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Step 5: Response Configuration ​

Response Configuration defines how your API responds to requests, including success responses, error handling, response headers, and data transformation.

Overview ​

The Response Configuration step allows you to:

  • Configure success and error response formats

  • Set up response headers and status codes

  • Transform and filter response data

  • Customize response metadata

Response Formats ​

Success Responses ​

Basic Success Response ​

json
{
  "success": true,
  "data": {
    "id": "sub_12345",
    "name": "John Doe",
    "email": "john@example.com",
    "rating": 5,
    "feedback": "Great product!",
    "submitted_at": "2024-01-15T10:30:00Z"
  },
  "message": "Feedback submitted successfully"
}

Minimal Success Response ​

json
{
  "success": true,
  "id": "sub_12345",
  "message": "Feedback submitted successfully"
}

Detailed Success Response ​

json
{
  "success": true,
  "data": {
    "id": "sub_12345",
    "name": "John Doe",
    "email": "john@example.com",
    "rating": 5,
    "feedback": "Great product!",
    "submitted_at": "2024-01-15T10:30:00Z",
    "processed_at": "2024-01-15T10:30:01Z",
    "status": "processed"
  },
  "metadata": {
    "version": "1.0",
    "request_id": "req_abc123",
    "processing_time": "150ms"
  },
  "message": "Feedback submitted successfully"
}

Error Responses ​

Validation Error Response ​

json
{
  "success": false,
  "error": {
    "code": "VALIDATION_ERROR",
    "message": "One or more fields failed validation",
    "details": [
      {
        "field": "email",
        "message": "Please enter a valid email address",
        "code": "INVALID_EMAIL"
      },
      {
        "field": "rating",
        "message": "Rating must be between 1 and 5",
        "code": "INVALID_RANGE"
      }
    ]
  },
  "request_id": "req_abc123"
}

Server Error Response ​

json
{
  "success": false,
  "error": {
    "code": "INTERNAL_SERVER_ERROR",
    "message": "An unexpected error occurred",
    "request_id": "req_abc123",
    "timestamp": "2024-01-15T10:30:00Z"
  }
}

Rate Limit Error Response ​

json
{
  "success": false,
  "error": {
    "code": "RATE_LIMIT_EXCEEDED",
    "message": "Too many requests. Please try again later.",
    "retry_after": 60,
    "limit": 100,
    "remaining": 0,
    "reset_time": "2024-01-15T11:00:00Z"
  }
}

HTTP Status Codes ​

Success Status Codes ​

200 OK ​

  • Standard successful response

  • Used for most successful operations

  • Includes response data

201 Created ​

  • Resource successfully created

  • Used for new submissions

  • Includes created resource data

202 Accepted ​

  • Request accepted for processing

  • Used for asynchronous operations

  • May not include final result

Error Status Codes ​

400 Bad Request ​

  • Invalid request format

  • Missing required fields

  • Malformed data

401 Unauthorized ​

  • Missing or invalid authentication

  • Expired tokens

  • Insufficient permissions

422 Unprocessable Entity ​

  • Validation errors

  • Business logic violations

  • Data format issues

429 Too Many Requests ​

  • Rate limit exceeded

  • Too many requests from same IP

  • API quota exceeded

500 Internal Server Error ​

  • Unexpected server errors

  • Database connection issues

  • System failures

Response Headers ​

Standard Headers ​

Content-Type ​

http
Content-Type: application/json; charset=utf-8

CORS Headers ​

http
Access-Control-Allow-Origin: https://your-frontend.com
Access-Control-Allow-Methods: GET, POST, PUT, DELETE, OPTIONS
Access-Control-Allow-Headers: Content-Type, Authorization
Access-Control-Allow-Credentials: true

Cache Control ​

http
Cache-Control: no-cache, no-store, must-revalidate
Pragma: no-cache
Expires: 0

Custom Headers ​

API Version ​

http
X-API-Version: 1.0
X-API-Deprecated: false

Request Tracking ​

http
X-Request-ID: req_abc123
X-Response-Time: 150ms
X-Processing-Time: 120ms

Rate Limiting ​

http
X-RateLimit-Limit: 100
X-RateLimit-Remaining: 95
X-RateLimit-Reset: 1642248000

Data Transformation ​

Output Formatting ​

Date Formatting ​

javascript
// Input: "2024-01-15T10:30:00Z"
// Output: "2024-01-15 10:30:00"
{
  "field": "submitted_at",
  "format": "YYYY-MM-DD HH:mm:ss"
}

// Input: "2024-01-15T10:30:00Z"
// Output: "January 15, 2024"
{
  "field": "submitted_at",
  "format": "MMMM DD, YYYY"
}

Number Formatting ​

javascript
// Input: 1234.56
// Output: "1,234.56"
{
  "field": "price",
  "format": "currency",
  "currency": "USD"
}

// Input: 1234.56
// Output: "1,234.56"
{
  "field": "rating",
  "format": "decimal",
  "decimalPlaces": 2
}

Text Processing ​

javascript
// Input: "  John Doe  "
// Output: "John Doe"
{
  "field": "name",
  "format": "trim"
}

// Input: "john@example.com"
// Output: "j***@example.com"
{
  "field": "email",
  "format": "mask",
  "maskChar": "*",
  "visibleChars": 1
}

Field Filtering ​

Include/Exclude Fields ​

javascript
// Include only specific fields
{
  "include": ["id", "name", "email", "submitted_at"]
}

// Exclude sensitive fields
{
  "exclude": ["password", "ssn", "credit_card"]
}

// Conditional inclusion
{
  "conditional": {
    "include": ["admin_notes"],
    "condition": {
      "field": "user_role",
      "operator": "equals",
      "value": "admin"
    }
  }
}

Nested Field Filtering ​

javascript
// Filter nested objects
{
  "include": {
    "user": ["id", "name", "email"],
    "metadata": ["created_at", "updated_at"]
  }
}

Computed Fields ​

Calculated Fields ​

javascript
// Add computed field
{
  "computed": {
    "field": "days_since_submission",
    "formula": "current_date - submitted_at",
    "type": "number"
  }
}

// Add status field
{
  "computed": {
    "field": "status",
    "formula": "rating >= 4 ? 'positive' : 'negative'",
    "type": "string"
  }
}

Aggregated Fields ​

javascript
// Add count field
{
  "computed": {
    "field": "total_submissions",
    "formula": "count(*)",
    "type": "number"
  }
}

// Add average field
{
  "computed": {
    "field": "average_rating",
    "formula": "avg(rating)",
    "type": "number",
    "decimalPlaces": 2
  }
}

Response Templates ​

Template Variables ​

System Variables ​

javascript
{
  "variables": {
    "timestamp": "{{current_timestamp}}",
    "request_id": "{{request_id}}",
    "api_version": "{{api_version}}",
    "processing_time": "{{processing_time}}"
  }
}

Field Variables ​

javascript
{
  "variables": {
    "user_name": "{{name}}",
    "user_email": "{{email}}",
    "submission_id": "{{id}}",
    "submission_date": "{{submitted_at}}"
  }
}

Template Examples ​

Email Confirmation Template ​

json
{
  "success": true,
  "data": {
    "id": "{{id}}",
    "name": "{{name}}",
    "email": "{{email}}",
    "submitted_at": "{{submitted_at}}"
  },
  "message": "Thank you {{name}}! Your feedback has been submitted successfully.",
  "confirmation": {
    "email_sent": true,
    "email_address": "{{email}}",
    "confirmation_id": "{{confirmation_id}}"
  }
}

Admin Notification Template ​

json
{
  "success": true,
  "data": {
    "id": "{{id}}",
    "name": "{{name}}",
    "email": "{{email}}",
    "rating": "{{rating}}",
    "feedback": "{{feedback}}",
    "submitted_at": "{{submitted_at}}"
  },
  "admin_notification": {
    "sent": true,
    "recipients": ["admin@company.com"],
    "priority": "{{rating >= 4 ? 'low' : 'high'}}"
  }
}

Error Handling ​

Error Response Configuration ​

Error Message Templates ​

javascript
{
  "error_templates": {
    "validation_error": "Please check the following fields: {{error_fields}}",
    "server_error": "We're experiencing technical difficulties. Please try again later.",
    "rate_limit_error": "Too many requests. Please wait {{retry_after}} seconds before trying again."
  }
}

Error Logging ​

javascript
{
  "error_logging": {
    "enabled": true,
    "level": "error",
    "include_request_data": true,
    "include_user_data": false,
    "external_service": "sentry"
  }
}

Error Recovery ​

Retry Logic ​

javascript
{
  "retry_config": {
    "max_retries": 3,
    "retry_delay": 1000,
    "backoff_multiplier": 2,
    "retryable_errors": ["timeout", "connection_error"]
  }
}

Fallback Responses ​

javascript
{
  "fallback": {
    "enabled": true,
    "response": {
      "success": false,
      "error": {
        "code": "SERVICE_UNAVAILABLE",
        "message": "Service temporarily unavailable. Please try again later."
      }
    }
  }
}

Performance Optimization ​

Response Caching ​

Cache Configuration ​

javascript
{
  "caching": {
    "enabled": true,
    "ttl": 300,
    "cache_key": "{{endpoint_id}}_{{user_id}}",
    "invalidate_on": ["update", "delete"]
  }
}

Cache Headers ​

http
Cache-Control: public, max-age=300
ETag: "abc123"
Last-Modified: Wed, 15 Jan 2024 10:30:00 GMT

Response Compression ​

Compression Settings ​

javascript
{
  "compression": {
    "enabled": true,
    "algorithm": "gzip",
    "min_size": 1024,
    "content_types": ["application/json", "text/html"]
  }
}

Testing Response Configuration ​

Test Cases ​

Success Response Test ​

bash
curl -X POST https://your-api.com/endpoint/user-feedback \
  -H "Content-Type: application/json" \
  -d '{
    "name": "John Doe",
    "email": "john@example.com",
    "rating": 5,
    "feedback": "Great product!"
  }'

Error Response Test ​

bash
curl -X POST https://your-api.com/endpoint/user-feedback \
  -H "Content-Type: application/json" \
  -d '{
    "name": "",
    "email": "invalid-email",
    "rating": 6
  }'

Response Validation ​

Schema Validation ​

javascript
{
  "response_schema": {
    "type": "object",
    "required": ["success", "data"],
    "properties": {
      "success": { "type": "boolean" },
      "data": { "type": "object" },
      "message": { "type": "string" },
      "metadata": { "type": "object" }
    }
  }
}

Next Steps ​

After configuring response settings:

  1. Test and Deploy → Step 6: Testing & Deployment