Add json support to models (#50)

Fix #26

spec/model/model_spec.cr

@@ -563,6 +563,18 @@ module ModelSpec
         end
       end
 
+      it "can export to json" do
+        temporary do
+          reinit
+          u = User.new({first_name: "Hello", last_name: "World"})
+          u.to_json.should eq %({"first_name":"Hello","last_name":"World"})
+
+          u.to_json(full: true).should eq (
+            %({"id":null,"first_name":"Hello","last_name":"World","middle_name":null,"active":null,"notification_preferences":"null","updated_at":null,"created_at":null})
+          )
+        end
+      end
+
       it "can paginate with where clause" do
         temporary do
           reinit

spec/model/uuid_spec.cr

@@ -49,5 +49,20 @@ module UUIDSpec
         DBObject.query.where { id == "#{first_uuid}" }.count.should eq 1
       end
     end
+
+    it "can save a model with UUID to JSON" do
+      temporary do
+        reinit
+
+        3.times do |x|
+          DBObject.create!({name: "obj#{x}"})
+        end
+
+        (
+          DBObject.query.first!.to_json =~
+            /"id":"[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}"/
+        ).should eq 1
+      end
+    end
   end
 end

src/clear/extensions/core_ext.cr

@@ -0,0 +1,101 @@
+require "base64"
+
+struct Char
+  def to_json(json)
+    json.string("#{self}")
+  end
+end
+
+struct PG::Geo::Box
+  def to_json(json)
+    json.object do
+      json.field("x1") { json.number x1 }
+      json.field("x2") { json.number x2 }
+      json.field("y1") { json.number y1 }
+      json.field("y2") { json.number y2 }
+    end
+  end
+end
+
+struct PG::Geo::LineSegment
+  def to_json(json)
+    json.object do
+      json.field("x1") { json.number x1 }
+      json.field("x2") { json.number x2 }
+      json.field("y1") { json.number y1 }
+      json.field("y2") { json.number y2 }
+    end
+  end
+end
+
+struct PG::Geo::Point
+  def to_json(json)
+    json.object do
+      json.field("x") { json.number x }
+      json.field("y") { json.number y }
+    end
+  end
+end
+
+struct PG::Geo::Line
+  def to_json(json)
+    json.object do
+      json.field("a") { json.number a }
+      json.field("b") { json.number b }
+      json.field("c") { json.number c }
+    end
+  end
+end
+
+struct PG::Geo::Circle
+  def to_json(json)
+    json.object do
+      json.field("x") { json.number x }
+      json.field("y") { json.number y }
+      json.field("radius") { json.number radius }
+    end
+  end
+end
+
+struct PG::Geo::Path
+  def to_json(json)
+    json.object do
+      json.field("points") do
+        json.array do
+          points.each do
+            points.to_json(json)
+          end
+        end
+      end
+      json.field("closed") { json.bool(closed?) }
+    end
+  end
+end
+
+struct PG::Geo::Polygon
+  def to_json(json)
+    json.object do
+      json.array do
+        points.each do
+          points.to_json(json)
+        end
+      end
+    end
+  end
+end
+
+struct Slice(T)
+  def to_json(json)
+    s = String::Builder.new
+    to_s(s)
+    json.string(Base64.strict_encode(s.to_s))
+  end
+end
+
+struct PG::Numeric
+  def to_json(json)
+    s = String::Builder.new
+    to_s(s)
+    json.string(s.to_s)
+  end
+end

src/clear/model/model.cr

@@ -17,6 +17,7 @@ module Clear::Model
   include Clear::Model::HasRelations
   include Clear::Model::HasScope
   include Clear::Model::ClassMethods
+  include Clear::Model::HasJson
   include Clear::Model::IsPolymorphic
 
   getter cache : Clear::Model::QueryCache?

src/clear/model/modules/class_methods.cr

@@ -31,6 +31,13 @@ module Clear::Model::ClassMethods
 
       class_property pkey : String = "id"
 
+      # Collection({{@type}})
+      #
+      # This is the object managing a `Select` request.
+      # A new collection is created by calling `{{@type}}.query`
+      #
+      # Collection are mutable and refining the SQL will mutate the collection.
+      # You may want to copy the collection by calling `dup`
       class Collection < Clear::Model::CollectionBase(\{{@type}}); end
 
       def self.query

src/clear/model/modules/has_columns.cr

@@ -43,7 +43,7 @@ module Clear::Model::HasColumns
     {} of String => ::Clear::SQL::Any
   end
 
-  def to_h
+  def to_h(full = false)
     {} of String => ::Clear::SQL::Any
   end
 
@@ -196,11 +196,11 @@ module Clear::Model::HasColumns
     end
 
     # Return a hash version of the columns of this model.
-    def to_h : Hash(String, ::Clear::SQL::Any)
+    def to_h(full = false) : Hash(String, ::Clear::SQL::Any)
       out = super
 
       {% for name, settings in COLUMNS %}
-        if @{{name}}_column.defined?
+        if full || @{{name}}_column.defined?
           out[{{settings[:column_name]}}] = Clear::Model::Converter.to_db({{settings[:converter]}}, @{{name}}_column.value(nil))
         end
       {% end %}

src/clear/model/modules/has_json.cr

@@ -0,0 +1,9 @@
+module Clear::Model::HasJson
+  def to_json(full : Bool)
+    to_h(full).to_json
+  end
+
+  def to_json(json, full = false)
+    to_h(full).to_json(json)
+  end
+end

src/clear/model/modules/has_relations.cr

@@ -291,7 +291,7 @@ module Clear::Model::HasRelations
     end
 
     before(:validate, _bt_save_{{method_name}})
-    # Adding the eager loading
+
     class Collection
       def with_{{method_name}}(fetch_columns = false, &block : {{relation_type}}::Collection -> ) : self
         before_query do