Add schema validation

[CunliangGeng]

Adding json schema to enable json data validation, which helps to ensure the integrity and quality of internal and external data.

JSON data validation libraries:

• Use jsonschema library to conduct data validation. It can directly validate json data against json schema.
• pydantic is also a very good data validation library, however it cannot validate json data against plain json schema and user must create models (python classes) from json schema to validate json data.

Resources:

• Understanding json schema
• JSON schema spec
• Implementations of JSON schema
  • JSON schema Generator from json data
  • Online json validator
    • https://json-schema.hyperjump.io/
    • https://jschon.dev/