Implementing webhooks: Benefits and best practices

Benefits of webhooks

Webhooks facilitate communication between systems -- like notifying an IT department of a new work ticket or an insurance company of a new claim -- but they also offer the following benefits:

• Fast and easy setup. The process for configuring webhooks can vary depending on the desired level of customization. Some vendors offer integration with a list of third-party apps and can provide auditing, scalability and security features, making predefined webhooks enterprise-ready.
• Real-time updates. Instead of periodically querying another system for updates that could create delays in data transfer, webhooks work directly between existing endpoints, automatically sending an API call once a qualifying event occurs. These notifications can then trigger additional actions in a workflow.
• Efficient resource usage. Frequent update requests can expend unnecessary resources, but webhooks are configured to push notifications only in response to specific events. API calls are sent over HTTP/ HTTPS below the UI and generally require less processing power than polling.

Webhooks can be an effective systems integration and automation tool when used appropriately. While it is possible to create an additional endpoint in the middle to transform or redirect webhook requests, introducing an intermediary layer could increase latency, add complexity and prompt additional security considerations. APIs might be a more appropriate communication mechanism for those looking for more control over the sending, processing and securing of data.

Webhooks best practices

Webhooks can accommodate a range of implementation scenarios. Here's a quick breakdown of some overarching best practices to consider when moving from concept to design and deployment.

Build a system for people

The best way to get started with webhooks is to have a specific use case. A webhook implementation strategy should aim to optimize performance and improve processes, not inhibit them. Be sure to ask: What kind of logical actions should certain events trigger? What is the effect on an established workflow?

For example, a webhook could create a work ticket to prompt code review or notify a team using an instant messenger system. Depending on the volume of events, a series of instant messages could overwhelm the team and cause disruption. Webhook implementations that make sense on paper might not look the same upon execution. As a result, consider how both the notification method and delivery cadence best support the teams that work with them.

Test the webhooks

A sprinter wouldn't run a race without first warming up -- unless they want to pull a hamstring. Webhook testing is like a warm-up. It can confirm that a webhook performs as designed or allows a team to catch and address issues before they proliferate. Different tests can target specific implementation focus areas or concerns, such as load tests for scalability or functional tests to see how a system recovers from errors.

Plan for failures and retries

Even the best systems experience downtime. Network failures or server issues can cause webhook failure, meaning important or time-sensitive information could get lost or overlooked due to webhooks' fire-and-forget approach. While many platforms already implement an automatic retry mechanism to perform a certain number of delivery attempts, proactively integrating error-handling capabilities like retry logic and exponential backoff into the webhook process is essential for maintaining system reliability and resiliency.

Log and monitor webhook activity

Automatic retries are not a fail-safe recovery strategy. If, for example, a webhook fails due to incorrect payload formatting, a retry is unlikely to resolve the issue. Instead, a comprehensive logging and monitoring system can help teams identify an issue for troubleshooting.

If an error isn't logged or is somehow missed, consider designing a self-healing process instead of adding another audit to the workflow to minimize the need for manual intervention.

Avoid batch processing

Webhooks are lightweight mechanisms designed to push data in a single direction, from one location to another, as qualifying events occur. Batch processing creates large payloads that can cause delays, effectively eliminating a webhook's real-time benefits. Pushing file size limits might also require a developer to split batches, leading to extra code, out-of-order transactions and possible failures.

Prioritize webhook security

Webhook endpoints are typically exposed to the internet, making them attractive targets for attack and exploitation. Consequently, various methods exist for securing webhooks to protect data in transit. Both the sending and receiving systems need to support the same form of authentication.

As a first step, threat modeling can help organizations identify potential vulnerabilities and security risks to better invest in appropriate countermeasures, like encryption or mutual authentication. Many systems that support webhooks also support basic authentication, secrets management or hash-based message authentication code (HMAC) for identity verification.

Matt Heusser is managing director at Excelon Development, where he recruits, trains and conducts software testing and development.