Webhook
A webhook is an HTTP callback mechanism that sends event-related information to a configured endpoint when a specified event occurs.
The Design of Web APIs, Second Edition
A webhook call is an HTTP request sent automatically to notify a consumer when an event occurs.
- How it is used
- Notifies consumers about provider-generated events in real time and avoids inefficient polling.
- How deep it goes
- Defines webhook rationale, alternatives, event design, security, acknowledgment, failure recovery, and OpenAPI description.
- Examples
- Uses banking transaction notifications, consumer-defined URLs, POST events, retry limits, notification history, and OpenAPI webhook definitions.
- What you can do after
- Build it from scratch by designing, securing, documenting, acknowledging, and recovering consumer-implemented webhook operations.
Read how The Design of Web APIs, Second Edition explains webhook →
Contract Testing in Action
A webhook is an HTTP callback that delivers an event notification from one system to another when a specified event occurs.
- How it is used
- Triggers provider verification automatically when a consumer publishes a changed contract across separate CI/CD pipelines.
- How deep it goes
- Walks through token storage, event selection, request payloads, provider configuration, and mismatch testing; defers other webhook event types.
- Examples
- Uses WebConsumer, MoviesAPI, GitHub repository dispatches, and a 200-to-201 response-status mismatch.
- What you can do after
- Operate/configure Pact webhooks to dispatch provider verification and surface changed-contract mismatches in CI/CD.
Effective Platform Engineering
A webhook is an HTTP callback mechanism that delivers event notifications from one system to another when specified events occur.
- How it is used
- Uses event notifications to trigger platform upgrades, deployment workflows, and automated conformance testing.
- How deep it goes
- Explains webhook publication, subscription, and operational benefits, but stops short of protocol-level implementation details.
- Examples
- Uses repository pushes, tags, cluster upgrades, CI tests, deployment workflows, logs, and Jira tickets as concrete event artifacts.
- What you can do after
- Operate/configure subscribers that trigger upgrades, tests, and issue updates from platform events.
Platform Engineering on Kubernetes
A webhook is an HTTP callback that allows one system to notify another system when an event occurs.
- How it is used
- Triggers service and environment pipelines when Git repositories report source or configuration changes.
- How deep it goes
- Explains webhook registration and pipeline triggering, while stopping short of protocol-level implementation details.
- Examples
- Uses merged source changes and environment-configuration changes as webhook-triggered pipeline events.
- What you can do after
- Operate/configure pipelines that react to repository changes while retaining polling as a synchronization fallback.
Read how Platform Engineering on Kubernetes explains webhook →
Secure APIs
A webhook is an HTTP callback that delivers event notifications to a user-specified URL.
- How it is used
- Uses user-configured callbacks to trigger automated responses to payment and other API events.
- How deep it goes
- Traces webhook operation through SSRF abuse, internal-service discovery, and resulting attack preparation.
- Examples
- Illustrates payment notifications, local-network scanning, PostgreSQL discovery, and Jenkins compromise.
- What you can do after
- Evaluate webhook configurations for their potential to trigger requests to internal and external services.
Effective Conversational AI
A webhook is an API endpoint that is invoked automatically when a specified event occurs in another system.
- How it is used
- Uses event-triggered API calls in a chatbot’s orchestration layer to access external systems or handle conversational tasks.
- How deep it goes
- Defines pre- and post-processing events and illustrates transcript updates with pseudocode, while deferring platform-specific terminology and formats.
- Examples
- Shows a post-webhook appending user messages and bot replies as labeled lines in a transcript.
- What you can do after
- Apply a post-webhook to update a transcript with available user messages and bot replies.
Related concepts
- contractkind of · An API contract is a specification of the operations, data, and behavioral expectations that govern interactions between software components.
- business problemaddresses · A business problem is an organizational need, objective, constraint, or challenge that a proposed solution is intended to address.
- Pact Broker CLIproduced by · A command-line interface for publishing and managing Pact contracts and interacting with a Pact Broker.
- triggerkind of · A trigger is an event, condition, input, or schedule that causes or signals an action, process, or state transition to begin or proceed.
- pollingaddresses · Polling is the repeated checking or querying of a resource, system, or condition, often at intervals, to detect data, events, or state changes.
- JSONuses · JSON is a standardized, language-independent text format for representing structured data using objects, arrays, strings, numbers, Boolean values, and null.
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