To proxy requests to an upstream API, you can simply use a combination of two FLAT Swagger enhancements:
wildcard paths, and
Imagine, the upstream API, you want to use, is located at https://upstream.api/api/docs
and provides a route to get a document with a certain ID (/get-doc/{docid}
). To set FLAT as a proxy to this API, the following swagger.yaml
snippet will do the job:
…basePath: /api…paths:/docs/**:x-flat-proxy:origin: https://upstream.api # replaces the origin…
Assuming a client origin of https://client.example.com
, a client request to e.g. https://client.example.com/api/docs/get-doc/42
will be proxied to https://upstream.api/api/docs/get-doc/42
.
Note, that only the origin is replaced, the path is not modified.
If the upstream API for docs is located at https://docs.upstream.api/v4
instead of https://upstream.api/api/docs
, the path has to be adjusted, too:
…basePath: /flat…paths:/docs/**:x-flat-proxy:origin: https://docs.upstream.apistripEndpoint: true # strips /flat/docs from the pathaddPrefix: /v4 # inserts /v4 before the stripped path…
The client request will be proxied to https://docs.upstream.api/v4/get-doc/42
.
Assuming you want to plug-in a different API (https://users.upstream/v3
), just add the following:
…/users/**:x-flat-proxy:origin: https://users.upstream.apistripEndpoint: true # strips /flat/users from the pathaddPrefix: /v3 # inserts /v3 before the stripped path
A client request to https://client.example.com/flat/users/profile/4711
will be proxied to https://users.upstream.api/v3/profile/4711
.