Support for multiple query parameter combinations on a path

[gislikonrad]

Let's say you have these two routes in your API where the bold parameters are required.

1. GET - /values?type={type}
2. GET - /values?from={from}&to={to}

How would you describe this in Swagger 2.0?

Currently you can "hack" it by defining the route like the following.

paths:
 /values:
 get:
 summary: Get values
 parameters:
 - in: query
 name: type
 required: false
 type: string
 - in: query
 name: from
 required: false
 type: string
 format: date
 - in: query
 name: to
 required: false
 type: string
 format: date
 responses:
 '200':
 description: values
 schema:
 type: array
 items: 
 $ref: '#/definitions/value'

What this means is that the way the API is described, consumers could see it as being able to call GET - /values?type={type}&to={to}.

What I propose is a way to create a group or set of parameters and specify multiple possible groups or sets in a route. Example follows.

paths:
 /values:
 get:
 summary: Get values
 parameters:
 - $ref: '#/parameterSets/optional_type_filter'
 - $ref: '#/parameterSets/date_filter'
 responses:
 '200':
 description: values
 schema:
 type: array
 items: 
 $ref: '#/definitions/value'

parameterSets:
 optional_type_filter:
 - in: query
 name: type
 required: false
 type: string
 date_filter:
 - in: query
 name: from
 required: true
 type: string
 format: date
 - in: query
 name: to
 required: false
 type: string
 format: date

[VladRassokhin]

Looks like duplicate of #182

[webron]

This is a mix of #182 and #256, so let's keep the suggestions there. The suggested solution here introduces an additional level of complexity that will cause extra confusion with the potential parameter grouping in the future. I think the generic solution to #182 would be better in this case.