GET method doesn't support body payload

[karol-lotkowski]

swagger-ui version: 2.1.2

For HTTP GET method Swagger UI doesn't send body payload.
I prepared endpoint (products/test) with simple request data (name field).
On 'Try it out' click the request to specified endpoint is done, but body payload is not included in the request.

Swagger UI test endpoint:

GET request without body payload:

Issue is strictly related with Swagger UI, because CURL command is correct:

curl -X GET --header "Accept: application/json" --header "Content-Type: application/json" --header "Authorization: Bearer ..." -d "{
  \"name\": \"test_name\"
}" "http://localhost:8080/application/products/test"

Execution of CURL command works as expected: body payload is send with HTTP GET method and match to REST API endpoint.

Based on the HTTP protocol specification GET method doesn't disallow body payload.

[fehguy]

Body payloads are not supported by swagger in a GET operation, and is typically not supported by any server frameworks, even though the http specification is vague about supporting them.

[lordent]

I think it's a good idea. The same principle works elastichsearch. This solution is convenient when you need to maintain the concept of REST API (read, create, update, and delete), and for the GET request is necessary to pass a sufficiently large amount of data.
For example, imagine an request report with lots of fields for aggregates, filters and sorts. Yes, even given the fact that all IDs have UUID format.

Yes, it is not as specified, but you are developing a tool, how to use it already solves the developer. Trimming functionality you force developers to do more possible bad decisions or make patches on your project.

[ehartford]

+1

The HTTP spec does not forbid using body on a GET.

De facto, a very popular server product (ElasticSearch) does use the body on a GET.

Regardless of previous convention, the scenario should be supported.

This is fallout from the move from "POST is for form submissions, GET is for page requests" way of thinking to "JavaScript calls RESTful APIs through AJAX and updates the DOM" way of thinking.

Logically, a request can be a GET (I am retrieving an entity) while the specification of the entity to retrieve can be too complex to put in the path or url parameters and so the right place to put it is in the body. (ie a JSON object)

[fehguy]

Read the HTTP spec. It specifically says that a body in a GET is not forbidden, however the server must ignore the value. We're not adding support for that in the tool in the short term.

[ehartford]

Perhaps you are looking at an older version of the spec?

In the current spec:
RFC 7230 3.3

The presence of a message body in a request is signaled by a
Content-Length or Transfer-Encoding header field.  Request message
framing is independent of method semantics, even if the method does
not define any use for a message body.

The sender's allowed to send a body in a GET.

RFC 7231 4.3.1

 A payload within a GET request message has no defined semantics;
 sending a payload body on a GET request might cause some existing
 implementations to reject the request.

I don't see any mandate to disregard the body of a GET.

[scarroll32]

I ran into the same issue, trying to send a body to a GET against Elasticsearch (which it supports). I solved the issue by using a POST instead and configuring Swagger that way.

[jconti]

Is there a possible compromise on this point? I work on internal API's where GET bodies are particularly useful to implement complex semantic search over a collection of tree-like objects. The real issue with GET bodies is the behavior of caching proxies. Caching proxies do not generally allow GET bodies as an optimization.

But I do not think API design should be limited by the implementation details of caching proxies. It may be however that the UI should not offer this unless the swagger spec specifically identifies body characteristics?

[webron]

@jconti tbh, I don't see that happening. In 3.0, we have explicitly expressed that payloads with not work for GET, DELETE and such.

[aseychell]

Swagger editor supports this functionality by converting the body into url encoded query string. Is this a possible approach to update the Swagger UI?

[webron]

Swagger Editor has been changed and will work the same as swagger-ui.

[mhvelplund]

Right now, the Java "jaxrs" server accepts and parses the body for GET requests, but the "csharp" client doesn't send them even if it generates code that allows you to specify it.