feat(swagger-object) : Improve object creation by ref and add enum

Add management of enumeration
Add support of enumeration inside creation by instance of Swagger::Object
Add refs for other Swagger::Object for non primitive type in creation by instance

(Related to icyleaf#18)

TODO : add spec for enumeration addition

spec/swagger/object_spec.cr

@@ -1,9 +1,23 @@
 require "../spec_helper"
 
+struct Author
+  property name
+
+  def initialize(@name : String)
+  end
+end
+
+enum VCS
+  GIT
+  SUBVERSION
+  MERCURIAL
+  FOSSIL
+end
+
 struct Project
-  property id, name, description, vcs, open_source
+  property id, name, description, vcs, open_source, author
 
-  def initialize(@id : Int32, @name : String, @vcs : String, @open_source : Bool, @description : String? = nil)
+  def initialize(@id : Int32, @name : String, @vcs : VCS, @open_source : Bool, @author : Author, @description : String? = nil)
   end
 end
 
@@ -49,23 +63,54 @@ describe Swagger::Object do
       raw.items.should eq("Comment")
     end
 
-    it "should generate schema of object from object instance" do
+    it "should generate schema of object with ref from object instance" do
       raw = Swagger::Object.create_from_instance(
-        Project.new(1, "swagger", "git", true, "Swagger contains a OpenAPI / Swagger universal documentation generator and HTTP server handler.")
+        Project.new(1,
+          "swagger", VCS::GIT, true,
+          Author.new("icyleaf"),
+          "Swagger contains a OpenAPI / Swagger universal documentation generator and HTTP server handler."),
+        refs: {Author => "Author"},
       )
       raw.name.should eq "Project"
       raw.type.should eq "object"
+      raw.items.should be nil
       raw.properties.should eq [
         Swagger::Property.new("id", "integer", "int32", example: 1, required: true),
         Swagger::Property.new("name", example: "swagger", required: true),
-        Swagger::Property.new("vcs", example: "git", required: true),
+        Swagger::Property.new("vcs", "object", example: "GIT", required: true, enum_values: [
+          "GIT", "SUBVERSION", "MERCURIAL", "FOSSIL",
+        ]),
         Swagger::Property.new("open_source", "boolean", example: true, required: true),
+        Swagger::Property.new("author", "object", required: true, ref: "Author"),
         Swagger::Property.new(
           "description",
           example: "Swagger contains a OpenAPI / Swagger universal documentation generator and HTTP server handler.",
           required: false
         ),
       ]
     end
+
+    it "shouldn't generate schema of object without ref from object instance" do
+      expect_raises(Swagger::Object::RefResolutionException, "No refs provided !") do
+        Swagger::Object.create_from_instance(
+          Project.new(1,
+            "swagger", VCS::GIT, true,
+            Author.new("icyleaf"),
+            "Swagger contains a OpenAPI / Swagger universal documentation generator and HTTP server handler.")
+        )
+      end
+    end
+
+    it "shouldn't generate schema of object without correct ref from object instance" do
+      expect_raises(Swagger::Object::RefResolutionException, "Ref for Author not found") do
+        Swagger::Object.create_from_instance(
+          Project.new(1,
+            "swagger", VCS::GIT, true,
+            Author.new("icyleaf"),
+            "Swagger contains a OpenAPI / Swagger universal documentation generator and HTTP server handler."),
+          refs: {Hash => "Hash"},
+        )
+      end
+    end
   end
 end

src/swagger/builder.cr

@@ -153,6 +153,7 @@ module Swagger
           type: property.type,
           description: property.description,
           example: property.example,
+          enum_values: property.enum_values,
         )
       end
     end

src/swagger/object.cr

@@ -22,31 +22,55 @@ module Swagger
                    @items : (self | String)? = nil)
     end
 
-    def self.create_from_instance(reflecting instance : T, custom_name : String? = nil) forall T
+    def self.create_from_instance(reflecting instance : T, custom_name : String? = nil, refs : Hash(Class, (String | self))? = nil) forall T
       {% begin %}
         properties = [] of Property
         {% for ivar in T.instance.instance_vars %}
           {{ iname = ivar.name.stringify }}
           swagger_data_type = Utils::SwaggerDataType.create_from_class({{ ivar.type }})
           {{ irequired = !ivar.type.union? }}
           value = {% if T.class? || T.struct? %} instance.{{ ivar.name }} {% else %} {{ ivar.default_value.stringify }} {% end %}
+          {% if ivar.type.union? %}
+            {{ type_ivar = ivar.type.union_types.find { |var| var != Nil } }}
+          {% else %}
+            {{ type_ivar = ivar.type }}
+          {% end %}
           properties << Property.new(
             {{ iname }},
             swagger_data_type.type,
             format: swagger_data_type.format,
-            {% if ivar.type <= String || ivar.type <= Int32 ||
-                    ivar.type <= Int64 || ivar.type <= Float64 ||
-                    ivar.type <= Bool %}
+            {% if type_ivar <= String || type_ivar <= Int32 ||
+                    type_ivar <= Int64 || type_ivar <= Float64 ||
+                    type_ivar <= Bool %}
               example: value,
-            {% else %}
+            {% elsif type_ivar <= Enum %}
               example: value.to_s,
+              enum_values: {{ type_ivar }}.names,
+            {% else %}
+              ref: resolve_ref({{ type_ivar }}, refs),
             {% end %}
-            required: {{ irequired }}
+            required: {{ irequired }},
           )
         {% end %}
 
         self.new(custom_name ? custom_name.as(String) : instance.class.name, "object", properties)
       {% end %}
     end
+
+    class RefResolutionException < Exception
+    end
+
+    private def self.resolve_ref(type : T.class, refs : Hash(Class, (String | self))? = nil) : String forall T
+      if refs.nil?
+        raise RefResolutionException.new("No refs provided !")
+      end
+
+      current_ref = refs[type]?
+      if current_ref.nil?
+        raise RefResolutionException.new("Ref for #{type} not found")
+      end
+
+      return current_ref.is_a?(String) ? current_ref : current_ref.name
+    end
   end
 end

src/swagger/objects/property.cr

@@ -12,14 +12,17 @@ module Swagger::Objects
     getter default : (String | Int32 | Int64 | Float64 | Bool)? = nil
     getter example : (String | Int32 | Int64 | Float64 | Bool)? = nil
     getter required : Bool? = nil
+    @[JSON::Field(key: "enum")]
+    getter enum_values : Array(String)? = nil
 
     @[JSON::Field(key: "$ref")]
     getter ref : String? = nil
 
     def initialize(@type : String? = nil, @description : String? = nil, @items : Schema? = nil,
                    @default : (String | Int32 | Int64 | Float64 | Bool)? = nil,
                    @example : (String | Int32 | Int64 | Float64 | Bool)? = nil,
-                   @required : Bool? = nil, @ref : String? = nil,)
+                   @required : Bool? = nil, @ref : String? = nil,
+                   @enum_values : Array(String)? = nil)
     end
   end
 end

src/swagger/property.cr

@@ -9,12 +9,14 @@ module Swagger
     property example
     property required
     property ref
+    property enum_values
 
     def initialize(@name : String, @type : String = "string", @format : String? = nil,
                    @items : (Object | String)? = nil, @description : String? = nil,
                    @default_value : (String | Int32 | Int64 | Float64 | Bool)? = nil,
                    @example : (String | Int32 | Int64 | Float64 | Bool)? = nil,
-                   @required : Bool? = nil, @ref : String? = nil)
+                   @required : Bool? = nil, @ref : String? = nil,
+                   @enum_values : Array(String)? = nil)
     end
   end
 end

src/swagger/utils.cr

@@ -12,7 +12,7 @@ module Utils
           return self.create_from_class({{ T.union_types.find { |var| var != Nil } }})
         {% else %}
           # Cf https://swagger.io/specification/#data-types
-          {% if T <= String || T <= Nil %}
+          {% if T <= String %}
             swagger_type = "string"
             swagger_format = nil
           {% elsif T <= Int %}
@@ -37,7 +37,7 @@ module Utils
             swagger_type = "boolean"
             swagger_format = nil
           {% else %}
-            swagger_type = {{ T.stringify }}
+            swagger_type = "object"
             swagger_format = nil
           {% end %}
           return self.new(swagger_type, swagger_format)