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Fern Definitionapi.yml reference

The api.yml configuration file

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Availability in Fern Definition

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Environments

Fern Definition isn’t recommended for new customers and Fern isn’t accepting feature requests for this format. It remains supported for existing users.

A fern/ folder has a special file called api.yml, which includes all the API-wide configuration.

$fern/
$├─ fern.config.json
$├─ generators.yml
$└─ definition/
$ ├─ api.yml
$ ├─ pet.yml
$ ├─ store.yml
$ └─ user.yml

API name

This name is used to uniquely identify your API in your organization. If you just have one API, then api is a sufficient name.

api.yml
1name: api

API description

You can define a top level API description. This description will come through in the OpenAPI Specification and Postman collection.

api.yml
1name: api
2docs: |
3 ## Header
4 This API provides access to...

API version

You can define your header-based API versioning scheme, such as an X-API-Version. The supported versions and default value are specified like so:

api.yml
1version:
2 header: X-API-Version
3 default: "2.0.0"
4 values:
5 - "1.0.0"
6 - "2.0.0"
7 - "latest"