If :type is omitted, see if it's available in :using

CHANGELOG.md

@@ -1,5 +1,6 @@
 ### Next Release
 
+* [#196](https://github.com/tim-vandecasteele/grape-swagger/pull/196): If `:type` is omitted, see if it's available in `:using` - [@jhollinger](https://github.com/jhollinger).
 * Your contribution here.
 
 ### 0.9.0 (December 19, 2014)

README.md

@@ -229,7 +229,7 @@ end
 
 ### Relationships
 
-Put the full name of the relationship's class in `type`, leaving out any modules named `Entities` or `Entity`. So for the entity class `API::Entities::Address`, you would put `type: 'API::Address'`.
+You may safely omit `type` from relationships, as it can be inferred. However, if you need to specify or override it, use the full name of the class leaving out any modules named `Entities` or `Entity`.
 
 #### 1xN
 

lib/grape-swagger.rb

@@ -220,11 +220,17 @@ def parse_entity_models(models)
 
                   required << property_name.to_s if p.delete(:required)
 
+                  type = if p[:type]
+                           p.delete(:type)
+                         elsif (entity = model.exposures[property_name][:using])
+                           parse_entity_name(entity)
+                         end
+
                   if p.delete(:is_array)
-                    p[:items] = generate_typeref(p[:type])
+                    p[:items] = generate_typeref(type)
                     p[:type] = 'array'
                   else
-                    p.merge! generate_typeref(p.delete(:type))
+                    p.merge! generate_typeref(type)
                   end
 
                   # rename Grape Entity's "desc" to "description"

spec/response_model_spec.rb

@@ -11,13 +11,20 @@ class Kind < Grape::Entity
         class Something < Grape::Entity
           expose :text, documentation: { type: 'string', desc: 'Content of something.' }
           expose :kind, using: Kind, documentation: { type: 'MyAPI::Kind', desc: 'The kind of this something.' }
+          expose :kind2, using: Kind, documentation: { desc: 'Secondary kind.' }
+          expose :kind3, using: 'MyAPI::Entities::Kind', documentation: { desc: 'Tertiary kind.' }
+          expose :tags, using: 'MyAPI::Entities::Tag', documentation: { desc: 'Tags.', is_array: true }
           expose :relation, using: 'MyAPI::Entities::Relation', documentation: { type: 'MyAPI::Relation', desc: 'A related model.' }
         end
 
         class Relation < Grape::Entity
           expose :name, documentation: { type: 'string', desc: 'Name' }
         end
 
+        class Tag < Grape::Entity
+          expose :name, documentation: { type: 'string', desc: 'Name' }
+        end
+
         class Error < Grape::Entity
           expose :code, documentation: { type: 'string', desc: 'Error code' }
           expose :message, documentation: { type: 'string', desc: 'Error message' }
@@ -88,6 +95,9 @@ def app
       'properties' => {
         'text' => { 'type' => 'string', 'description' => 'Content of something.' },
         'kind' => { '$ref' => 'MyAPI::Kind', 'description' => 'The kind of this something.' },
+        'kind2' => { '$ref' => 'MyAPI::Kind', 'description' => 'Secondary kind.' },
+        'kind3' => { '$ref' => 'MyAPI::Kind', 'description' => 'Tertiary kind.' },
+        'tags' => { 'items' => { '$ref' => 'MyAPI::Tag' }, 'type' => 'array', 'description' => 'Tags.' },
         'relation' => { '$ref' => 'MyAPI::Relation', 'description' => 'A related model.' }
       }
     )