v3 simplifies validation

[spacether]

simplifes validation

• separate python classes are now written for OpenapiSchemas and their json schema type object and array output types
  • output classes are no longer generated for type: null/string/number/integer/bool
  • nested Schema_ class has been removed and its data is now in a non-nested schema class
  • it should be possible to implement this same pattern in statically typed languages
• __new__ method becomes the validate method
• no more use of generics when handling null/boolean/string/number/integer. Schema Classes use generics to set return types for object (dict) and array (tuple) types
• returned frozendict and tuple classes are now only instances of one class, instances no longer subclass all validated schemas
• frozendict changed to immutabledict to use generic type definitions in ouput class definitions
• all schema base classes and mixins deleted
• schema module refactored into submodules
• format helper methods as_date_/as_datetime/as_decimal_/as_uuid_ changed to functions in the schemas.format module, this allows string instances to be vanilla strings, which allows string literals to be returned when string enums are defined
• enums now stored by name in Schema.enums, this prevents collision with other json schema info
• server variables changed to DictSchema w/ validation
• request query/header/path/cookie/_params changed to DictSchema w/ validation
• response headers changed to DictSchema w/ validation
• json schema type object + array python output classes with names like SomeSchemaDict and SomeSchemaTuple will always run validation on inputs, even if instantiated directly like SomeSchemaDict(...), not from the schema validation method SomeSchema.validate(...)

Note

initially I defined Schema.output_type and output_types to define the output types that a schema generates
and I used that reference for property and __getitem__ return types, but pycharm did not see through to the type defined in output_type/output_types. It described the type as output_type
So instead I fully inspect each schema and write its output types for properties + __getitem__ return types

PR checklist

• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
• Run the following to build the project and update samples:

  ./mvnw clean package 
  ./bin/generate-samples.sh
  ./bin/utils/export_docs_generators.sh
  

  Commit all changed files.
  This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master.
  These must match the expectations made by your contribution.
  You may regenerate an individual generator by passing the relevant config(s) as an argument to the script, for example ./bin/generate-samples.sh bin/configs/python*.
  For Windows users, please run the script in Git BASH.