refactor: test: dynamic function handler

internal/dynfunc/handler.go

@@ -11,7 +11,7 @@ import (
 
 // Handler represents a dynamic api handler
 type Handler struct {
-	spec *spec
+	spec *signature
 	fn   interface{}
 	// whether fn uses api.Ctx as 1st argument
 	hasContext bool
@@ -26,11 +26,12 @@ type Handler struct {
 //  - `outputStruct` is a struct{} containing a field for each service output (with valid reflect.Type)
 //
 // Special cases:
+//  - a first optional input parameter of type `api.Ctx` can be added
 //  - it there is no input, `inputStruct` must be omitted
 //  - it there is no output, `outputStruct` must be omitted
 func Build(fn interface{}, service config.Service) (*Handler, error) {
 	h := &Handler{
-		spec: makeSpec(service),
+		spec: signatureFromService(service),
 		fn:   fn,
 	}
 
@@ -81,8 +82,8 @@ func (h *Handler) Handle(ctx api.Ctx, data map[string]interface{}) (map[string]i
 			}
 
 			// get value from @data
-			value, inData := data[name]
-			if !inData {
+			value, provided := data[name]
+			if !provided {
 				continue
 			}
 
@@ -93,7 +94,7 @@ func (h *Handler) Handle(ctx api.Ctx, data map[string]interface{}) (map[string]i
 				var ptrType = field.Type().Elem()
 
 				if !refvalue.Type().ConvertibleTo(ptrType) {
-					log.Printf("Cannot convert %v into %v", refvalue.Type(), ptrType)
+					log.Printf("Cannot convert %v into *%v", refvalue.Type(), ptrType)
 					return nil, api.ErrUncallableService
 				}
 
@@ -103,12 +104,13 @@ func (h *Handler) Handle(ctx api.Ctx, data map[string]interface{}) (map[string]i
 				field.Set(ptr)
 				continue
 			}
+
 			if !reflect.ValueOf(value).Type().ConvertibleTo(field.Type()) {
 				log.Printf("Cannot convert %v into %v", reflect.ValueOf(value).Type(), field.Type())
 				return nil, api.ErrUncallableService
 			}
 
-			field.Set(reflect.ValueOf(value).Convert(field.Type()))
+			field.Set(refvalue.Convert(field.Type()))
 		}
 		callArgs = append(callArgs, callStruct)
 	}

internal/dynfunc/handler_test.go

@@ -0,0 +1,173 @@
+package dynfunc
+
+import (
+	"fmt"
+	"reflect"
+	"testing"
+
+	"git.xdrm.io/go/aicra/api"
+)
+
+type testsignature signature
+
+// builds a mock service with provided arguments as Input and matched as Output
+func (s *testsignature) withArgs(dtypes ...reflect.Type) *testsignature {
+	if s.Input == nil {
+		s.Input = make(map[string]reflect.Type)
+	}
+	if s.Output == nil {
+		s.Output = make(map[string]reflect.Type)
+	}
+
+	for i, dtype := range dtypes {
+		name := fmt.Sprintf("P%d", i+1)
+		s.Input[name] = dtype
+		if dtype.Kind() == reflect.Ptr {
+			s.Output[name] = dtype.Elem()
+		} else {
+			s.Output[name] = dtype
+		}
+	}
+	return s
+}
+
+func TestInput(t *testing.T) {
+
+	type intstruct struct {
+		P1 int
+	}
+	type intptrstruct struct {
+		P1 *int
+	}
+
+	tcases := []struct {
+		Name           string
+		Spec           *testsignature
+		HasContext     bool
+		Fn             interface{}
+		Input          []interface{}
+		ExpectedOutput []interface{}
+		ExpectedErr    api.Err
+	}{
+		{
+			Name:           "none required none provided",
+			Spec:           (&testsignature{}).withArgs(),
+			Fn:             func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			HasContext:     false,
+			Input:          []interface{}{},
+			ExpectedOutput: []interface{}{},
+			ExpectedErr:    api.ErrSuccess,
+		},
+		{
+			Name: "int proxy (0)",
+			Spec: (&testsignature{}).withArgs(reflect.TypeOf(int(0))),
+			Fn: func(in intstruct) (*intstruct, api.Err) {
+				return &intstruct{P1: in.P1}, api.ErrSuccess
+			},
+			HasContext:     false,
+			Input:          []interface{}{int(0)},
+			ExpectedOutput: []interface{}{int(0)},
+			ExpectedErr:    api.ErrSuccess,
+		},
+		{
+			Name: "int proxy (11)",
+			Spec: (&testsignature{}).withArgs(reflect.TypeOf(int(0))),
+			Fn: func(in intstruct) (*intstruct, api.Err) {
+				return &intstruct{P1: in.P1}, api.ErrSuccess
+			},
+			HasContext:     false,
+			Input:          []interface{}{int(11)},
+			ExpectedOutput: []interface{}{int(11)},
+			ExpectedErr:    api.ErrSuccess,
+		},
+		{
+			Name: "*int proxy (nil)",
+			Spec: (&testsignature{}).withArgs(reflect.TypeOf(new(int))),
+			Fn: func(in intptrstruct) (*intptrstruct, api.Err) {
+				return &intptrstruct{P1: in.P1}, api.ErrSuccess
+			},
+			HasContext:     false,
+			Input:          []interface{}{},
+			ExpectedOutput: []interface{}{nil},
+			ExpectedErr:    api.ErrSuccess,
+		},
+		{
+			Name: "*int proxy (28)",
+			Spec: (&testsignature{}).withArgs(reflect.TypeOf(new(int))),
+			Fn: func(in intptrstruct) (*intstruct, api.Err) {
+				return &intstruct{P1: *in.P1}, api.ErrSuccess
+			},
+			HasContext:     false,
+			Input:          []interface{}{28},
+			ExpectedOutput: []interface{}{28},
+			ExpectedErr:    api.ErrSuccess,
+		},
+		{
+			Name: "*int proxy (13)",
+			Spec: (&testsignature{}).withArgs(reflect.TypeOf(new(int))),
+			Fn: func(in intptrstruct) (*intstruct, api.Err) {
+				return &intstruct{P1: *in.P1}, api.ErrSuccess
+			},
+			HasContext:     false,
+			Input:          []interface{}{13},
+			ExpectedOutput: []interface{}{13},
+			ExpectedErr:    api.ErrSuccess,
+		},
+	}
+
+	for _, tcase := range tcases {
+		t.Run(tcase.Name, func(t *testing.T) {
+			t.Parallel()
+
+			var dataIndex = 0
+			if tcase.HasContext {
+				dataIndex = 1
+			}
+
+			var handler = &Handler{
+				spec:       &signature{Input: tcase.Spec.Input, Output: tcase.Spec.Output},
+				fn:         tcase.Fn,
+				dataIndex:  dataIndex,
+				hasContext: tcase.HasContext,
+			}
+
+			// build input
+			input := make(map[string]interface{})
+			for i, val := range tcase.Input {
+				var key = fmt.Sprintf("P%d", i+1)
+				input[key] = val
+			}
+
+			var output, err = handler.Handle(api.Ctx{}, input)
+			if err != tcase.ExpectedErr {
+				t.Fatalf("expected api error <%v> got <%v>", tcase.ExpectedErr, err)
+			}
+
+			// check output
+			for i, expected := range tcase.ExpectedOutput {
+				var (
+					key         = fmt.Sprintf("P%d", i+1)
+					val, exists = output[key]
+				)
+				if !exists {
+					t.Fatalf("missing output[%s]", key)
+				}
+				if expected != val {
+					var (
+						expectedt   = reflect.ValueOf(expected)
+						valt        = reflect.ValueOf(val)
+						expectedNil = !expectedt.IsValid() || expectedt.Kind() == reflect.Ptr && expectedt.IsNil()
+						valNil      = !valt.IsValid() || valt.Kind() == reflect.Ptr && valt.IsNil()
+					)
+					// ignore both nil
+					if valNil && expectedNil {
+						continue
+					}
+					t.Fatalf("expected output[%s] to equal %T <%v> got %T <%v>", key, expected, expected, val, val)
+				}
+			}
+
+		})
+	}
+
+}

internal/dynfunc/signature.go

@@ -9,16 +9,15 @@ import (
 	"git.xdrm.io/go/aicra/internal/config"
 )
 
-type spec struct {
+// signature represents input/output arguments for a dynamic function
+type signature struct {
 	Input  map[string]reflect.Type
 	Output map[string]reflect.Type
-	// HasContext defines whether the given handler has api.Ctx as first argument
-	HasContext bool
 }
 
 // builds a spec from the configuration service
-func makeSpec(service config.Service) *spec {
-	s := &spec{
+func signatureFromService(service config.Service) *signature {
+	s := &signature{
 		Input:  make(map[string]reflect.Type),
 		Output: make(map[string]reflect.Type),
 	}
@@ -46,7 +45,7 @@ func makeSpec(service config.Service) *spec {
 }
 
 // checks for HandlerFn input arguments
-func (s *spec) checkInput(impl reflect.Type, index int) error {
+func (s *signature) checkInput(impl reflect.Type, index int) error {
 	var requiredInput, structIndex = index, index
 	if len(s.Input) > 0 { // arguments struct
 		requiredInput++
@@ -93,7 +92,7 @@ func (s *spec) checkInput(impl reflect.Type, index int) error {
 }
 
 // checks for HandlerFn output arguments
-func (s spec) checkOutput(impl reflect.Type) error {
+func (s signature) checkOutput(impl reflect.Type) error {
 	if impl.NumOut() < 1 {
 		return errMissingHandlerOutput
 	}

internal/dynfunc/signature_test.go

@@ -225,7 +225,7 @@ func TestInputCheck(t *testing.T) {
 			t.Parallel()
 
 			// mock spec
-			s := spec{
+			s := signature{
 				Input:  tcase.Input,
 				Output: nil,
 			}
@@ -371,7 +371,7 @@ func TestOutputCheck(t *testing.T) {
 			t.Parallel()
 
 			// mock spec
-			s := spec{
+			s := signature{
 				Input:  nil,
 				Output: tcase.Output,
 			}