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

Try Optic • Document APIs • Detect Changes • Optic GitBot • Contributing License

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Try Optic

Similar to git init

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 optic.yml

ie npm start -> api start

ie 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
    usesTask: 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

Similar to git add

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

Detect API Changes

Similar to git status

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 api status:

Learn more about detecting + reviewing API Diffs

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.

🚦 Prevent Breaking Changes

Discover breaking changes before they're merged. Request compatible changes in code review, or coordinate the breaking changes with consumers.

🔎 API First

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.

✅ Updated Docs

No more doc drift. When you approve an API change Optic also updates the specification.

Install & Set up the GitBot

Documentation https://useoptic.com/docs

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.

Resources

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
Join Community
Book Maintainer Office Hours

Want to help us design the next features? Book Maintainer Office Hours

License

MIT

Contributors ✨

Thanks goes to these wonderful people (emoji key):

_{Aidan Cunniffe} 📖 💻	_devdoshi 📖 💻	_{Evan Mallory} 📖	_{Jaap van Hardeveld} 💻 📖	_{Ronak Shah} 💻 📖	_taraedits 📖	_{Lou Manglass} 💻 📖
_{Nate Meyer} 💻	_{Tim Gates} 📖	_{Matthew Hudson} 📖	_LaV 📖	_{Gaurav Nelson} 📖	_{Ross Nordstrom} 🎨 💻 🐛	_{Kin Lane} 🤔 🖋
_{Viljami Kuosmanen} 🤔 🖋	_{Richard Crowley} 🔬 🤔	_dnmtr 👀	_{Tim Perry} 💻	_jordaniza 📖	_{Sandy Vanderbleek} 📖	_{Dave Rolsky} 📖
_{Baptiste Darthenay} 📖	_{Alex Miller} 📖	_{Joseph Shearer} 💻	_{Ray Bejjani} 📖	_{Adrien Brault} 📖	_{Nicholas Lim} 📖 💻	_{Stephen Mizell} 💻