Cant validate a list of values for duplicates using Python and Cerberus

Question

I am fairly new to Python and Cerberus. I have a requirement where I need to validate a list for any empty Strings or duplicates. Below is what I did:

import cerberus

myschema = {'uid': {'type': 'list', 'schema': {'type': 'string', 'required' : True}}}

cerberus.rules_set_registry.add('myschema', myschema)
newval = Validator(myschema)

test = {'uid' : {'10000', '10001', '10002', '10003', '10004', '10005'}}
newval.validate(test)

The output is always 'False' for some reason.
Alternatively, I tried the 'oneof' of-rules and came up with the below:

from cerberus import Validator
document = {'column_name' : ['BLAH', 'SEX', 'DOMAIN', 'DOMAIN']}

schema = {'column_name' : {'oneof' : [{'type': 'list', 'contains' : ['DOMAIN']}]} }
v = Validator(schema)
v.validate(document, schema)

The above always return True. I was hoping the 'oneof' can validate duplicates and the aforementioned is the right way. Can anyone here please correct me if I am wrong.!
Thanks in advance,
Nix

Answer 1

Alright.
I couldn't find an answer with Cerberus validator to check duplicates in a list.
I checked Json Schema where it is really easy. Below is the code:

from jsonschema import validate

schema = { "type": "array", "uniqueItems": True}

mylist  = ['1000', '1001', '1010', '1011', '1100', '1101', '1110', '1000']

# Returns None if validated; else a validation error
validate(instance = mylist, schema = schema)

In Cerberus, validation returns a True if validated right; else False. Whereas, Json Schema returns a None (in Python) if validated right else, throws a validation error as given below:

---------------------------------------------------------------------------
ValidationError                           Traceback (most recent call last)
<ipython-input-1-efa3c7f0da39> in <module>
      5 mylist  = ['1000', '1001', '1010', '1011', '1100', '1101', '1110', '1000']
      6 
----> 7 ans = validate(instance = mylist, schema = schema)
      8 if(ans == None): print('Validated as True')

~/Library/Python/3.8/lib/python/site-packages/jsonschema/validators.py in validate(instance, schema, cls, *args, **kwargs)
    932     error = exceptions.best_match(validator.iter_errors(instance))
    933     if error is not None:
--> 934         raise error
    935 
    936 

ValidationError: ['1000', '1001', '1010', '1011', '1100', '1101', '1110', '1000'] has non-unique elements

Failed validating 'uniqueItems' in schema:
    {'type': 'array', 'uniqueItems': True}

On instance:
    ['1000', '1001', '1010', '1011', '1100', '1101', '1110', '1000']