Merge pull request 'feature: add optional context to handlers' (#19) from feature/context into 0.3.0

An optional first input argument of type api.Ctx to handlers to access standard request/response

api/context.go

@@ -0,0 +1,17 @@
+package api
+
+import (
+	"net/http"
+)
+
+// Ctx contains additional information for handlers
+//
+// usually input/output arguments built by aicra are sufficient
+// but the Ctx lets you manage your request from scratch if required
+//
+// If required, set api.Ctx as the first argument of your handler; if you
+// don't need it, only use standard input arguments and it will be ignored
+type Ctx struct {
+	Res http.ResponseWriter
+	Req *http.Request
+}

builder.go

@@ -26,17 +26,18 @@ type apiHandler struct {
 }
 
 // AddType adds an available datatype to the api definition
-func (b *Builder) AddType(t datatype.T) {
+func (b *Builder) AddType(t datatype.T) error {
 	if b.conf == nil {
 		b.conf = &config.Server{}
 	}
 	if b.conf.Services != nil {
-		panic(errLateType)
+		return errLateType
 	}
 	if b.conf.Types == nil {
 		b.conf.Types = make([]datatype.T, 0)
 	}
 	b.conf.Types = append(b.conf.Types, t)
+	return nil
 }
 
 // Use adds an http adapter (middleware)

builder_test.go

@@ -0,0 +1,352 @@
+package aicra
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+
+	"git.xdrm.io/go/aicra/api"
+	"git.xdrm.io/go/aicra/datatype/builtin"
+)
+
+func addBuiltinTypes(b *Builder) error {
+	if err := b.AddType(builtin.AnyDataType{}); err != nil {
+		return err
+	}
+	if err := b.AddType(builtin.BoolDataType{}); err != nil {
+		return err
+	}
+	if err := b.AddType(builtin.FloatDataType{}); err != nil {
+		return err
+	}
+	if err := b.AddType(builtin.IntDataType{}); err != nil {
+		return err
+	}
+	if err := b.AddType(builtin.StringDataType{}); err != nil {
+		return err
+	}
+	if err := b.AddType(builtin.UintDataType{}); err != nil {
+		return err
+	}
+	return nil
+}
+
+func TestAddType(t *testing.T) {
+	builder := &Builder{}
+	err := builder.AddType(builtin.BoolDataType{})
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	err = builder.Setup(strings.NewReader("[]"))
+	if err != nil {
+		t.Fatalf("unexpected error: %s", err)
+	}
+	err = builder.AddType(builtin.FloatDataType{})
+	if err != errLateType {
+		t.Fatalf("expected <%v> got <%v>", errLateType, err)
+	}
+}
+
+func TestUse(t *testing.T) {
+	builder := &Builder{}
+	if err := addBuiltinTypes(builder); err != nil {
+		t.Fatalf("unexpected error <%v>", err)
+	}
+
+	// build @n middlewares that take data from context and increment it
+	n := 1024
+
+	type ckey int
+	const key ckey = 0
+
+	middleware := func(next http.HandlerFunc) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			newr := r
+
+			// first time -> store 1
+			value := r.Context().Value(key)
+			if value == nil {
+				newr = r.WithContext(context.WithValue(r.Context(), key, int(1)))
+				next(w, newr)
+				return
+			}
+
+			// get value and increment
+			cast, ok := value.(int)
+			if !ok {
+				t.Fatalf("value is not an int")
+			}
+			cast++
+			newr = r.WithContext(context.WithValue(r.Context(), key, cast))
+			next(w, newr)
+		}
+	}
+
+	// add middleware @n times
+	for i := 0; i < n; i++ {
+		builder.Use(middleware)
+	}
+
+	config := strings.NewReader(`[ { "method": "GET", "path": "/path", "scope": [[]], "info": "info", "in": {}, "out": {} } ]`)
+	err := builder.Setup(config)
+	if err != nil {
+		t.Fatalf("setup: unexpected error <%v>", err)
+	}
+
+	pathHandler := func(ctx api.Ctx) (*struct{}, api.Err) {
+		// write value from middlewares into response
+		value := ctx.Req.Context().Value(key)
+		if value == nil {
+			t.Fatalf("nothing found in context")
+		}
+		cast, ok := value.(int)
+		if !ok {
+			t.Fatalf("cannot cast context data to int")
+		}
+		// write to response
+		ctx.Res.Write([]byte(fmt.Sprintf("#%d#", cast)))
+
+		return nil, api.ErrSuccess
+	}
+
+	if err := builder.Bind(http.MethodGet, "/path", pathHandler); err != nil {
+		t.Fatalf("bind: unexpected error <%v>", err)
+	}
+
+	handler, err := builder.Build()
+	if err != nil {
+		t.Fatalf("build: unexpected error <%v>", err)
+	}
+
+	response := httptest.NewRecorder()
+	request := httptest.NewRequest(http.MethodGet, "/path", &bytes.Buffer{})
+
+	// test request
+	handler.ServeHTTP(response, request)
+	if response.Body == nil {
+		t.Fatalf("response has no body")
+	}
+	token := fmt.Sprintf("#%d#", n)
+	if !strings.Contains(response.Body.String(), token) {
+		t.Fatalf("expected '%s' to be in response <%s>", token, response.Body.String())
+	}
+
+}
+
+func TestBind(t *testing.T) {
+	tcases := []struct {
+		Name          string
+		Config        string
+		HandlerMethod string
+		HandlerPath   string
+		HandlerFn     interface{} // not bound if nil
+		BindErr       error
+		BuildErr      error
+	}{
+		{
+			Name:          "none required none provided",
+			Config:        "[]",
+			HandlerMethod: "",
+			HandlerPath:   "",
+			HandlerFn:     nil,
+			BindErr:       nil,
+			BuildErr:      nil,
+		},
+		{
+			Name:          "none required 1 provided",
+			Config:        "[]",
+			HandlerMethod: "",
+			HandlerPath:   "",
+			HandlerFn:     func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			BindErr:       errUnknownService,
+			BuildErr:      nil,
+		},
+		{
+			Name: "1 required none provided",
+			Config: `[
+				{
+					"method": "GET",
+					"path": "/path",
+					"scope": [[]],
+					"info": "info",
+					"in": {},
+					"out": {}
+				}
+			]`,
+			HandlerMethod: "",
+			HandlerPath:   "",
+			HandlerFn:     nil,
+			BindErr:       nil,
+			BuildErr:      errMissingHandler,
+		},
+		{
+			Name: "1 required wrong method provided",
+			Config: `[
+				{
+					"method": "GET",
+					"path": "/path",
+					"scope": [[]],
+					"info": "info",
+					"in": {},
+					"out": {}
+				}
+			]`,
+			HandlerMethod: http.MethodPost,
+			HandlerPath:   "/path",
+			HandlerFn:     func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			BindErr:       errUnknownService,
+			BuildErr:      errMissingHandler,
+		},
+		{
+			Name: "1 required wrong path provided",
+			Config: `[
+				{
+					"method": "GET",
+					"path": "/path",
+					"scope": [[]],
+					"info": "info",
+					"in": {},
+					"out": {}
+				}
+			]`,
+			HandlerMethod: http.MethodGet,
+			HandlerPath:   "/paths",
+			HandlerFn:     func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			BindErr:       errUnknownService,
+			BuildErr:      errMissingHandler,
+		},
+		{
+			Name: "1 required valid provided",
+			Config: `[
+				{
+					"method": "GET",
+					"path": "/path",
+					"scope": [[]],
+					"info": "info",
+					"in": {},
+					"out": {}
+				}
+			]`,
+			HandlerMethod: http.MethodGet,
+			HandlerPath:   "/path",
+			HandlerFn:     func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			BindErr:       nil,
+			BuildErr:      nil,
+		},
+		{
+			Name: "1 required with int",
+			Config: `[
+				{
+					"method": "GET",
+					"path": "/path",
+					"scope": [[]],
+					"info": "info",
+					"in": {
+						"id": { "info": "info", "type": "int", "name": "Name" }
+					},
+					"out": {}
+				}
+			]`,
+			HandlerMethod: http.MethodGet,
+			HandlerPath:   "/path",
+			HandlerFn:     func(struct{ Name int }) (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			BindErr:       nil,
+			BuildErr:      nil,
+		},
+		{
+			Name: "1 required with uint",
+			Config: `[
+				{
+					"method": "GET",
+					"path": "/path",
+					"scope": [[]],
+					"info": "info",
+					"in": {
+						"id": { "info": "info", "type": "uint", "name": "Name" }
+					},
+					"out": {}
+				}
+			]`,
+			HandlerMethod: http.MethodGet,
+			HandlerPath:   "/path",
+			HandlerFn:     func(struct{ Name uint }) (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			BindErr:       nil,
+			BuildErr:      nil,
+		},
+		{
+			Name: "1 required with string",
+			Config: `[
+				{
+					"method": "GET",
+					"path": "/path",
+					"scope": [[]],
+					"info": "info",
+					"in": {
+						"id": { "info": "info", "type": "string", "name": "Name" }
+					},
+					"out": {}
+				}
+			]`,
+			HandlerMethod: http.MethodGet,
+			HandlerPath:   "/path",
+			HandlerFn:     func(struct{ Name string }) (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			BindErr:       nil,
+			BuildErr:      nil,
+		},
+		{
+			Name: "1 required with bool",
+			Config: `[
+				{
+					"method": "GET",
+					"path": "/path",
+					"scope": [[]],
+					"info": "info",
+					"in": {
+						"id": { "info": "info", "type": "bool", "name": "Name" }
+					},
+					"out": {}
+				}
+			]`,
+			HandlerMethod: http.MethodGet,
+			HandlerPath:   "/path",
+			HandlerFn:     func(struct{ Name bool }) (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			BindErr:       nil,
+			BuildErr:      nil,
+		},
+	}
+
+	for _, tcase := range tcases {
+		t.Run(tcase.Name, func(t *testing.T) {
+			t.Parallel()
+
+			builder := &Builder{}
+
+			if err := addBuiltinTypes(builder); err != nil {
+				t.Fatalf("add built-in types: %s", err)
+			}
+
+			err := builder.Setup(strings.NewReader(tcase.Config))
+			if err != nil {
+				t.Fatalf("setup: unexpected error <%v>", err)
+			}
+
+			if tcase.HandlerFn != nil {
+				err := builder.Bind(tcase.HandlerMethod, tcase.HandlerPath, tcase.HandlerFn)
+				if !errors.Is(err, tcase.BindErr) {
+					t.Fatalf("bind: expected <%v> got <%v>", tcase.BindErr, err)
+				}
+			}
+
+			_, err = builder.Build()
+			if !errors.Is(err, tcase.BuildErr) {
+				t.Fatalf("build: expected <%v> got <%v>", tcase.BuildErr, err)
+			}
+
+		})
+	}
+}

handler.go

@@ -51,7 +51,8 @@ func (s Handler) handleRequest(w http.ResponseWriter, r *http.Request) {
 	}
 
 	// 5. pass execution to the handler
-	var outData, outErr = handler.dyn.Handle(input.Data)
+	ctx := api.Ctx{Res: w, Req: r}
+	var outData, outErr = handler.dyn.Handle(ctx, input.Data)
 
 	// 6. build res from returned data
 	var res = api.EmptyResponse().WithError(outErr)

internal/dynfunc/handler.go

@@ -11,8 +11,12 @@ 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
+	// index in input arguments where the data struct must be
+	dataIndex int
 }
 
 // Build a handler from a service configuration and a dynamic function
@@ -22,24 +26,30 @@ 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,
 	}
 
-	fnv := reflect.ValueOf(fn)
+	impl := reflect.TypeOf(fn)
 
-	if fnv.Type().Kind() != reflect.Func {
+	if impl.Kind() != reflect.Func {
 		return nil, errHandlerNotFunc
 	}
 
-	if err := h.spec.checkInput(fnv); err != nil {
+	h.hasContext = impl.NumIn() >= 1 && reflect.TypeOf(api.Ctx{}).AssignableTo(impl.In(0))
+	if h.hasContext {
+		h.dataIndex = 1
+	}
+
+	if err := h.spec.checkInput(impl, h.dataIndex); err != nil {
 		return nil, fmt.Errorf("input: %w", err)
 	}
-	if err := h.spec.checkOutput(fnv); err != nil {
+	if err := h.spec.checkOutput(impl); err != nil {
 		return nil, fmt.Errorf("output: %w", err)
 	}
 
@@ -47,14 +57,19 @@ func Build(fn interface{}, service config.Service) (*Handler, error) {
 }
 
 // Handle binds input @data into the dynamic function and returns map output
-func (h *Handler) Handle(data map[string]interface{}) (map[string]interface{}, api.Err) {
+func (h *Handler) Handle(ctx api.Ctx, data map[string]interface{}) (map[string]interface{}, api.Err) {
 	var ert = reflect.TypeOf(api.Err{})
 	var fnv = reflect.ValueOf(h.fn)
 
 	callArgs := []reflect.Value{}
 
+	// bind context if used in handler
+	if h.hasContext {
+		callArgs = append(callArgs, reflect.ValueOf(ctx))
+	}
+
 	// bind input data
-	if fnv.Type().NumIn() > 0 {
+	if fnv.Type().NumIn() > h.dataIndex {
 		// create zero value struct
 		callStructPtr := reflect.New(fnv.Type().In(0))
 		callStruct := callStructPtr.Elem()
@@ -67,8 +82,8 @@ func (h *Handler) Handle(data map[string]interface{}) (map[string]interface{}, a
 			}
 
 			// get value from @data
-			value, inData := data[name]
+			value, provided := data[name]
-			if !inData {
+			if !provided {
 				continue
 			}
 
@@ -79,7 +94,7 @@ func (h *Handler) Handle(data map[string]interface{}) (map[string]interface{}, a
 				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
 				}
 
@@ -89,12 +104,13 @@ func (h *Handler) Handle(data map[string]interface{}) (map[string]interface{}, a
 				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

@@ -9,14 +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
 }
 
 // builds a spec from the configuration service
-func makeSpec(service config.Service) spec {
+func signatureFromService(service config.Service) *signature {
-	spec := spec{
+	s := &signature{
 		Input:  make(map[string]reflect.Type),
 		Output: make(map[string]reflect.Type),
 	}
@@ -27,40 +28,46 @@ func makeSpec(service config.Service) spec {
 		}
 		// make a pointer if optional
 		if param.Optional {
-			spec.Input[param.Rename] = reflect.PtrTo(param.ExtractType)
+			s.Input[param.Rename] = reflect.PtrTo(param.ExtractType)
 			continue
 		}
-		spec.Input[param.Rename] = param.ExtractType
+		s.Input[param.Rename] = param.ExtractType
 	}
 
 	for _, param := range service.Output {
 		if len(param.Rename) < 1 {
 			continue
 		}
-		spec.Output[param.Rename] = param.ExtractType
+		s.Output[param.Rename] = param.ExtractType
 	}
 
-	return spec
+	return s
 }
 
 // checks for HandlerFn input arguments
-func (s spec) checkInput(fnv reflect.Value) error {
+func (s *signature) checkInput(impl reflect.Type, index int) error {
-	fnt := fnv.Type()
+	var requiredInput, structIndex = index, index
+	if len(s.Input) > 0 { // arguments struct
+		requiredInput++
+	}
 
-	// no input -> ok
+	// missing arguments
+	if impl.NumIn() > requiredInput {
+		return errUnexpectedInput
+	}
+
+	// none required
 	if len(s.Input) == 0 {
-		if fnt.NumIn() > 0 {
-			return errUnexpectedInput
-		}
 		return nil
 	}
 
-	if fnt.NumIn() != 1 {
+	// too much arguments
+	if impl.NumIn() != requiredInput {
 		return errMissingHandlerArgumentParam
 	}
 
 	// arg must be a struct
-	structArg := fnt.In(0)
+	structArg := impl.In(structIndex)
 	if structArg.Kind() != reflect.Struct {
 		return errMissingParamArgument
 	}
@@ -85,14 +92,13 @@ func (s spec) checkInput(fnv reflect.Value) error {
 }
 
 // checks for HandlerFn output arguments
-func (s spec) checkOutput(fnv reflect.Value) error {
+func (s signature) checkOutput(impl reflect.Type) error {
-	fnt := fnv.Type()
+	if impl.NumOut() < 1 {
-	if fnt.NumOut() < 1 {
 		return errMissingHandlerOutput
 	}
 
 	// last output must be api.Err
-	errOutput := fnt.Out(fnt.NumOut() - 1)
+	errOutput := impl.Out(impl.NumOut() - 1)
 	if !errOutput.AssignableTo(reflect.TypeOf(api.ErrUnknown)) {
 		return errMissingHandlerErrorOutput
 	}
@@ -102,12 +108,12 @@ func (s spec) checkOutput(fnv reflect.Value) error {
 		return nil
 	}
 
-	if fnt.NumOut() != 2 {
+	if impl.NumOut() != 2 {
 		return errMissingParamOutput
 	}
 
 	// fail if first output is not a pointer to struct
-	structOutputPtr := fnt.Out(0)
+	structOutputPtr := impl.Out(0)
 	if structOutputPtr.Kind() != reflect.Ptr {
 		return errMissingParamOutput
 	}

internal/dynfunc/signature_test.go

@@ -0,0 +1,397 @@
+package dynfunc
+
+import (
+	"errors"
+	"fmt"
+	"reflect"
+	"testing"
+
+	"git.xdrm.io/go/aicra/api"
+)
+
+func TestInputCheck(t *testing.T) {
+	tcases := []struct {
+		Name  string
+		Input map[string]reflect.Type
+		Fn    interface{}
+		FnCtx interface{}
+		Err   error
+	}{
+		{
+			Name:  "no input 0 given",
+			Input: map[string]reflect.Type{},
+			Fn:    func() {},
+			FnCtx: func(api.Ctx) {},
+			Err:   nil,
+		},
+		{
+			Name:  "no input 1 given",
+			Input: map[string]reflect.Type{},
+			Fn:    func(int) {},
+			FnCtx: func(api.Ctx, int) {},
+			Err:   errUnexpectedInput,
+		},
+		{
+			Name:  "no input 2 given",
+			Input: map[string]reflect.Type{},
+			Fn:    func(int, string) {},
+			FnCtx: func(api.Ctx, int, string) {},
+			Err:   errUnexpectedInput,
+		},
+		{
+			Name: "1 input 0 given",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:    func() {},
+			FnCtx: func(api.Ctx) {},
+			Err:   errMissingHandlerArgumentParam,
+		},
+		{
+			Name: "1 input non-struct given",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:    func(int) {},
+			FnCtx: func(api.Ctx, int) {},
+			Err:   errMissingParamArgument,
+		},
+		{
+			Name: "unexported input",
+			Input: map[string]reflect.Type{
+				"test1": reflect.TypeOf(int(0)),
+			},
+			Fn:    func(struct{}) {},
+			FnCtx: func(api.Ctx, struct{}) {},
+			Err:   errUnexportedName,
+		},
+		{
+			Name: "1 input empty struct given",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:    func(struct{}) {},
+			FnCtx: func(api.Ctx, struct{}) {},
+			Err:   errMissingParamFromConfig,
+		},
+		{
+			Name: "1 input invalid given",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:    func(struct{ Test1 string }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 string }) {},
+			Err:   errWrongParamTypeFromConfig,
+		},
+		{
+			Name: "1 input valid given",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:    func(struct{ Test1 int }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 int }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 input ptr empty struct given",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(new(int)),
+			},
+			Fn:    func(struct{}) {},
+			FnCtx: func(api.Ctx, struct{}) {},
+			Err:   errMissingParamFromConfig,
+		},
+		{
+			Name: "1 input ptr invalid given",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(new(int)),
+			},
+			Fn:    func(struct{ Test1 string }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 string }) {},
+			Err:   errWrongParamTypeFromConfig,
+		},
+		{
+			Name: "1 input ptr invalid ptr type given",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(new(int)),
+			},
+			Fn:    func(struct{ Test1 *string }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 *string }) {},
+			Err:   errWrongParamTypeFromConfig,
+		},
+		{
+			Name: "1 input ptr valid given",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(new(int)),
+			},
+			Fn:    func(struct{ Test1 *int }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 *int }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 valid string",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(string("")),
+			},
+			Fn:    func(struct{ Test1 string }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 string }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 valid uint",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(uint(0)),
+			},
+			Fn:    func(struct{ Test1 uint }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 uint }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 valid float64",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(float64(0)),
+			},
+			Fn:    func(struct{ Test1 float64 }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 float64 }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 valid []byte",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf([]byte("")),
+			},
+			Fn:    func(struct{ Test1 []byte }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 []byte }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 valid []rune",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf([]rune("")),
+			},
+			Fn:    func(struct{ Test1 []rune }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 []rune }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 valid *string",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(new(string)),
+			},
+			Fn:    func(struct{ Test1 *string }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 *string }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 valid *uint",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(new(uint)),
+			},
+			Fn:    func(struct{ Test1 *uint }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 *uint }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 valid *float64",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(new(float64)),
+			},
+			Fn:    func(struct{ Test1 *float64 }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 *float64 }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 valid *[]byte",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(new([]byte)),
+			},
+			Fn:    func(struct{ Test1 *[]byte }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 *[]byte }) {},
+			Err:   nil,
+		},
+		{
+			Name: "1 valid *[]rune",
+			Input: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(new([]rune)),
+			},
+			Fn:    func(struct{ Test1 *[]rune }) {},
+			FnCtx: func(api.Ctx, struct{ Test1 *[]rune }) {},
+			Err:   nil,
+		},
+	}
+
+	for _, tcase := range tcases {
+		t.Run(tcase.Name, func(t *testing.T) {
+			t.Parallel()
+
+			// mock spec
+			s := signature{
+				Input:  tcase.Input,
+				Output: nil,
+			}
+
+			t.Run("with-context", func(t *testing.T) {
+				err := s.checkInput(reflect.TypeOf(tcase.FnCtx), 1)
+				if err == nil && tcase.Err != nil {
+					t.Errorf("expected an error: '%s'", tcase.Err.Error())
+					t.FailNow()
+				}
+				if err != nil && tcase.Err == nil {
+					t.Errorf("unexpected error: '%s'", err.Error())
+					t.FailNow()
+				}
+
+				if err != nil && tcase.Err != nil {
+					if !errors.Is(err, tcase.Err) {
+						t.Errorf("expected the error <%s> got <%s>", tcase.Err, err)
+						t.FailNow()
+					}
+				}
+			})
+			t.Run("without-context", func(t *testing.T) {
+				err := s.checkInput(reflect.TypeOf(tcase.Fn), 0)
+				if err == nil && tcase.Err != nil {
+					t.Errorf("expected an error: '%s'", tcase.Err.Error())
+					t.FailNow()
+				}
+				if err != nil && tcase.Err == nil {
+					t.Errorf("unexpected error: '%s'", err.Error())
+					t.FailNow()
+				}
+
+				if err != nil && tcase.Err != nil {
+					if !errors.Is(err, tcase.Err) {
+						t.Errorf("expected the error <%s> got <%s>", tcase.Err, err)
+						t.FailNow()
+					}
+				}
+			})
+		})
+	}
+}
+
+func TestOutputCheck(t *testing.T) {
+	tcases := []struct {
+		Output map[string]reflect.Type
+		Fn     interface{}
+		Err    error
+	}{
+		// no input -> missing api.Err
+		{
+			Output: map[string]reflect.Type{},
+			Fn:     func() {},
+			Err:    errMissingHandlerOutput,
+		},
+		// no input -> with last type not api.Err
+		{
+			Output: map[string]reflect.Type{},
+			Fn:     func() bool { return true },
+			Err:    errMissingHandlerErrorOutput,
+		},
+		// no input -> with api.Err
+		{
+			Output: map[string]reflect.Type{},
+			Fn:     func() api.Err { return api.ErrSuccess },
+			Err:    nil,
+		},
+		// func can have output if not specified
+		{
+			Output: map[string]reflect.Type{},
+			Fn:     func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			Err:    nil,
+		},
+		// missing output struct in func
+		{
+			Output: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:  func() api.Err { return api.ErrSuccess },
+			Err: errMissingParamOutput,
+		},
+		// output not a pointer
+		{
+			Output: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:  func() (int, api.Err) { return 0, api.ErrSuccess },
+			Err: errMissingParamOutput,
+		},
+		// output not a pointer to struct
+		{
+			Output: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:  func() (*int, api.Err) { return nil, api.ErrSuccess },
+			Err: errMissingParamOutput,
+		},
+		// unexported param name
+		{
+			Output: map[string]reflect.Type{
+				"test1": reflect.TypeOf(int(0)),
+			},
+			Fn:  func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			Err: errUnexportedName,
+		},
+		// output field missing
+		{
+			Output: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:  func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
+			Err: errMissingParamFromConfig,
+		},
+		// output field invalid type
+		{
+			Output: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:  func() (*struct{ Test1 string }, api.Err) { return nil, api.ErrSuccess },
+			Err: errWrongParamTypeFromConfig,
+		},
+		// output field valid type
+		{
+			Output: map[string]reflect.Type{
+				"Test1": reflect.TypeOf(int(0)),
+			},
+			Fn:  func() (*struct{ Test1 int }, api.Err) { return nil, api.ErrSuccess },
+			Err: nil,
+		},
+		// ignore type check on nil type
+		{
+			Output: map[string]reflect.Type{
+				"Test1": nil,
+			},
+			Fn:  func() (*struct{ Test1 int }, api.Err) { return nil, api.ErrSuccess },
+			Err: nil,
+		},
+	}
+
+	for i, tcase := range tcases {
+		t.Run(fmt.Sprintf("case.%d", i), func(t *testing.T) {
+			t.Parallel()
+
+			// mock spec
+			s := signature{
+				Input:  nil,
+				Output: tcase.Output,
+			}
+
+			err := s.checkOutput(reflect.TypeOf(tcase.Fn))
+			if err == nil && tcase.Err != nil {
+				t.Errorf("expected an error: '%s'", tcase.Err.Error())
+				t.FailNow()
+			}
+			if err != nil && tcase.Err == nil {
+				t.Errorf("unexpected error: '%s'", err.Error())
+				t.FailNow()
+			}
+
+			if err != nil && tcase.Err != nil {
+				if !errors.Is(err, tcase.Err) {
+					t.Errorf("expected the error <%s> got <%s>", tcase.Err, err)
+					t.FailNow()
+				}
+			}
+		})
+	}
+}

internal/dynfunc/spec_test.go

@@ -1,230 +0,0 @@
-package dynfunc
-
-import (
-	"errors"
-	"fmt"
-	"reflect"
-	"testing"
-
-	"git.xdrm.io/go/aicra/api"
-)
-
-func TestInputCheck(t *testing.T) {
-	tcases := []struct {
-		Input map[string]reflect.Type
-		Fn    interface{}
-		Err   error
-	}{
-		// no input
-		{
-			Input: map[string]reflect.Type{},
-			Fn:    func() {},
-			Err:   nil,
-		},
-		// func must have noarguments if none specified
-		{
-			Input: map[string]reflect.Type{},
-			Fn:    func(int, string) {},
-			Err:   errUnexpectedInput,
-		},
-		// missing input struct in func
-		{
-			Input: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func() {},
-			Err: errMissingHandlerArgumentParam,
-		},
-		// input not a struct
-		{
-			Input: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func(int) {},
-			Err: errMissingParamArgument,
-		},
-		// unexported param name
-		{
-			Input: map[string]reflect.Type{
-				"test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func(struct{}) {},
-			Err: errUnexportedName,
-		},
-		// input field missing
-		{
-			Input: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func(struct{}) {},
-			Err: errMissingParamFromConfig,
-		},
-		// input field invalid type
-		{
-			Input: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func(struct{ Test1 string }) {},
-			Err: errWrongParamTypeFromConfig,
-		},
-		// input field valid type
-		{
-			Input: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func(struct{ Test1 int }) {},
-			Err: nil,
-		},
-	}
-
-	for i, tcase := range tcases {
-		t.Run(fmt.Sprintf("case.%d", i), func(t *testing.T) {
-			// mock spec
-			s := spec{
-				Input:  tcase.Input,
-				Output: nil,
-			}
-
-			err := s.checkInput(reflect.ValueOf(tcase.Fn))
-			if err == nil && tcase.Err != nil {
-				t.Errorf("expected an error: '%s'", tcase.Err.Error())
-				t.FailNow()
-			}
-			if err != nil && tcase.Err == nil {
-				t.Errorf("unexpected error: '%s'", err.Error())
-				t.FailNow()
-			}
-
-			if err != nil && tcase.Err != nil {
-				if !errors.Is(err, tcase.Err) {
-					t.Errorf("expected the error <%s> got <%s>", tcase.Err, err)
-					t.FailNow()
-				}
-			}
-		})
-	}
-}
-
-func TestOutputCheck(t *testing.T) {
-	tcases := []struct {
-		Output map[string]reflect.Type
-		Fn     interface{}
-		Err    error
-	}{
-		// no input -> missing api.Err
-		{
-			Output: map[string]reflect.Type{},
-			Fn:     func() {},
-			Err:    errMissingHandlerOutput,
-		},
-		// no input -> with last type not api.Err
-		{
-			Output: map[string]reflect.Type{},
-			Fn:     func() bool { return true },
-			Err:    errMissingHandlerErrorOutput,
-		},
-		// no input -> with api.Err
-		{
-			Output: map[string]reflect.Type{},
-			Fn:     func() api.Err { return api.ErrSuccess },
-			Err:    nil,
-		},
-		// func can have output if not specified
-		{
-			Output: map[string]reflect.Type{},
-			Fn:     func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
-			Err:    nil,
-		},
-		// missing output struct in func
-		{
-			Output: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func() api.Err { return api.ErrSuccess },
-			Err: errMissingParamOutput,
-		},
-		// output not a pointer
-		{
-			Output: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func() (int, api.Err) { return 0, api.ErrSuccess },
-			Err: errMissingParamOutput,
-		},
-		// output not a pointer to struct
-		{
-			Output: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func() (*int, api.Err) { return nil, api.ErrSuccess },
-			Err: errMissingParamOutput,
-		},
-		// unexported param name
-		{
-			Output: map[string]reflect.Type{
-				"test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
-			Err: errUnexportedName,
-		},
-		// output field missing
-		{
-			Output: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func() (*struct{}, api.Err) { return nil, api.ErrSuccess },
-			Err: errMissingParamFromConfig,
-		},
-		// output field invalid type
-		{
-			Output: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func() (*struct{ Test1 string }, api.Err) { return nil, api.ErrSuccess },
-			Err: errWrongParamTypeFromConfig,
-		},
-		// output field valid type
-		{
-			Output: map[string]reflect.Type{
-				"Test1": reflect.TypeOf(int(0)),
-			},
-			Fn:  func() (*struct{ Test1 int }, api.Err) { return nil, api.ErrSuccess },
-			Err: nil,
-		},
-		// ignore type check on nil type
-		{
-			Output: map[string]reflect.Type{
-				"Test1": nil,
-			},
-			Fn:  func() (*struct{ Test1 int }, api.Err) { return nil, api.ErrSuccess },
-			Err: nil,
-		},
-	}
-
-	for i, tcase := range tcases {
-		t.Run(fmt.Sprintf("case.%d", i), func(t *testing.T) {
-			// mock spec
-			s := spec{
-				Input:  nil,
-				Output: tcase.Output,
-			}
-
-			err := s.checkOutput(reflect.ValueOf(tcase.Fn))
-			if err == nil && tcase.Err != nil {
-				t.Errorf("expected an error: '%s'", tcase.Err.Error())
-				t.FailNow()
-			}
-			if err != nil && tcase.Err == nil {
-				t.Errorf("unexpected error: '%s'", err.Error())
-				t.FailNow()
-			}
-
-			if err != nil && tcase.Err != nil {
-				if !errors.Is(err, tcase.Err) {
-					t.Errorf("expected the error <%s> got <%s>", tcase.Err, err)
-					t.FailNow()
-				}
-			}
-		})
-	}
-}