Support for custom tags?

[yamokosk]

I apologize if I missed this in the docs for kwalify or pykwalify, or if this was already addressed in an earlier issue (I have searched but cannot find anything). I'd like to validate a schema that uses custom tags. Between the pyyaml and pykwalify documentation this is the best I was able to come up with. But its obviously not right. Example:

import yaml
from pykwalify.core import Core 

class MyTag(yaml.YAMLObject):
    yaml_tag = u'!MyTag'
    def __init__(self, name, parameter):
        self.name = name
        self.parameter = parameter

    def __repr__(self):
        return "%s(name=%r, parameter=%r)" % (
            self.__class__.__name__, self.name, self.parameter)

data = yaml.load("""
!MyTag
name: "aname"
parameter: 2
""")

print("dump: {}".format(yaml.dump(data)))

schema = yaml.load("""
type: !!python/object:__main__.MyTag
  type: map
  mapping:
    name:
      type: str
    parameter:
      type: int
""")

c = Core(source_data=data, schema_data=schema)
c.validate(raise_exception=True)

Output:

dump: !MyTag {name: aname, parameter: 2}

Traceback (most recent call last):
  File "example.py", line 34, in <module>
    c.validate(raise_exception=True)
  File "/usr/local/lib/python2.7/dist-packages/pykwalify/core.py", line 155, in validate
    self._start_validate(self.source)
  File "/usr/local/lib/python2.7/dist-packages/pykwalify/core.py", line 197, in _start_validate
    root_rule = Rule(schema=self.schema)
  File "/usr/local/lib/python2.7/dist-packages/pykwalify/rule.py", line 66, in __init__
    self.init(schema, "")
  File "/usr/local/lib/python2.7/dist-packages/pykwalify/rule.py", line 399, in init
    path=path,
pykwalify.errors.RuleError: <RuleError: error code 4: Key 'type' in schema rule is not a string type (found MyTag): Path: '/'>

[Grokzen]

Custom tags is not supported natively and i do not have any immediate plans for supporting them right now.

[Grokzen]

@yamokosk Can you supply a working script that correctly loads the custom tag you made and where it would build up a data object that acctually work on the python side so i can then implement this in the code base?

[Grokzen]

@yamokosk So i was thinking, in theory you should be able to add in any tag by modifying the following variable https://github.com/Grokzen/pykwalify/blob/master/pykwalify/compat.py#L10 that is the ruamel.yaml object and you should be able to add in any tags you want same way as here https://github.com/Grokzen/pykwalify/blob/master/pykwalify/core.py#L68 and if you do this before you construct your Core object it should be added to your parser when loading your schema/data files. It might be some issues with the ordering of imports and adding the tag, but it should be possible to make that work i guess.