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Principles of Awesome APIs and How to Build Them.
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Keavy McMinn
November 18, 2019
Programming
17k
128
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Principles of Awesome APIs and How to Build Them.
Keavy McMinn
November 18, 2019
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Transcript
Principles of Awesome APIs and How to Build Them. Keavy
McMinn, Fastly RubyConf 2019 @keavy
None
None
None
Try to work with the wind, don't fight it all
the time.
Consistent. Stable. Well-documented.
APIs: Our experience as consumers
APIs: Our experience as producers
APIs: Our experience as producers Fixing it would actually break
it.
APIs: Our experience as producers
Application Programming Interface
None
APIs = Constraints
Work with the constraints.
Remember these constraints are good for us too.
None
None
None
Consistent
Consistent Consistent data
✅ { "admin": true } ❌ { "admin": "1" }
API Descriptions — JSON Schema — Open API (formerly Swagger)
— RAML — APIs.json — API Blueprint — Postman Collections — Async API
Consistent Have one source of truth.
Have one source of truth. JSON Schema
JSON Schema committee gem https://github.com/interagent/committee
JSON Schema PRMD gem https://github.com/interagent/prmd
JSON Schema Online examples http://bit.ly/heroku-schema
It will be amaaazing!
Consistent Monitor your inconsistencies.
Monitor your inconsistencies. Compare what you say and what you
do.
Monitor your inconsistencies. Try a portion of your API
Monitor your inconsistencies. Technical deep dive
Monitor your inconsistencies. Technical deep dive https://github.com/whitequark/parser
# Get a dog. get "/dogs/:dog_id" do authorize_access :users, :bots
# finds the dog # renders the dog as JSON end
Then it will be amaaazing!
Stable
Stable Invest in upfront design.
Invest in upfront design. — What will users do with
it? — What does your business need from it? — What does it look like? — What will you call it?
Remember: puppies APIs are for life not just for Christmas!
https://www.flickr.com/photos/27587002@N07/5170590074
Design while the cost of change is low.
Stable A calm space.
metoffice.gov.uk
Stable
Change itself is not necessarily bad. Negative impact from change
is bad.
Minimize the negative impact
Well-documented
Well-documented Inform users about everything, early and often
Well-documented Then remember that people don’t read.
Well-documented Enable a holistic view. — Endpoints that are undocumented
— Endpoints that are in any special phase — Anything to be deprecated — Dates
Well-documented Governance
Well-documented Shared understanding is easier when it’s all written down.
Well-documented Internal guides
Well-documented API Styleguide
API Styleguide Avoid verbs and adjectives ❌ GET /pets/most-recent ✅
GET /pets?sort=date-added
API Styleguide Make exceptions deliberately GET /repos/:owner/:repo/releases/latest
Well-documented Internal guides
Well-documented Who is responsible for what?
Well-documented Who gets a say in decision making?
It doesn’t have to be fucking hard. It just has
to be consistent. Which is fucking hard. — Brett Sutton, Triathlon coach
Good luck! Thank you, @keavy