init

go.mod

@@ -0,0 +1,11 @@
+module github.com/insei/gomapper
+
+go 1.18
+
+require github.com/stretchr/testify v1.8.2
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

go.sum

@@ -0,0 +1,17 @@
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
+github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
+github.com/stretchr/testify v1.8.2 h1:+h33VjcLVPDHtOdpUCuF+7gSuG3yGIftsP1YvFihtJ8=
+github.com/stretchr/testify v1.8.2/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

mapper.go

@@ -0,0 +1,88 @@
+package gomapper
+
+import (
+	"fmt"
+	"reflect"
+)
+
+var routes = map[reflect.Type]map[reflect.Type]func(source interface{}, dest interface{}) error{}
+
+func AddRoute[TSource, TDest interface{}](mapFunc func(source TSource, dest TDest) error) error {
+	source := *new(TSource)
+	dest := *new(TDest)
+	destValueOf := reflect.ValueOf(dest)
+	if destValueOf.Kind() != reflect.Ptr {
+		return fmt.Errorf("destination object must be of reference type")
+	}
+	sourceValueOf := reflect.ValueOf(source)
+	if sourceValueOf.Kind() == reflect.Ptr {
+		return fmt.Errorf("source object must not be of reference type")
+	}
+	var route map[reflect.Type]func(source interface{}, dest interface{}) error
+	route, ok := routes[reflect.TypeOf(source)]
+	if !ok {
+		route = map[reflect.Type]func(source interface{}, dest interface{}) error{}
+		routes[reflect.TypeOf(source)] = route
+	}
+	funcConverted := func(source any, dest any) error {
+		sourceForMap := source
+		sourceValueOf := reflect.ValueOf(source)
+		if sourceValueOf.Kind() == reflect.Ptr {
+			sourceForMap = sourceValueOf.Elem().Interface()
+		}
+		return mapFunc(sourceForMap.(TSource), dest.(TDest))
+	}
+	route[reflect.TypeOf(dest)] = funcConverted
+	return nil
+}
+
+//Map source to dest
+func Map(source interface{}, dest interface{}) error {
+	if source == nil || dest == nil {
+		return fmt.Errorf("")
+	}
+	destValueOf := reflect.ValueOf(dest)
+	if destValueOf.Kind() != reflect.Ptr {
+		return fmt.Errorf("")
+	}
+
+	var sourceToMap any
+	sourceToMap = source
+	sourceValueOf := reflect.ValueOf(source)
+	if sourceValueOf.Kind() == reflect.Ptr {
+		sourceToMap = sourceValueOf.Elem().Interface()
+	}
+	route, ok := routes[reflect.TypeOf(sourceToMap)]
+	if !ok {
+		return fmt.Errorf("route not found")
+	}
+	mapFunc, ok := route[reflect.TypeOf(dest)]
+	if !ok {
+		return fmt.Errorf("route not found")
+	}
+	return mapFunc(source, dest)
+}
+
+// MapTo Map source to the new dest object
+func MapTo[TDest interface{}](source interface{}) (TDest, error) {
+	dest := new(TDest)
+	if source == nil {
+		return *dest, nil
+	}
+	var sourceToMap any
+	sourceToMap = source
+	sourceValueOf := reflect.ValueOf(source)
+	if sourceValueOf.Kind() == reflect.Ptr {
+		sourceToMap = sourceValueOf.Elem().Interface()
+	}
+	route, ok := routes[reflect.TypeOf(sourceToMap)]
+	if !ok {
+		return *dest, nil
+	}
+	mapFunc, ok := route[reflect.TypeOf(dest)]
+	if !ok {
+		return *dest, nil
+	}
+	err := mapFunc(source, dest)
+	return *dest, err
+}

mapper_test.go

@@ -0,0 +1,45 @@
+package gomapper
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type TestingStruct struct {
+	Name string
+}
+
+type TestingStruct2 struct {
+	Name string
+}
+
+func Test(t *testing.T) {
+	err := AddRoute[TestingStruct, *TestingStruct2](func(source TestingStruct, dest *TestingStruct2) error {
+		dest.Name = source.Name
+		return nil
+	})
+	assert.NoError(t, err)
+
+	source1 := &TestingStruct{Name: "Test1"}
+	dest1, err := MapTo[TestingStruct2](source1)
+	assert.NoError(t, err)
+	assert.Equal(t, source1.Name, dest1.Name)
+
+	source2 := TestingStruct{Name: "Test2"}
+	dest2, err := MapTo[TestingStruct2](source2)
+	assert.NoError(t, err)
+	assert.Equal(t, source2.Name, dest2.Name)
+
+	source3 := &TestingStruct{Name: "Test3"}
+	dest3 := &TestingStruct2{}
+	err = Map(source3, dest3)
+	assert.NoError(t, err)
+	assert.Equal(t, source3.Name, dest3.Name)
+
+	source4 := TestingStruct{Name: "Test4"}
+	dest4 := &TestingStruct2{}
+	err = Map(source4, dest4)
+	assert.NoError(t, err)
+	assert.Equal(t, source4.Name, dest4.Name)
+}