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Optic uses real traffic to document and test your APIs
- Language agnostic, works with any Rest API
- Optic observes development traffic and learns your API's behavior
- Optic detects API changes by diffing traffic against the current specification
- Optic adds an accurate API changelog to every Pull Request
Install Optic with npm or yarn"
yarn global add @useoptic/cli npm install @useoptic/cli -g
Then run init command:
## Navigate to your API project directory api init
Set up aliases for the commands your team runs when building the API in
npm start ->
newman run mycollection.json ->
api run postman-tests
name: My API tasks: start: command: npm start inboundUrl: http://localhost:4000 postman-tests: command: newman run mycollection.json useTask: start
How does Optic monitor local traffic? Whenever you start your API or run tests using Optic's CLI, it will observe your traffic and surface API diffs. All of this processing is done locally, in the background, by a Rust binary built from the open source code in this repository.
Document your API using real traffic
Once you add Optic to your API, hit it with some traffic, and document your first endpoints.
You just have to provide Optic with your API paths, and it will document every status code, response body, and request body automatically based on its observations.
You don't have to worry about hitting every possible request/response your first go -- Optic isn't "one-shot", it builds your spec up incrementally as it makes more observations about your API's behavior. For example, if Optic sees a
200 for an endpoint, and later sees a
400 for the same endpoint, it will help you add the new response.
api start [optic] Starting My API API on Port: 3005, with npm run server-start
- Document your API with Optic
- Video: Quinn Slack from Sourcegraph documenting GitHub's API in 10 minutes
Detect API Changes
While you develop your API and run tests locally, Optic diffs the traffic to find new endpoints, or changes to existing endpoints. These API diffs are listed when you run
Use the Optic UI to Review Diffs + Update your Specification
Similar to staging changes
When Optic detects an API diff, it helps you:
- Document new endpoints without writing a bunch of OpenAPI
- Update your API specification with a few clicks
- Detect any unplanned changes, breaks and regressions, then fix them
An API Changelog in Every PR
Similar to GitHub's compare page, but for API changes
The Optic GitBot adds an API Changelog during Code Review, so your team understands how the API will change when each PR is merged.
Discover breaking changes before they're merged. Request compatible changes in code review, or coordinate the breaking changes with consumers.
Adding explicit API changelogs in PRs facilitates discussion and leads to better API design. It's also a great way to make sure unintended API changes don't get deployed.
No more doc drift. When you approve an API change Optic also updates the specification.
- Read the full docs at: useoptic.com/docs.
- Want to contribute? Check out the Contribution Guidelines.
- To get set up working on the project, please review our Developer Setup guide as well.
Read our about Aidan + Dev's vision for the space Read: Git for APIs
Listen to Optic on Software Engineering Daily
Read API Evangelist on Optic Automatically Generate OpenAPI For Your APIs Just By Using Them
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Thanks goes to these wonderful people (emoji key):
This project follows the all-contributors specification. Contributions of any kind welcome!