API Integration Patterns

Overview

APIs are the connective tissue of modern software. Whether you’re consuming a third-party service, building a public API for partners, or connecting your own microservices, the integration pattern you choose has lasting implications on performance, maintainability, and developer experience.

REST APIs

REST remains the most widely adopted pattern. Follow these conventions to build APIs that are predictable and easy to consume:

Resource Design

• Use plural nouns for collections: /users, /orders, /invoices.
• Nest related resources sparingly: /users/{id}/orders is fine, but avoid nesting deeper than two levels.
• Use HTTP methods semantically: GET (read), POST (create), PUT/PATCH (update), DELETE (remove).
• Return appropriate status codes: 200 (OK), 201 (Created), 204 (No Content), 400 (Bad Request), 401 (Unauthorized), 404 (Not Found), 422 (Validation Error), 500 (Server Error).

Pagination & Filtering

• Always paginate list endpoints. Cursor-based pagination (?after=abc123&limit=25) scales better than offset-based.
• Support common filters via query parameters: ?status=active&sort=-created_at.
• Include pagination metadata in the response: total, has_more, next_cursor.

Versioning

Version your API from day one. URL-based versioning (/v1/users) is the most explicit and widely understood. Header-based versioning is cleaner but harder to test in a browser.

GraphQL

GraphQL excels when clients need flexible queries across related data — particularly mobile apps that benefit from fetching exactly the fields they need in a single round trip.

When to Choose GraphQL

• Multiple client types (web, iOS, Android) with different data requirements.
• Complex data graphs with many relationships (e.g., social networks, project management tools).
• Rapidly evolving frontends that frequently need new field combinations.

Best Practices

• Use DataLoader to batch and cache database queries — the N+1 problem is GraphQL’s biggest performance trap.
• Implement query complexity analysis and depth limiting to prevent abusive queries.
• Prefer Relay-style pagination (connections with edges and cursors) for list fields.
• Use persisted queries in production to reduce payload size and prevent arbitrary query execution.

Webhooks

Webhooks flip the communication model: instead of polling an API, the service pushes events to your endpoint as they happen.

Implementing a Webhook Receiver

• Respond with 200 OK immediately, then process the payload asynchronously (queue it).
• Verify the signature header (HMAC-SHA256) to confirm the payload is authentic.
• Design for idempotency — you may receive the same event more than once.
• Store a unique event ID and skip duplicates.
• Implement retry logic on the sending side with exponential backoff.

Sending Webhooks

• Sign every payload with a shared secret using HMAC-SHA256.
• Retry delivery on 4xx/5xx responses with exponential backoff (e.g., 1s, 5s, 30s, 5m, 1h).
• Provide a webhook management UI where users can see delivery logs and manually retry.
• Send a minimal payload with an event type and resource ID — let the consumer fetch full details via API if needed.

Authentication & Security

• Use OAuth 2.0 with short-lived access tokens and refresh tokens for user-facing APIs.
• Use API keys for server-to-server communication, scoped to specific permissions.
• Always enforce HTTPS. Reject plain HTTP requests.
• Rate-limit all endpoints. Return 429 Too Many Requests with a Retry-After header.
• Log all API access for audit and debugging.

Need Help?

JAIK Solutions designs and builds APIs that scale. Whether you need a RESTful backend, a GraphQL gateway, or webhook infrastructure, reach out and we’ll architect the right solution.