func makeClosure(fv reflect.Value, ft reflect.Type) *function {
fn := &function{
call: fv,
}
var rt = Void
var at []Type
if n := ft.NumOut(); n != 0 {
rt = makeRetType(reflect.New(ft.Out(0)))
}
if n := ft.NumIn(); n != 0 {
at = make([]Type, n)
for i := 0; i != n; i++ {
at[i] = makeArgType(reflect.Zero(ft.In(i)))
}
}
fn.Interface = Prepare(rt, at...)
if err := constructClosure(fn); err != nil {
panic(err)
}
runtime.SetFinalizer(fn, destroyClosure)
return fn
}
// Add all necessary imports for the type, recursing as appropriate.
func addImportsForType(imports importMap, t reflect.Type) {
// Add any import needed for the type itself.
addImportForType(imports, t)
// Handle special cases where recursion is needed.
switch t.Kind() {
case reflect.Array, reflect.Chan, reflect.Ptr, reflect.Slice:
addImportsForType(imports, t.Elem())
case reflect.Func:
// Input parameters.
for i := 0; i < t.NumIn(); i++ {
addImportsForType(imports, t.In(i))
}
// Return values.
for i := 0; i < t.NumOut(); i++ {
addImportsForType(imports, t.Out(i))
}
case reflect.Map:
addImportsForType(imports, t.Key())
addImportsForType(imports, t.Elem())
}
}
func FormatFuncArguments(t reflect.Type) (decl string) {
decl = "("
in := make([]string, t.NumIn())
for i := range in {
in[i] = ValType(t.In(i))
}
decl += strings.Join(in, ",") + ")"
out := make([]string, t.NumOut())
if len(out) > 0 {
for i := range out {
out[i] = ValType(t.Out(i))
}
s := strings.Join(out, ",")
if len(out) != 1 {
s = "(" + s + ")"
}
decl += " " + s
}
return
}
// Note: Methods take the receiver as the first argument, which the want
// signature doesn't include.
func sigMatches(got, want reflect.Type) bool {
nin := want.NumIn()
if got.NumIn()-1 != nin {
return false
}
nout := want.NumOut()
if got.NumOut() != nout {
return false
}
for i := 0; i < nin; i++ {
if got.In(i+1) != want.In(i) {
return false
}
}
for i := 0; i < nout; i++ {
if got.Out(i) != want.Out(i) {
return false
}
}
return true
}
// Verifies whether a deep-copy function has a correct signature.
func verifyDeepCopyFunctionSignature(ft reflect.Type) error {
if ft.Kind() != reflect.Func {
return fmt.Errorf("expected func, got: %v", ft)
}
if ft.NumIn() != 3 {
return fmt.Errorf("expected three 'in' params, got $v", ft)
}
if ft.NumOut() != 1 {
return fmt.Errorf("expected one 'out' param, got %v", ft)
}
if ft.In(1).Kind() != reflect.Ptr {
return fmt.Errorf("expected pointer arg for 'in' param 1, got: %v", ft)
}
if ft.In(1).Elem() != ft.In(0) {
return fmt.Errorf("expected 'in' param 0 the same as param 1, got: %v", ft)
}
var forClonerType Cloner
if expected := reflect.TypeOf(&forClonerType); ft.In(2) != expected {
return fmt.Errorf("expected '%v' arg for 'in' param 2, got: '%v'", expected, ft.In(2))
}
var forErrorType error
// This convolution is necessary, otherwise TypeOf picks up on the fact
// that forErrorType is nil
errorType := reflect.TypeOf(&forErrorType).Elem()
if ft.Out(0) != errorType {
return fmt.Errorf("expected error return, got: %v", ft)
}
return nil
}
// t's Kind must be a reflect.Func.
func funcArgsFromType(t reflect.Type) (in []*Parameter, variadic *Parameter, out []*Parameter, err error) {
nin := t.NumIn()
if t.IsVariadic() {
nin--
}
var p *Parameter
for i := 0; i < nin; i++ {
p, err = parameterFromType(t.In(i))
if err != nil {
return
}
in = append(in, p)
}
if t.IsVariadic() {
p, err = parameterFromType(t.In(nin).Elem())
if err != nil {
return
}
variadic = p
}
for i := 0; i < t.NumOut(); i++ {
p, err = parameterFromType(t.Out(i))
if err != nil {
return
}
out = append(out, p)
}
return
}
// unify attempts to satisfy a pair of types, where the `param` type is the
// expected type of a function argument and the `input` type is the known
// type of a function argument. The `param` type may be parametric (that is,
// it may contain a type that is convertible to TypeVariable) but the
// `input` type may *not* be parametric.
//
// Any failure to unify the two types results in a panic.
//
// The end result of unification is a type environment: a set of substitutions
// from type variable to a Go type.
func (tp typePair) unify(param, input reflect.Type) error {
if tyname := tyvarName(input); len(tyname) > 0 {
return tp.error("Type variables are not allowed in the types of " +
"arguments.")
}
if tyname := tyvarName(param); len(tyname) > 0 {
if cur, ok := tp.tyenv[tyname]; ok && cur != input {
return tp.error("Type variable %s expected type '%s' but got '%s'.",
tyname, cur, input)
} else if !ok {
tp.tyenv[tyname] = input
}
return nil
}
if param.Kind() != input.Kind() {
return tp.error("Cannot unify different kinds of types '%s' and '%s'.",
param, input)
}
switch param.Kind() {
case reflect.Array:
return tp.unify(param.Elem(), input.Elem())
case reflect.Chan:
if param.ChanDir() != input.ChanDir() {
return tp.error("Cannot unify '%s' with '%s' "+
"(channel directions are different: '%s' != '%s').",
param, input, param.ChanDir(), input.ChanDir())
}
return tp.unify(param.Elem(), input.Elem())
case reflect.Func:
if param.NumIn() != input.NumIn() || param.NumOut() != input.NumOut() {
return tp.error("Cannot unify '%s' with '%s'.", param, input)
}
for i := 0; i < param.NumIn(); i++ {
if err := tp.unify(param.In(i), input.In(i)); err != nil {
return err
}
}
for i := 0; i < param.NumOut(); i++ {
if err := tp.unify(param.Out(i), input.Out(i)); err != nil {
return err
}
}
case reflect.Map:
if err := tp.unify(param.Key(), input.Key()); err != nil {
return err
}
return tp.unify(param.Elem(), input.Elem())
case reflect.Ptr:
return tp.unify(param.Elem(), input.Elem())
case reflect.Slice:
return tp.unify(param.Elem(), input.Elem())
}
// The only other container types are Interface and Struct.
// I am unsure about what to do with interfaces. Mind is fuzzy.
// Structs? I don't think it really makes much sense to use type
// variables inside of them.
return nil
}
func (ms *GobMarshaller) Prepare(name string, fn interface{}) (err error) {
var (
fT reflect.Type
)
// Gob needs to register type before encode/decode
if fT = reflect.TypeOf(fn); fT.Kind() != reflect.Func {
err = fmt.Errorf("fn is not a function but %v", fn)
return
}
reg := func(v reflect.Value) (err error) {
if !v.CanInterface() {
err = fmt.Errorf("Can't convert to value in input of %v for name:%v", fn, name)
return
}
gob.Register(v.Interface())
return
}
for i := 0; i < fT.NumIn(); i++ {
// create a zero value of the type of parameters
if err = reg(reflect.Zero(fT.In(i))); err != nil {
return
}
}
for i := 0; i < fT.NumOut(); i++ {
if err = reg(reflect.Zero(fT.Out(i))); err != nil {
return
}
}
return
}
func typeString_FuncOrMethod(
name string,
t reflect.Type,
pkgPath string) (s string) {
// Deal with input types.
var in []string
for i := 0; i < t.NumIn(); i++ {
in = append(in, typeString(t.In(i), pkgPath))
}
// And output types.
var out []string
for i := 0; i < t.NumOut(); i++ {
out = append(out, typeString(t.Out(i), pkgPath))
}
// Put it all together.
s = fmt.Sprintf(
"%s(%s) (%s)",
name,
strings.Join(in, ", "),
strings.Join(out, ", "))
return
}
func (p *MethodMetadata) IsEqual(t reflect.Type) bool {
if t.ConvertibleTo(p.Method.Type) {
return false
}
baseIndex := 0
if p.Method.Index >= 0 {
baseIndex = 1
}
if t.NumIn()+baseIndex != p.Method.Type.NumIn() {
return false
}
for i := 0; i < p.Method.Type.NumIn()-baseIndex; i++ {
if p.Method.Type.In(baseIndex+i) != t.In(i) {
return false
}
}
for i := 0; i < p.Method.Type.NumOut(); i++ {
if p.Method.Type.Out(baseIndex+i) != t.Out(i) {
return false
}
}
return true
}
func InTypes(fnType reflect.Type) []reflect.Type {
var types []reflect.Type
for i := 0; i < fnType.NumIn(); i++ {
types = append(types, fnType.In(i))
}
return types
}
func checkFunc(fnType reflect.Type) (bool, error) {
var state State
foundState := 0
nin := fnType.NumIn()
for i := 0; i < nin; i++ {
if fnType.In(i) == reflect.TypeOf(state) {
foundState++
} else if fnType.In(i) == reflect.TypeOf(&state) {
return false, fmt.Errorf("raw function can not use `*State' as arg, instead using `State'")
}
}
wrongRawFunc := false
if foundState > 1 {
wrongRawFunc = true
} else if foundState == 1 {
nout := fnType.NumOut()
if nin != 1 || nout != 1 {
wrongRawFunc = true
} else {
if fnType.Out(0).Kind() != reflect.Int {
wrongRawFunc = true
}
}
}
if wrongRawFunc {
return false, fmt.Errorf("raw function must be type: `func(State) int'")
}
return true, nil
}
// BuildArgs creates an args slice than can be used to make a f.Call(args)
func BuildArgs(t crossdock.T, desc string, ft reflect.Type, give []interface{}, initialArgs int) (_ []reflect.Value, ok bool) {
check := crossdock.Checks(t)
wantIn := len(give) + initialArgs // +2 for ctx and reqMeta
if !check.Equal(wantIn, ft.NumIn(), "%v: should accept %d arguments", desc, wantIn) {
return nil, false
}
var args []reflect.Value
for i, v := range give {
var val reflect.Value
vt := ft.In(i + initialArgs)
if v == nil {
// nil is an invalid argument to ValueOf. For nil, use the zero
// value for that argument.
val = reflect.Zero(vt)
} else {
val = reflect.ValueOf(v)
}
if !check.Equal(vt, val.Type(), "%v: argument %v type mismatch", desc, i) {
return nil, false
}
args = append(args, val)
}
return args, true
}
// Get all the parameters setup for invocation.
func (method ApiMethod) createArguments(userId UserId, userName UserName, token Token, response http.ResponseWriter, request *http.Request) (bool, []reflect.Value) {
var handlerType reflect.Type = reflect.TypeOf(method.handler)
var numParams int = handlerType.NumIn()
var apiParamIndex = 0
var paramValues []reflect.Value = make([]reflect.Value, numParams)
for i := 0; i < numParams; i++ {
var ParamType reflect.Type = handlerType.In(i)
// The user id, token, request, and response get handled specially.
if method.auth && ParamType.String() == "goapi.Token" {
paramValues[i] = reflect.ValueOf(token)
} else if method.auth && ParamType.String() == "goapi.UserId" {
paramValues[i] = reflect.ValueOf(userId)
} else if method.auth && ParamType.String() == "goapi.UserName" {
paramValues[i] = reflect.ValueOf(userName)
} else if ParamType.String() == "*http.Request" {
paramValues[i] = reflect.ValueOf(request)
} else if ParamType.String() == "http.ResponseWriter" {
paramValues[i] = reflect.ValueOf(response)
} else {
// Normal param, fetch the next api parameter and pass it along.
ok, val := method.fetchParam(apiParamIndex, request)
if !ok {
return false, []reflect.Value{}
}
paramValues[i] = val
apiParamIndex++
}
}
return true, paramValues
}
func args(f reflect.Type) []reflect.Type {
in := make([]reflect.Type, f.NumIn())
for i := 0; i < f.NumIn(); i++ {
in[i] = f.In(i)
}
return in
}
func methSigMatches(got reflect.Type, _want interface{}) error {
// Note: Methods take the receiver as the first argument, which the want
// signature doesn't include.
if got.NumIn() == 0 {
// The receiver is missing!
return fmt.Errorf("Method without reciever!")
}
want := reflect.TypeOf(_want)
if got.NumIn()-1 != want.NumIn() {
return fmt.Errorf("Method should have %d arguments, not %d", want.NumIn(), got.NumIn()-1)
}
if got.NumOut() != want.NumOut() {
return fmt.Errorf("Method should have %d return values, not %d", want.NumOut(), got.NumOut())
}
for i := 0; i < want.NumIn(); i++ {
if got.In(i+1) != want.In(i) {
return fmt.Errorf("Method argument %d should be %v, not %v", i+1, want.In(i), got.In(i+1))
}
}
for i := 0; i < want.NumOut(); i++ {
if got.Out(i) != want.Out(i) {
return fmt.Errorf("Method return value %d should be %v, not %v", i+1, want.Out(i), got.Out(i))
}
}
return nil
}
func genArgs(fnType reflect.Type, args []interface{}) []reflect.Value {
expectNArgs := fnType.NumIn()
actualNArgs := len(args)
if expectNArgs != actualNArgs {
panic(fmt.Sprintf("the function %s expect %d arguments, acctually get %d arguments", fnType, expectNArgs, actualNArgs))
}
argsValues := make([]reflect.Value, expectNArgs)
for i, arg := range args {
argType := fnType.In(i)
argValue := reflect.ValueOf(arg)
if !argValue.IsValid() {
argValue = reflect.Zero(argType)
}
actualType := argValue.Type()
if argType != actualType && !actualType.Implements(argType) {
// TODO: change %dth to %dst, %dnd, %drd, %dth.
panic(fmt.Sprintf("the %dth argument on function %s gets wrong type: expect %v, actually get %v", i, fnType, argType, actualType))
}
argsValues[i] = argValue
}
return argsValues
}
//should the context be passed to the handler?
func requiresContext(handlerType reflect.Type) bool {
//fmt.Printf("type %v\n", handlerType)
//if the method doesn't take arguments, no
if handlerType.NumIn() == 0 {
return false
}
//if the first argument is not a pointer, no
a0 := handlerType.In(0)
if a0.Kind() != reflect.Ptr {
return false
}
//if the first argument is a context, yes
if a0.Elem() == contextType {
return true
}
//another case -- the first argument is a method receiver, and the
//second argument is a web.Context
if handlerType.NumIn() > 1 {
a1 := handlerType.In(1)
if a1.Kind() != reflect.Ptr {
return false
}
if a1.Elem() == contextType {
return true
}
}
return false
}
func fixupArgs(t reflect.Type, v ...interface{}) []reflect.Value {
res := make([]reflect.Value, len(v))
for ix, vv := range v {
res[ix] = fixupArg(t.In(ix), vv)
}
return res
}
// verifyHandler ensures that the given t is a function with the following signature:
// func(json.Context, *ArgType)(*ResType, error)
func verifyHandler(t reflect.Type) error {
if t.NumIn() != 2 || t.NumOut() != 2 {
return fmt.Errorf("handler should be of format func(json.Context, *ArgType) (*ResType, error)")
}
isStructPtr := func(t reflect.Type) bool {
return t.Kind() == reflect.Ptr && t.Elem().Kind() == reflect.Struct
}
isMap := func(t reflect.Type) bool {
return t.Kind() == reflect.Map && t.Key().Kind() == reflect.String
}
validateArgRes := func(t reflect.Type, name string) error {
if !isStructPtr(t) && !isMap(t) {
return fmt.Errorf("%v should be a pointer to a struct, or a map[string]interface{}", name)
}
return nil
}
if t.In(0) != typeOfContext {
return fmt.Errorf("arg0 should be of type json.Context")
}
if err := validateArgRes(t.In(1), "second argument"); err != nil {
return err
}
if err := validateArgRes(t.Out(0), "first return value"); err != nil {
return err
}
if !t.Out(1).AssignableTo(typeOfError) {
return fmt.Errorf("second return value should be an error")
}
return nil
}
func GetMethodArgs(t reflect.Type) []reflect.Type {
l := t.NumIn() - 1
in := make([]reflect.Type, l)
for i := 0; i < l; i++ {
in[i] = t.In(i + 1)
}
return in
}
func GetFuncArgs(t reflect.Type) []reflect.Type {
l := t.NumIn()
in := make([]reflect.Type, l)
for i := 0; i < l; i++ {
in[i] = t.In(i)
}
return in
}
func getInputTypeString(i int, ft reflect.Type) string {
numInputs := ft.NumIn()
if i == numInputs-1 && ft.IsVariadic() {
return "..." + getTypeString(ft.In(i).Elem())
}
return getTypeString(ft.In(i))
}
// safeNumericConvert converts numeric parameter val from js to the type that the function fn expects if its safe to do so.
// This allows literals (int64) and the general js numeric form (float64) to be passed as parameters to go functions easily.
func safeNumericConvert(fn reflect.Type, i int, val interface{}) reflect.Value {
switch val.(type) {
default:
// Not a supported conversion
return reflect.ValueOf(val)
case float64, int64:
// What type is the func expecting?
var ptype reflect.Type
switch {
case fn.IsVariadic() && fn.NumIn() <= i+1:
// This argument is variadic so use the variadics element type.
ptype = fn.In(fn.NumIn() - 1).Elem()
case fn.NumIn() > i:
ptype = fn.In(i)
}
if f64, ok := val.(float64); ok {
switch ptype.Kind() {
case reflect.Float64:
return reflect.ValueOf(val)
case reflect.Float32:
if reflect.Zero(ptype).OverflowFloat(f64) {
// Not safe to convert
return reflect.ValueOf(val)
}
return reflect.ValueOf(val).Convert(ptype)
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
i64 := int64(f64)
if float64(i64) != f64 {
// Not safe to convert
return reflect.ValueOf(val)
}
// The float represents an integer
val = i64
default:
// Not a supported conversion
return reflect.ValueOf(val)
}
}
i64 := val.(int64)
switch ptype.Kind() {
case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32:
if !reflect.Zero(ptype).OverflowInt(i64) {
return reflect.ValueOf(val).Convert(ptype)
}
case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
if i64 > 0 && !reflect.Zero(ptype).OverflowUint(uint64(i64)) {
return reflect.ValueOf(val).Convert(ptype)
}
}
}
// Not a supported conversion
return reflect.ValueOf(val)
}
func funcIsBypass(t reflect.Type) bool {
if t.NumIn() == 1 && t.NumOut() == 1 && t.In(0) == refTypeLStatePtr && t.Out(0) == refTypeInt {
return true
}
if t.NumIn() == 2 && t.NumOut() == 1 && t.In(1) == refTypeLStatePtr && t.Out(0) == refTypeInt {
return true
}
return false
}
/**
* get func params
*
* @param funcType
* @param
*/
func (r *ReflectRouter) getFuncArgs(funcType reflect.Type, context *HttpContext) []reflect.Value {
argsNum := funcType.NumIn()
args := make([]reflect.Value, argsNum, argsNum)
for i := 0; i < argsNum; i++ {
in := funcType.In(i)
typeString := in.String()
var argsValue reflect.Value
switch typeString {
case "*http.Request":
argsValue = reflect.ValueOf(context.Request)
case "http.Request":
argsValue = reflect.ValueOf(context.Request).Elem()
case "*url.URL":
argsValue = reflect.ValueOf(context.Request.URL)
case "url.URL":
argsValue = reflect.ValueOf(context.Request.URL).Elem()
case "*leafveingo.HttpContext":
argsValue = reflect.ValueOf(context)
case "leafveingo.HttpContext":
argsValue = reflect.ValueOf(context).Elem()
case "[]uint8":
body := context.RequestBody()
if nil != body {
argsValue = reflect.ValueOf(body)
} else {
argsValue = reflect.Zero(in)
}
case "http.ResponseWriter":
argsValue = reflect.ValueOf(context.RespWrite)
case "LVSession.HttpSession":
session, _ := context.Session(false)
if nil != session {
argsValue = reflect.ValueOf(session)
} else {
argsValue = reflect.Zero(in)
}
default:
val, err := context.PackStructFormByRefType(in)
if nil == err {
argsValue = val
} else {
context.LVServer().Log().Debug(err.Error())
}
}
if reflect.Invalid == argsValue.Kind() {
argsValue = reflect.Zero(in)
}
args[i] = argsValue
}
return args
}
func (f *FuncUtil) getArgumentTypes(t reflect.Type) []reflect.Type {
if t.NumIn() == 0 {
return nil
}
params := []reflect.Type{}
for i := 0; i < t.NumIn(); i++ {
params = append(params, t.In(i))
}
return params
}
func getInputs(ft reflect.Type) []reflect.Type {
numIn := ft.NumIn()
inputs := make([]reflect.Type, numIn)
for i := 0; i < numIn; i++ {
inputs[i] = ft.In(i)
}
return inputs
}
func (me *MethodInvoker) decipherInputs(mt reflect.Type) {
me.inpCount = mt.NumIn() - 1 // skip the first param (me)
me.inpParams = make([]string, mt.NumIn()-1)
for i := 1; i < mt.NumIn(); i++ {
pt := mt.In(i)
me.inpParams[i-1] = getSymbolFromType(pt)
}
}
// isPubSub tests whether the given method has as as first argument a context.Context
// and returns the pair (Subscription, error)
func isPubSub(methodType reflect.Type) bool {
// numIn(0) is the receiver type
if methodType.NumIn() < 2 || methodType.NumOut() != 2 {
return false
}
return isContextType(methodType.In(1)) &&
isSubscriptionType(methodType.Out(0)) &&
isErrorType(methodType.Out(1))
}