Understanding the difference between webhooks and APIs can be challenging for many beginners in the tech world. Even experts sometimes struggle with these concepts, especially in platforms where precision is essential. Let’s break down these two fundamental technologies, provide practical insights into their usage, and discuss how integration platforms handle both.
Basic Definitions
At its core, an API (Application Programming Interface) is a mechanism that enables communication between different software components. An API typically receives an HTTPS event (a message), processes it, and sends back a response. The API provider defines the interface, while the client (caller of the API) must conform to it.
On the other hand, a webhook is a mechanism for receiving real-time notifications from different systems. It originates an HTTPS API call to a pre-configured endpoint, often triggered by an event in the originating system. In this case, the webhook defines the interface and expects the recipient system (commonly referred to as the “Webhook Handler”) to conform to its structure.
The key difference is that APIs are about requests and responses initiated by a client, whereas webhooks are about event-driven notifications undertaken by a server.
Support for APIs and Webhooks in Applications
Most modern applications support both APIs and webhooks to facilitate integration with other systems. However, many legacy applications, or those only partially modernized, often lack webhook capabilities. In such cases, alternative protocols like polling or messaging queues may be used, but they are generally more complex and/or less efficient.
From an enterprise perspective, webhooks offer an elegant way to receive real-time updates from various systems. Despite this, the adoption of webhooks across enterprise applications varies. I believe webhooks should be the default standard for receiving outbound events due to their simplicity and real-time nature.
Support for APIs and Webhooks in Integration Platforms
Enterprise integration platforms serve as intermediaries between applications, often acting as both API providers and consumers. To meet the needs of modern integrations, these platforms must support three key patterns:
- Exposing New APIs: These are APIs designed by the provider for general use, often tailored to the platform’s specific capabilities.
- Exposing APIs to Act as Webhook Handlers: The API conforms to inbound requests originating from Webhook event messages.
- API Invocation: The integration platform acts as the client, invoking APIs on other systems.
While these patterns may seem similar, they require different approaches, especially when dealing with specifications like OpenAPI.
- Use Case 1: The platform defines the API spec, giving it complete control over the design.
- Use Case 2: The platform interprets webhook definitions provided by external systems.
- Use Case 3: The platform consumes API definitions from external systems, relying on their accuracy and completeness.
Building for APIs and Webhooks
A robust integration platform must support all three use cases and provide tools and workflows that make these processes intuitive. For example:
- When registering APIs, the platform should allow users to design new APIs, generate them from underlying services, or derive them from serverless function interfaces.
- For webhooks, it should support importing event examples or performing live test calls to capture webhook structures. It’s silly to write an API spec to represent the webhook handler.
The ability to handle these use cases seamlessly sets apart a strong integration platform from a basic one.
The Future of Integration with PolyAPI
At PolyAPI, we are committed to redefining the developer experience for building and operating integrations, orchestrations, and microservices. Whether creating APIs, interpreting webhook events, or managing complex enterprise integrations, our platform provides a unified approach to simplify these workflows.
If this vision resonates with you, or if you’re curious about how we’re transforming enterprise integration, reach us at hello@polyapi.io. Together, we can shape the future of integration technology.