Contract-First API Design

API Gateway Proxy
Schema Validation

Validate API requests and responses against JSON Schema and OpenAPI specifications. Catch errors early with detailed validation reporting.

View Examples Compare Standards
"type" : "object"
"required" : ["name", "email"]
"properties" : {...}
"additionalProps" : false

Schema Validation Standards

Choose the right schema standard for your API gateway

📄
JSON Schema
IETF standard for JSON document validation with rich type system.
  • Type checking (string, number, array)
  • Required field validation
  • Pattern matching with regex
  • Nested object support
  • Custom error messages
📜
OpenAPI 3.0/3.1
Full API specification with request/response validation.
  • Endpoint definitions
  • HTTP method validation
  • Parameter constraints
  • Response schema enforcement
  • Security scheme support
📚
AsyncAPI
Event-driven API schema validation for streaming.
  • WebSocket message validation
  • Kafka event schemas
  • Channel definitions
  • Publish/subscribe patterns
  • Real-time streaming

Schema Examples

Common validation patterns for API gateway proxies

📄 JSON Schema for User Draft-07 
{
  "$schema": "https://json-schema.org/draft-07/schema",
  "$id": "https://api.example.com/schemas/user",
  "type": "object",
  "required": ["name", "email"],
  "properties": {
    "name": {
      "type": "string",
      "minLength": 1,
      "maxLength": 100
    },
    "email": {
      "type": "string",
      "format": "email"
    },
    "age": {
      "type": "integer",
      "minimum": 0,
      "maximum": 150
    }
  },
  "additionalProperties": false
}
📜 OpenAPI 3.0 Endpoint OAS3
"paths": { "/v1/chat/completions": { "post": { "requestBody": { "required": true, "content": { "application/json": { "schema": { "type": "object", "required": ["model", "messages"], "properties": { "model": { "type": "string", "enum": ["gpt-4", "gpt-3.5-turbo"] }, "messages": { "type": "array", "items": { "$ref": "#/components/schemas/Message" } } } } } } } } } } }

Feature Comparison

Choose the right validation approach for your needs

Feature JSON Schema OpenAPI AsyncAPI
Type Validation ✓ ✓ ✓
Required Fields ✓ ✓ ✓
HTTP Method Routing ✗ ✓ ✗
Response Validation ◐ ✓ ✓
Streaming Support ✗ ◐ ✓
Security Schemes ✗ ✓ ✓
Documentation Gen ✗ ✓ ✓