Allow user to override Platform validation checks. Fixes #61.

In support of this:
- add UI.validate_value() API
- Platform instances cache check results to avoid nagging the user
  over and over and over again about the same change from various
  points in COT runtime.

CHANGELOG.rst

@@ -8,14 +8,51 @@ This project adheres to `Semantic Versioning`_.
 
 **Changed**
 
-- Moved the ``to_string`` function from ``COT.data_validation`` to
-  ``COT.ui_shared``.
-- ``COT.ovf.ovf.byte_string`` has been moved and renamed to
-  ``COT.ui_shared.pretty_bytes``.
-- ``COT.ovf.ovf.byte_count`` has been moved and renamed to
-  ``COT.ovf.utilities.programmatic_bytes_to_int``.
-- ``COT.ovf.ovf.factor_bytes`` has been moved and renamed to
-  ``COT.ovf.utilities.int_bytes_to_programmatic_units``.
+- With ``cot edit-hardware``, the platform hardware validation is no longer
+  a hard limit. Instead, if a value appears to be invalid, the user will be
+  warned about the validation failure and given the option to continue or
+  abort (`#61`_).
+  ``cot --force ...``, as usual, can be used to auto-continue without prompting.
+- Lots of API changes:
+
+  - Moved the ``to_string`` function from ``COT.data_validation`` to
+    ``COT.ui_shared``.
+  - Function ``COT.deploy_esxi.get_object_from_connection`` is now method
+    ``PyVmomiVMReconfigSpec.lookup_object``.
+
+  - COT.disks module:
+
+    - Function ``create_disk`` is now split into class methods
+      ``DiskRepresentation.for_new_file`` (creates the disk file and returns a
+      corresponding ``DiskRepresentation`` instance) and
+      ``DiskRepresentation.create_file`` (creates disk file only).
+    - Function ``convert_disk`` is now class method
+      ``DiskRepresentation.convert_to``
+    - Function ``disk_representation_from_file`` is now
+      class method ``DiskRepresentation.from_file``
+    - The ``DiskRepresentation`` constructor now only takes the path to a file
+      as input - if you want to create a new file, use
+      ``DiskRepresentation.for_new_file`` instead of calling the
+      constructor directly.
+
+  - COT.ovf module:
+
+    - ``COT.ovf.ovf.byte_string`` has been moved and renamed to
+      ``COT.ui_shared.pretty_bytes``.
+    - ``COT.ovf.ovf.byte_count`` has been moved and renamed to
+      ``COT.ovf.utilities.programmatic_bytes_to_int``.
+    - ``COT.ovf.ovf.factor_bytes`` has been moved and renamed to
+      ``COT.ovf.utilities.int_bytes_to_programmatic_units``.
+
+  - COT.platforms module:
+
+    - Class ``GenericPlatform`` is now ``Platform``.
+    - Function ``platform_from_product_class`` is now class method
+      ``Platform.for_product_string`` and returns an instance
+      of a ``Platform`` class rather than the class object itself.
+    - Most ``Platform`` APIs are now instance methods instead of
+      class methods.
+    - Function ``is_known_product_class`` has been removed.
 
 `1.9.1`_ - 2017-02-21
 ---------------------
@@ -633,6 +670,7 @@ Initial public release.
 .. _#58: https://github.com/glennmatthews/cot/issues/58
 .. _#59: https://github.com/glennmatthews/cot/issues/59
 .. _#60: https://github.com/glennmatthews/cot/issues/60
+.. _#61: https://github.com/glennmatthews/cot/issues/61
 
 .. _Semantic Versioning: http://semver.org/
 .. _`PEP 8`: https://www.python.org/dev/peps/pep-0008/

COT/add_disk.py

@@ -393,7 +393,7 @@ def guess_controller_type(platform, ctrl_item, drive_type):
     """If a controller type wasn't specified, try to guess from context.
 
     Args:
-      platform (Platform): Platform class to guess controller for
+      platform (Platform): Platform instance to guess controller for
       ctrl_item (object): Any known controller object, or None
       drive_type (str): "cdrom" or "harddisk"
     Returns:
@@ -405,7 +405,7 @@ def guess_controller_type(platform, ctrl_item, drive_type):
       ::
 
         >>> from COT.platforms import Platform
-        >>> guess_controller_type(Platform, None, 'harddisk')
+        >>> guess_controller_type(Platform(), None, 'harddisk')
         'ide'
     """
     if ctrl_item is None:
@@ -416,7 +416,7 @@ def guess_controller_type(platform, ctrl_item, drive_type):
         ctrl_type = platform.controller_type_for_device(drive_type)
         logger.warning("Guessing controller type should be %s "
                        "based on disk drive type %s and platform %s",
-                       ctrl_type, drive_type, platform.__name__)
+                       ctrl_type, drive_type, platform)
     else:
         ctrl_type = ctrl_item.hardware_type
         if ctrl_type != 'ide' and ctrl_type != 'scsi':

COT/data_validation.py

@@ -57,6 +57,7 @@
 
 import hashlib
 import re
+from collections import namedtuple
 from distutils.util import strtobool
 
 from COT.ui_shared import to_string
@@ -443,7 +444,7 @@ def no_whitespace(string):
 
 def validate_int(string,
                  minimum=None, maximum=None,
-                 label="input"):
+                 label=None):
     """Parser helper function for validating integer arguments in a range.
 
     Args:
@@ -476,6 +477,8 @@ def validate_int(string,
         ...     print(e)
         Value '100' for x is too high - must be at most 10
     """
+    if label is None:
+        label = "input"
     try:
         i = int(string)
     except ValueError:
@@ -487,13 +490,14 @@ def validate_int(string,
     return i
 
 
-def non_negative_int(string):
+def non_negative_int(string, label=None):
     """Parser helper function for integer arguments that must be 0 or more.
 
     Alias for :func:`validate_int` setting :attr:`minimum` to 0.
 
     Args:
       string (str): String to validate.
+      label (str): Label to include in any errors raised
     Returns:
       int: Validated integer value
     Raises:
@@ -512,16 +516,17 @@ def non_negative_int(string):
         ...     print(e)
         Value '-1' for input is too low - must be at least 0
     """
-    return validate_int(string, minimum=0)
+    return validate_int(string, minimum=0, label=label)
 
 
-def positive_int(string):
+def positive_int(string, label=None):
     """Parser helper function for integer arguments that must be 1 or more.
 
     Alias for :func:`validate_int` setting :attr:`minimum` to 1.
 
     Args:
       string (str): String to validate.
+      label (str): Label to include in any errors raised
     Returns:
       int: Validated integer value
     Raises:
@@ -538,7 +543,7 @@ def positive_int(string):
         ...     print(e)
         Value '0' for input is too low - must be at least 1
     """
-    return validate_int(string, minimum=1)
+    return validate_int(string, minimum=1, label=label)
 
 
 def truth_value(value):
@@ -582,6 +587,10 @@ def truth_value(value):
         )
 
 
+ValidRange = namedtuple('ValidRange', ['minimum', 'maximum'])
+"""Simple helper class representing a range of valid values."""
+
+
 # Some handy exception and error types we can throw
 class ValueMismatchError(ValueError):
     """Values which were expected to be equal turned out to be not equal."""

COT/edit_hardware.py

@@ -130,7 +130,7 @@ def cpus(self, value):
             raise InvalidInputError("cpus value must be an integer")
         if value < 1:
             raise InvalidInputError("CPU count must be at least 1")
-        self.vm.platform.validate_cpu_count(value)
+        self.ui.validate_value(self.vm.platform.validate_cpu_count, value)
         self._cpus = value
 
     @property
@@ -169,7 +169,8 @@ def memory(self, value):
                 logger.warning("Memory units not specified, "
                                "guessing '%s' means '%s MiB'",
                                mem_value, mem_value)
-        self.vm.platform.validate_memory_amount(mem_value)
+        self.ui.validate_value(self.vm.platform.validate_memory_amount,
+                               mem_value)
         self._memory = mem_value
 
     @property
@@ -183,7 +184,8 @@ def nics(self, value):
             value = int(value)
         except ValueError:
             raise InvalidInputError("nics value must be an integer")
-        self.vm.platform.validate_nic_count(value)
+        non_negative_int(value, label="nics")
+        self.ui.validate_value(self.vm.platform.validate_nic_count, value)
         self._nics = value
 
     @property
@@ -215,7 +217,7 @@ def nic_types(self):
     @nic_types.setter
     def nic_types(self, value):
         value = [canonicalize_nic_subtype(v) for v in value]
-        self.vm.platform.validate_nic_types(value)
+        self.ui.validate_value(self.vm.platform.validate_nic_types, value)
         self._nic_types = value
 
     @property
@@ -229,7 +231,8 @@ def serial_ports(self, value):
             value = int(value)
         except ValueError:
             raise InvalidInputError("serial_ports value must be an integer")
-        self.vm.platform.validate_serial_count(value)
+        non_negative_int(value, label="serial_ports")
+        self.ui.validate_value(self.vm.platform.validate_serial_count, value)
         self._serial_ports = value
 
     @property

COT/inject_config.py

@@ -3,7 +3,7 @@
 # inject_config.py - Implements "cot inject-config" command
 #
 # February 2014, Glenn F. Matthews
-# Copyright (c) 2014-2016 the COT project developers.
+# Copyright (c) 2014-2017 the COT project developers.
 # See the COPYRIGHT.txt file at the top-level directory of this distribution
 # and at https://github.com/glennmatthews/cot/blob/master/COPYRIGHT.txt.
 #
@@ -74,7 +74,7 @@ def config_file(self, value):
             if not self.vm.platform.CONFIG_TEXT_FILE:
                 raise InvalidInputError(
                     "Configuration file not supported for platform {0}"
-                    .format(self.vm.platform.__name__))
+                    .format(self.vm.platform))
         self._config_file = value
 
     @property
@@ -98,7 +98,7 @@ def secondary_config_file(self, value):
             if not self.vm.platform.SECONDARY_CONFIG_TEXT_FILE:
                 raise InvalidInputError(
                     "Secondary configuration file not supported "
-                    "for platform {0}".format(self.vm.platform.__name__))
+                    "for platform {0}".format(self.vm.platform))
         self._secondary_config_file = value
 
     @property

COT/ovf/ovf.py

@@ -365,7 +365,7 @@ def platform(self):
         if self._platform is None:
             self._platform = Platform.for_product_string(self.product_class)
             logger.info("OVF product class %s --> platform %s",
-                        self.product_class, self.platform.__name__)
+                        self.product_class, self.platform)
         return self._platform
 
     def validate_hardware(self):
@@ -803,9 +803,9 @@ def _info_string_header(self, width):
         str_list = []
         str_list.append('-' * width)
         str_list.append(self.input_file)
-        if self.platform and self.platform is not Platform:
+        if self.platform and self.platform.__class__ is not Platform:
             str_list.append("COT detected platform type: {0}"
-                            .format(self.platform.PLATFORM_NAME))
+                            .format(self.platform))
         str_list.append('-' * width)
         return '\n'.join(str_list)
 
@@ -1803,7 +1803,7 @@ def config_file_to_properties(self, file_path, user_configurable=None):
         i = 0
         if not self.platform.LITERAL_CLI_STRING:
             raise NotImplementedError("no known support for literal CLI on " +
-                                      self.platform.PLATFORM_NAME)
+                                      str(self.platform))
         with open(file_path, 'r') as f:
             for line in f:
                 line = line.strip()

COT/platforms/__init__.py

@@ -12,28 +12,29 @@
 
 """Package for identifying guest platforms and handling platform differences.
 
-The :class:`Platform` class describes the API
+The :class:`~COT.platforms.platform.Platform` class describes the API
 and provides a generic implementation that can be overridden by subclasses
 to provide platform-specific logic.
 
 In general, other modules should not access subclasses directly but should
-instead use the :meth:`Platform.for_product_string` API to
-derive the appropriate subclass object.
+instead use the :meth:`~COT.platforms.platform.Platform.for_product_string`
+API to derive the appropriate subclass object.
 
 API
 ---
 
 .. autosummary::
   :nosignatures:
 
-  Platform
+  ~COT.platforms.platform.Platform
 
 Platform modules
 ----------------
 
 .. autosummary::
   :toctree:
 
+  COT.platforms.platform
   COT.platforms.cisco_csr1000v
   COT.platforms.cisco_iosv
   COT.platforms.cisco_iosxrv