Title: RESTful API Versioning Desc: Learn about RESTful API versioning strategies supported by aah Go web framework. Keywords: restful api, rest api, api versioning, api version
This document provides an insights into REST API versioning strategies supported by aah
. API versioning allows you to alter behavior or application logic flow between different clients.
There are a number of valid strategies to approach API versioning. Typically API versioning is determined by the incoming client request, and may either be based on the request URL, request URL query parameter, request HTTP headers or HostName.
- Strategy: URL Path
- Strategy: Accept Header Versioning
- Strategy: Accept Header with Vendor Media Type
- Strategy: URL Query Parameter
- Strategy: HostName
Wondering: As of now, aah user have to fetch version
info according to versioning strategy they choose. Not sure, is it worth have one Method returns the version number based on chosen strategy. Let me know your thoughts.
This strategy requires the client to specify the version as part of the URL path.
For example:
GET /v1/users
Your routes.conf
include Named parameter with key as a version
. So that version info available to you in the controller via ctx.Req.PathValue("version")
.
routes {
path = "/:version"
routes {
path = "/users"
# ...
}
}
Tip:
URL Path based versioning strategy can be particularly useful if you have requirements to route incoming requests to different servers based on the version, as you can configure Request routing for different API versions.
This strategy requires the client to specify the version as part of the media type in the HTTP Accept
header. The version is included as a media type parameter, that supplements the main media type.
For example: HTTP request using the accept header versioning strategy.
GET /v1/users
Accept: application/json; version=2.0
You can access version
info via ctx.Req.AcceptContentType.Version()
.
This strategy requires the client to specify the version as part of the vendor media type in the HTTP Accept
header.
For example: HTTP request using the accept header with vendor media type strategy.
GET /v1/users
Accept: application/vnd.mycompany.myapp.customer-v2.2+json
You can access:
version
info usingctx.Req.AcceptContentType.Version()
vendor
info usingctx.Req.AcceptContentType.Vendor()
This strategy is a simple style that includes the version as a URL query parameter.
For example:
GET /users?version=1.1
You can access version
info via ctx.Req.QueryValue("version")
.
This strategy requires the client to specify the requested version as part of the hostname
in the URL.
For example:
# The following is an HTTP request to the URL: http://v1.sample.com/users/
GET /users
Host: v1.sample.com
You can access version
info via ctx.Subdomain()
.
Note:
The HostName strategy may need additional attention on developer machine to use in development/debug mode. Since you may have to configure local DNS mapping in you `host` file. This rackspace article covers the steps to modify-your-hosts-file for Mac, Linux and Windows
For example:
127.0.0.1 sample.com v1.sample.com
Tip:
HostName based versioning strategy can be particularly useful if you have requirements to route incoming requests to different servers based on the version, as you can configure different DNS records for different API versions.