is a string, the value converted to a string if allow_conversion=True, or raises a TypeError if allow_conversion=False.
- ansible.module_utils.common.validation.count_terms(terms, parameters)
Count the number of occurrences of a key in a given dictionary
- Parameters
terms – String or iterable of values to check
parameters – Dictionary of parameters
- Returns
An integer that is the number of occurrences of the terms values in the provided dictionary.
Errors
- exception ansible.module_utils.errors.AnsibleFallbackNotFound
Fallback validator was not found
- exception ansible.module_utils.errors.AnsibleValidationError(message)
Single argument spec validation error
- error_message
The error message passed in when the exception was raised.
- property msg
The error message passed in when the exception was raised.
- exception ansible.module_utils.errors.AnsibleValidationErrorMultiple(errors=None)
Multiple argument spec validation errors
- errors
list
ofAnsibleValidationError
objects
- property msg
The first message from the first error in
errors
.
- append(error)
Append a new error to
self.errors
.Only
AnsibleValidationError
should be added.
- extend(errors)
Append each item in
errors
toself.errors
. OnlyAnsibleValidationError
should be added.
- exception ansible.module_utils.errors.AliasError(message)
Error handling aliases
- exception ansible.module_utils.errors.ArgumentTypeError(message)
Error with parameter type
- exception ansible.module_utils.errors.ArgumentValueError(message)
Error with parameter value
- exception ansible.module_utils.errors.ElementError(message)
Error when validating elements
- exception ansible.module_utils.errors.MutuallyExclusiveError(message)
Mutually exclusive parameters were supplied
- exception ansible.module_utils.errors.NoLogError(message)
Error converting no_log values
- exception ansible.module_utils.errors.RequiredByError(message)
Error with parameters that are required by other parameters
- exception ansible.module_utils.errors.RequiredDefaultError(message)
A required parameter was assigned a default value
- exception ansible.module_utils.errors.RequiredError(message)
Missing a required parameter
- exception ansible.module_utils.errors.RequiredIfError(message)
Error with conditionally required parameters
- exception ansible.module_utils.errors.RequiredOneOfError(message)
Error with parameters where at least one is required
- exception ansible.module_utils.errors.RequiredTogetherError(message)
Error with parameters that are required together
- exception ansible.module_utils.errors.SubParameterTypeError(message)
Incorrect type for subparameter
- exception ansible.module_utils.errors.UnsupportedError(message)
Unsupported parameters were supplied