mirror of
https://github.com/adidas/api-guidelines.git
synced 2025-10-25 15:19:19 +00:00
31 lines
1.5 KiB
Markdown
31 lines
1.5 KiB
Markdown
# Content Negotiation
|
|
|
|
Every API **MUST** implement and every API Consumer **MUST** use the [HTTP content negotiation](https://tools.ietf.org/html/rfc7231#section-3.4) where a representation of a resource is requested.
|
|
|
|
> NOTE: The content negotiation plays the key role in evolving an API, **change management and versioning**.
|
|
|
|
## Example
|
|
|
|
A client is programmed to understand the `application/vnd.example.resource+json; version=2` message format semantics. The client requests a representation of the `/greeting` resource in desired the media type \(including its version\) from the server:
|
|
|
|
```text
|
|
GET /greeting HTTP/1.1
|
|
Accept: application/vnd.example.resource+json; version=2
|
|
...
|
|
```
|
|
|
|
The server can provide only a newer version of the requested media type `version=2.1.3`. But since the newer version is backward compatible with the requested `version=2` \(related: Changes & Versioning\) it can satisfy the request and responds:
|
|
|
|
```text
|
|
HTTP/1.1 200 OK
|
|
Content-Type: application/vnd.example.resource+json; version=2.1.3
|
|
...
|
|
```
|
|
|
|
> NOTE: A server that doesn't have the requested representation media type available **MUST** respond with the HTTP Status Code **406 Not Acceptable**.
|
|
>
|
|
> NOTE: A server **MAY** have multiple choices available and **MAY** respond with the **300 Multiple Choices** response. In which case client **SHOULD** choose from the presented choices.
|
|
>
|
|
> You can read more about content negotiation at [MDN Content negotiation](https://developer.mozilla.org/en-US/docs/Web/HTTP/Content_negotiation).
|
|
|