Implementing Request Validation

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "required": ["email", "age"],
  "properties": {
    "email": { "type": "string", "format": "email" },
    "age":   { "type": "integer", "minimum": 0, "maximum": 150 }
  },
  "additionalProperties": false
}

parameters:
  - name: page
    in: query
    schema: { type: integer, minimum: 1, maximum: 1000, default: 1 }
  - name: sort
    in: query
    schema: { type: string, enum: [asc, desc] }

local body, err = kong.request.get_body()
if not body or not body.amount or body.amount <= 0 then
  return kong.response.exit(400, {
    error = "amount must be positive",
    code = "INVALID_AMOUNT"
  })
end

{
  "type": "https://api.example.com/errors/validation",
  "title": "Validation Failed",
  "status": 400,
  "detail": "Request body failed schema validation",
  "instance": "/v1/users",
  "errors": [
    { "field": "email", "code": "invalid_format" },
    { "field": "age",   "code": "out_of_range" }
  ]
}