### Attribute Types
class Types:
+ """ Allowed types for the Attribute value
+ """
String = "STRING"
Bool = "BOOL"
Enumerate = "ENUM"
### Attribute Flags
class Flags:
- """ Differents flags to characterize an attribute
-
+ """ Flags to characterize the scope of an Attribute
"""
- # Attribute can be modified by the user
- NoFlags = 0x00
- # Attribute is not modifiable by the user
- ReadOnly = 0x01
- # Attribute is not modifiable by the user during runtime
- ExecReadOnly = 0x02
- # Attribute is an access credential
- Credential = 0x04
+ # Attribute value can not be read (it is hidden to the user)
+ NoRead = 1 # 1
+
+ # Attribute value can not be modified (it is not editable by the user)
+ NoWrite = 1 << 1 # 2
+
+ # Attribute value can be modified only before deployment
+ Design = 1 << 2 # 4
+
+ # Attribute value will be used at deployment time for initial configuration
+ Construct = 1 << 3 # 8
+
+ # Attribute provides credentials to access resources
+ Credential = 1 << 4 | Design # 16 + 4
+
# Attribute is a filter used to discover resources
- Filter = 0x08
+ Filter = 1 << 5 | Design # 32 + 4
+
+ # Attribute Flag is reserved for internal RM usage (i.e. should be
+ # transparent to the user)
+ Reserved = 1 << 6 # 64
+
+ # Attribute global is set to all resources of rtype
+ Global = 1 << 7 # 128
+
class Attribute(object):
+ """ An Attribute exposes a configuration parameter of a resource
"""
- .. class:: Class Args :
-
- :param name: Name of the attribute
+
+ def __init__(self, name, help, type = Types.String,
+ flags = None, default = None, allowed = None,
+ range = None, set_hook = None):
+ """
+ :param name: Name of the Attribute
:type name: str
- :param help: Help about the attribute
+
+ :param help: Description of the Attribute
:type help: str
- :param type: type of the attribute
+
+ :param type: The type expected for the Attribute value.
+ Should be one of Attribute.Types
:type type: str
- :param flags: Help about the attribute
- :type flags: str
- :param default: Default value of the attribute
- :type default: str
- :param allowed: Allowed value for this attribute
- :type allowed: str
- :param range: Range of the attribute
- :type range: str
- :param set_hook: hook that is related with this attribute
- :type set_hook: str
+
+ :param flags: Defines Attribute behavior (i.e. whether it is read-only,
+ read and write, etc). This parameter must take its values from
+ Attribute.Flags. Flags values can be bitwised
+ :type flags: hex
+
+ :param default: Default value for the Attribute
+ :type default: Depends on the type of Attribute
+
+ :param allowed: List of values that the Attribute can take.
+ This parameter is only meaningful for Enumerate type Attributes
+ :type allowed: list
+
+ :param range: (max, min) tuple with range of possible values for
+ Attributes.
+ This parameter is only meaningful for Integer or Double type
+ Attributes
+ :type range: (int, int) or (float, float)
+
+ :param set_hook: Function that will be executed whenever a new
+ value is set for the Attribute.
+ :type set_hook: function
"""
- def __init__(self, name, help, type = Types.String,
- flags = Flags.NoFlags, default = None, allowed = None,
- range = None, set_hook = None):
self._name = name
self._help = help
self._type = type
- self._flags = flags
+ self._flags = flags or 0
self._allowed = allowed
self._range = range
self._default = self._value = default
@property
def name(self):
- """ Returns the name of the attribute """
+ """ Returns the name of the Attribute """
return self._name
@property
def default(self):
- """ Returns the default value of the attribute """
+ """ Returns the default value of the Attribute """
return self._default
@property
def type(self):
- """ Returns the type of the attribute """
+ """ Returns the type of the Attribute """
return self._type
@property
def help(self):
- """ Returns the help of the attribute """
+ """ Returns the description of the Attribute """
return self._help
@property
def flags(self):
- """ Returns the flags of the attribute """
+ """ Returns the flags of the Attribute """
return self._flags
@property
def allowed(self):
- """ Returns the allowed value for this attribute """
+ """ Returns the set of allowed values for the Attribute """
return self._allowed
@property
def range(self):
- """ Returns the range of the attribute """
+ """ Returns the range of allowed numerical values for the Attribute """
return self._range
def has_flag(self, flag):
- """ Returns true if the attribute has the flag 'flag'
+ """ Returns True if the Attribute has the flag 'flag'
- :param flag: Flag that need to be ckecked
+ :param flag: Flag to be checked
:type flag: Flags
"""
return (self._flags & flag) == flag
def get_value(self):
- """ Returns the value of the attribute """
+ """ Returns the value of the Attribute """
return self._value
def set_value(self, value):
- """ Change the value of the attribute after checking the type """
+ """ Configure a new value for the Attribute """
valid = True
if self.type == Types.Enumerate:
if self.type in [Types.Double, Types.Integer] and self.range:
(min, max) = self.range
+
+ value = float(value)
+
valid = (value >= min and value <= max)
valid = valid and self.is_valid_value(value)
adequate validation"""
return True
+ @property
+ def has_changed(self):
+ """ Returns True if the value has changed from the default """
+ return self.value != self.default
+