[Bug]: Exception in CLI if `replicas` in `.dstack.yml` is invalid

[jvstme]

Steps to reproduce

1. Create a service configuration with replicas set to a range without upper bound

   > cat drope.yml 
   type: service
   
   commands:
     - pip install drope
     - drope
   port: 8000
   
   replicas: 2..
   

2. Try running the service

   dstack run . -f drope.yml
   

Expected behaviour

dstack CLI displays an error message

The maximum number of replicas must be set

Actual behaviour

dstack CLI fails with unhandled exception

Traceback (most recent call last):
  File "/home/jvstme/git/dstack/dstack/venv/bin/dstack", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/home/jvstme/git/dstack/dstack/src/dstack/_internal/cli/main.py", line 67, in main
    args.func(args)
  File "/home/jvstme/git/dstack/dstack/src/dstack/_internal/cli/commands/run.py", line 102, in _command
    configuration_path, conf = load_configuration(
                               ^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/src/dstack/api/utils.py", line 68, in load_configuration
    conf = parse_configuration(yaml.safe_load(f))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/src/dstack/_internal/core/models/configurations.py", line 287, in parse
    conf = RunConfiguration.parse_obj(data).__root__
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/main.py", line 526, in parse_obj
    return cls(**obj)
           ^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/main.py", line 339, in __init__
    values, fields_set, validation_error = validate_model(__pydantic_self__.__class__, data)
                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/main.py", line 1074, in validate_model
    v_, errors_ = field.validate(value, values, loc=field.alias, cls=cls_)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/fields.py", line 881, in validate
    v, errors = self._validate_singleton(v, values, loc, cls)
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/fields.py", line 1058, in _validate_singleton
    return self._validate_discriminated_union(v, values, loc, cls)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/fields.py", line 1147, in _validate_discriminated_union
    return sub_field.validate(v, values, loc=(*loc, display_as_type(sub_field.type_)), cls=cls)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/fields.py", line 881, in validate
    v, errors = self._validate_singleton(v, values, loc, cls)
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/fields.py", line 1098, in _validate_singleton
    return self._apply_validators(v, values, loc, cls, self.validators)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/fields.py", line 1154, in _apply_validators
    v = validator(cls, v, values, self, self.model_config)
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/class_validators.py", line 337, in <lambda>
    return lambda cls, v, values, field, config: validator(v)
                                                 ^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/main.py", line 711, in validate
    return cls(**value)
           ^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/main.py", line 339, in __init__
    values, fields_set, validation_error = validate_model(__pydantic_self__.__class__, data)
                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/venv/lib64/python3.12/site-packages/pydantic/main.py", line 1100, in validate_model
    values = validator(cls_, values)
             ^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/jvstme/git/dstack/dstack/src/dstack/_internal/core/models/configurations.py", line 265, in validate_scaling
    if replicas.min != replicas.max and not scaling:
       ^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'min'

dstack version

0.17.0rc2

Server logs

No response

Additional information

No response

[peterschmidt85]

This issue is stale because it has been open for 30 days with no activity.

[peterschmidt85]

This issue was closed because it has been inactive for 14 days since being marked as stale.

[jvstme]

Still relevant

[peterschmidt85]

This issue is stale because it has been open for 30 days with no activity.

[peterschmidt85]

This issue was closed because it has been inactive for 14 days since being marked as stale. Please reopen the issue if it is still relevant.