Validation Error

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This error occurs when the request payload values do not conform to the data rules, types, or business constraints defined in the Domain Modeler.

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Error Response Example (RFC 9457)

{
  "type": "https://docs.apinow.app/errors/validation",
  "title": "Validation Error",
  "status": 422,
  "code": "VALIDATION_ERROR",
  "detail": "Field validation failed",
  "instance": "/api/v1/users",
  "errors": [
    {
      "detail": "Value 'invalid-email' is not a valid email address.",
      "pointer": "/email",
      "code": "validation"
    },
    {
      "detail": "Password must be at least 8 characters long.",
      "pointer": "/password",
      "code": "validation"
    }
  ]
}

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Troubleshooting Guide

For API Consumers (What it means & how to fix)

• Check Field Errors: Inspect the errors array in the response. Each item contains:
  • pointer: The JSON pointer pointing to the invalid property in your request payload (e.g., /email).
  • detail: A descriptive message of why the field failed validation.
• Payload Format: Ensure that data types are correct (e.g. sending a number instead of a string for numeric properties) and that required fields are not omitted.

For API Authors (Domain & API Modeler notes)

• Semantic Validators: The Serverless Engine automatically attaches validation rules based on applied Semantic Modules (like checking formatting for Email, Phone, URL, or constraints on Password and UserRole).
• Required Properties: Ensure that fields marked as “Required” in your Domain Modeler are actually necessary, or provide a default value to prevent validation failures.