182 lines
5.3 KiB
Plaintext
182 lines
5.3 KiB
Plaintext
.. default-role:: literal
|
|
|
|
Configuration status
|
|
======================
|
|
|
|
:module: :api:`config.py`
|
|
:tests: - :api:`test_option_owner.py`
|
|
- :api:`test_option_type.py`
|
|
- :api:`test_option_default.py`
|
|
|
|
Available configuration statuses
|
|
----------------------------------
|
|
|
|
These configuration statuses corresponds to specific global attributes :
|
|
|
|
**read write status**
|
|
|
|
The configuration can be accessed by `__get__` and `__set__`
|
|
properties, except for the `hidden` configuration options but, yes, it is
|
|
possible to modify a disabled option.
|
|
|
|
To enable read-write status, call
|
|
:api:`config.Config.cfgimpl_read_write()`
|
|
|
|
**read only status**
|
|
|
|
The whole configuration is `frozen`, that is modifiying a value is
|
|
forbidden. We can access to a configuration option only with the
|
|
`__getattr__` property.
|
|
|
|
The configuration has not an access to the hidden options
|
|
but can read the disabled options.
|
|
|
|
To enable read only status, call :api:`config.Config.cfgimpl_read_only()`
|
|
|
|
.. csv-table:: **Configuration's statuses summary**
|
|
:header: " ", "Hidden", "Disabled"
|
|
|
|
"read only status", `False`, `True`
|
|
"read-write status", `True`, `False`
|
|
|
|
Freezing a configuration
|
|
---------------------------
|
|
|
|
It is possible to *freeze* a single `Option` object with
|
|
:api:`option.Option.freeze()`. If you try to modify a frozen option, it
|
|
raises a `TypeError: trying to change a frozen option object`.
|
|
|
|
At the configuration level, :api:`config.Config.cfgimpl_freeze()` freeze
|
|
the whole configuration options.
|
|
|
|
- :api:`test_option_type.test_freeze_one_option()`
|
|
- :api:`test_option_type.test_frozen_value()`
|
|
- :api:`test_option_type.test_freeze()`
|
|
|
|
|
|
Restricted access to an `Option()`
|
|
-----------------------------------
|
|
|
|
Configuration options access statuses are defined at configuration level
|
|
that corresponds to theses :api:`option.Option()`'s attribute:
|
|
|
|
**hidden**
|
|
|
|
This means that an option raises an `HiddenOptionError` if we try to access
|
|
the value of the option.
|
|
|
|
See `hide()` or `show()` in `Option()` that comes from
|
|
:api:`option.HiddenBaseType`
|
|
|
|
corresponding convenience API provided:
|
|
|
|
`hide()`:
|
|
set the `hidden` attribute to `True`
|
|
|
|
`show()`:
|
|
set the `hidden` attribute to `False`
|
|
|
|
**disabled**
|
|
|
|
This means that an option *doesn't exists* (doesn't say anything
|
|
much more thant an `AttibuteAccess` error)
|
|
|
|
See in :api:`option.DisabledBaseType` the origins of
|
|
`Option.enable()` or `Option.disable()`
|
|
|
|
corresponding convenience API provided:
|
|
|
|
`disable()`:
|
|
set the `disabled` attribute to `True`
|
|
|
|
`enable()`:
|
|
set the `disabled` attribute to `False`
|
|
|
|
mode
|
|
|
|
a mode is `normal` or `expert`, just a category of `Option()` or
|
|
group wich determines if an option is easy to choose or not,
|
|
available methods are:
|
|
|
|
`get_mode()`:
|
|
returns the current mode
|
|
|
|
`set_mode(mode)`:
|
|
sets a new mode
|
|
|
|
see it in :api:`option.ModeBaseType`
|
|
|
|
Value owners
|
|
-------------
|
|
|
|
Every configuration option has a **owner**. When the option is
|
|
instanciated, the owner is `default` because a default value has been
|
|
set (including `None`, take a look at the tests).
|
|
|
|
The `value_owner` is the man who did it. Yes, the man who changed the value of the
|
|
configuration option.
|
|
|
|
- At the instance of the `Config` object, the value owner is `default` because
|
|
the default values are set at the instance of the configuration option object,
|
|
|
|
::
|
|
|
|
# let's expect there is an option named 'name'
|
|
config = Config(descr, bool=False)
|
|
# the override method has been called
|
|
config._cfgimpl_value_owners['name'] == 'default'
|
|
|
|
- at the modification of an option, the owner is `default_owner`, (which is `user`)
|
|
|
|
::
|
|
|
|
# modification of the value by attribute access
|
|
config.gc.dummy = True
|
|
assert config.gc._cfgimpl_value_owners['dummy'] == 'user'
|
|
assert config._cfgimpl_values['gc']._cfgimpl_value_owners['dummy'] == 'user'
|
|
|
|
- the default owner can be set with the `set_owner()` method
|
|
|
|
::
|
|
|
|
config.set_owner('spam')
|
|
config.set(dummy=True)
|
|
assert config.gc._cfgimpl_value_owners['dummy'] == 'spam'
|
|
assert config._cfgimpl_values['gc']._cfgimpl_value_owners['dummy'] == 'spam'
|
|
|
|
Special owners
|
|
---------------
|
|
|
|
If the owner of a configuration option is `auto` or `fill` the behavior of the
|
|
access of the value changes. In fact, there is nothing in the value.
|
|
The value comes from somewhere else (typically, it is calculated by the
|
|
operation system).
|
|
|
|
**auto**
|
|
|
|
This means that it is a calculated value and therefore automatically
|
|
protected it cannot be modified by attribute access once the owner
|
|
is `auto`.
|
|
|
|
The configuration option is hidden and a fonction in a specific
|
|
library is called for the computation of the value.
|
|
|
|
**fill**
|
|
|
|
if the configuration option has a default value, the default is
|
|
returned, otherwise the value is calculated
|
|
|
|
The default values behavior
|
|
----------------------------
|
|
|
|
Configuration options have default values that are stored in the
|
|
`Option()` object itself. Default values, the `default`, can be set in
|
|
various ways.
|
|
|
|
.. FIXME : ADD DETAILS HERE
|
|
|
|
If a default value is modified by overriding it, not only the value of
|
|
the option resets to the default that is proposed, but the owner is
|
|
modified too, it is reseted to `default`.
|
|
|