diff options
Diffstat (limited to 'kube2msb/src/vendor/k8s.io/kubernetes/pkg/conversion/converter.go')
-rw-r--r-- | kube2msb/src/vendor/k8s.io/kubernetes/pkg/conversion/converter.go | 951 |
1 files changed, 0 insertions, 951 deletions
diff --git a/kube2msb/src/vendor/k8s.io/kubernetes/pkg/conversion/converter.go b/kube2msb/src/vendor/k8s.io/kubernetes/pkg/conversion/converter.go deleted file mode 100644 index 7a18d63..0000000 --- a/kube2msb/src/vendor/k8s.io/kubernetes/pkg/conversion/converter.go +++ /dev/null @@ -1,951 +0,0 @@ -/* -Copyright 2014 The Kubernetes Authors. - -Licensed under the Apache License, Version 2.0 (the "License"); -you may not use this file except in compliance with the License. -You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - -Unless required by applicable law or agreed to in writing, software -distributed under the License is distributed on an "AS IS" BASIS, -WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -See the License for the specific language governing permissions and -limitations under the License. -*/ - -package conversion - -import ( - "fmt" - "reflect" -) - -type typePair struct { - source reflect.Type - dest reflect.Type -} - -type typeNamePair struct { - fieldType reflect.Type - fieldName string -} - -// DebugLogger allows you to get debugging messages if necessary. -type DebugLogger interface { - Logf(format string, args ...interface{}) -} - -type NameFunc func(t reflect.Type) string - -var DefaultNameFunc = func(t reflect.Type) string { return t.Name() } - -type GenericConversionFunc func(a, b interface{}, scope Scope) (bool, error) - -// Converter knows how to convert one type to another. -type Converter struct { - // Map from the conversion pair to a function which can - // do the conversion. - conversionFuncs ConversionFuncs - generatedConversionFuncs ConversionFuncs - - // genericConversions are called during normal conversion to offer a "fast-path" - // that avoids all reflection. These methods are not called outside of the .Convert() - // method. - genericConversions []GenericConversionFunc - - // Set of conversions that should be treated as a no-op - ignoredConversions map[typePair]struct{} - - // This is a map from a source field type and name, to a list of destination - // field type and name. - structFieldDests map[typeNamePair][]typeNamePair - - // Allows for the opposite lookup of structFieldDests. So that SourceFromDest - // copy flag also works. So this is a map of destination field name, to potential - // source field name and type to look for. - structFieldSources map[typeNamePair][]typeNamePair - - // Map from a type to a function which applies defaults. - defaultingFuncs map[reflect.Type]reflect.Value - - // Similar to above, but function is stored as interface{}. - defaultingInterfaces map[reflect.Type]interface{} - - // Map from an input type to a function which can apply a key name mapping - inputFieldMappingFuncs map[reflect.Type]FieldMappingFunc - - // Map from an input type to a set of default conversion flags. - inputDefaultFlags map[reflect.Type]FieldMatchingFlags - - // If non-nil, will be called to print helpful debugging info. Quite verbose. - Debug DebugLogger - - // nameFunc is called to retrieve the name of a type; this name is used for the - // purpose of deciding whether two types match or not (i.e., will we attempt to - // do a conversion). The default returns the go type name. - nameFunc func(t reflect.Type) string -} - -// NewConverter creates a new Converter object. -func NewConverter(nameFn NameFunc) *Converter { - c := &Converter{ - conversionFuncs: NewConversionFuncs(), - generatedConversionFuncs: NewConversionFuncs(), - ignoredConversions: make(map[typePair]struct{}), - defaultingFuncs: make(map[reflect.Type]reflect.Value), - defaultingInterfaces: make(map[reflect.Type]interface{}), - nameFunc: nameFn, - structFieldDests: make(map[typeNamePair][]typeNamePair), - structFieldSources: make(map[typeNamePair][]typeNamePair), - - inputFieldMappingFuncs: make(map[reflect.Type]FieldMappingFunc), - inputDefaultFlags: make(map[reflect.Type]FieldMatchingFlags), - } - c.RegisterConversionFunc(Convert_Slice_byte_To_Slice_byte) - return c -} - -// AddGenericConversionFunc adds a function that accepts the ConversionFunc call pattern -// (for two conversion types) to the converter. These functions are checked first during -// a normal conversion, but are otherwise not called. Use AddConversionFuncs when registering -// typed conversions. -func (c *Converter) AddGenericConversionFunc(fn GenericConversionFunc) { - c.genericConversions = append(c.genericConversions, fn) -} - -// WithConversions returns a Converter that is a copy of c but with the additional -// fns merged on top. -func (c *Converter) WithConversions(fns ConversionFuncs) *Converter { - copied := *c - copied.conversionFuncs = c.conversionFuncs.Merge(fns) - return &copied -} - -// DefaultMeta returns the conversion FieldMappingFunc and meta for a given type. -func (c *Converter) DefaultMeta(t reflect.Type) (FieldMatchingFlags, *Meta) { - return c.inputDefaultFlags[t], &Meta{ - KeyNameMapping: c.inputFieldMappingFuncs[t], - } -} - -// Convert_Slice_byte_To_Slice_byte prevents recursing into every byte -func Convert_Slice_byte_To_Slice_byte(in *[]byte, out *[]byte, s Scope) error { - if *in == nil { - *out = nil - return nil - } - *out = make([]byte, len(*in)) - copy(*out, *in) - return nil -} - -// Scope is passed to conversion funcs to allow them to continue an ongoing conversion. -// If multiple converters exist in the system, Scope will allow you to use the correct one -// from a conversion function--that is, the one your conversion function was called by. -type Scope interface { - // Call Convert to convert sub-objects. Note that if you call it with your own exact - // parameters, you'll run out of stack space before anything useful happens. - Convert(src, dest interface{}, flags FieldMatchingFlags) error - - // DefaultConvert performs the default conversion, without calling a conversion func - // on the current stack frame. This makes it safe to call from a conversion func. - DefaultConvert(src, dest interface{}, flags FieldMatchingFlags) error - - // If registered, returns a function applying defaults for objects of a given type. - // Used for automatically generating conversion functions. - DefaultingInterface(inType reflect.Type) (interface{}, bool) - - // SrcTags and DestTags contain the struct tags that src and dest had, respectively. - // If the enclosing object was not a struct, then these will contain no tags, of course. - SrcTag() reflect.StructTag - DestTag() reflect.StructTag - - // Flags returns the flags with which the conversion was started. - Flags() FieldMatchingFlags - - // Meta returns any information originally passed to Convert. - Meta() *Meta -} - -// FieldMappingFunc can convert an input field value into different values, depending on -// the value of the source or destination struct tags. -type FieldMappingFunc func(key string, sourceTag, destTag reflect.StructTag) (source string, dest string) - -func NewConversionFuncs() ConversionFuncs { - return ConversionFuncs{fns: make(map[typePair]reflect.Value)} -} - -type ConversionFuncs struct { - fns map[typePair]reflect.Value -} - -// Add adds the provided conversion functions to the lookup table - they must have the signature -// `func(type1, type2, Scope) error`. Functions are added in the order passed and will override -// previously registered pairs. -func (c ConversionFuncs) Add(fns ...interface{}) error { - for _, fn := range fns { - fv := reflect.ValueOf(fn) - ft := fv.Type() - if err := verifyConversionFunctionSignature(ft); err != nil { - return err - } - c.fns[typePair{ft.In(0).Elem(), ft.In(1).Elem()}] = fv - } - return nil -} - -// Merge returns a new ConversionFuncs that contains all conversions from -// both other and c, with other conversions taking precedence. -func (c ConversionFuncs) Merge(other ConversionFuncs) ConversionFuncs { - merged := NewConversionFuncs() - for k, v := range c.fns { - merged.fns[k] = v - } - for k, v := range other.fns { - merged.fns[k] = v - } - return merged -} - -// Meta is supplied by Scheme, when it calls Convert. -type Meta struct { - // KeyNameMapping is an optional function which may map the listed key (field name) - // into a source and destination value. - KeyNameMapping FieldMappingFunc -} - -// scope contains information about an ongoing conversion. -type scope struct { - converter *Converter - meta *Meta - flags FieldMatchingFlags - - // srcStack & destStack are separate because they may not have a 1:1 - // relationship. - srcStack scopeStack - destStack scopeStack -} - -type scopeStackElem struct { - tag reflect.StructTag - value reflect.Value - key string -} - -type scopeStack []scopeStackElem - -func (s *scopeStack) pop() { - n := len(*s) - *s = (*s)[:n-1] -} - -func (s *scopeStack) push(e scopeStackElem) { - *s = append(*s, e) -} - -func (s *scopeStack) top() *scopeStackElem { - return &(*s)[len(*s)-1] -} - -func (s scopeStack) describe() string { - desc := "" - if len(s) > 1 { - desc = "(" + s[1].value.Type().String() + ")" - } - for i, v := range s { - if i < 2 { - // First layer on stack is not real; second is handled specially above. - continue - } - if v.key == "" { - desc += fmt.Sprintf(".%v", v.value.Type()) - } else { - desc += fmt.Sprintf(".%v", v.key) - } - } - return desc -} - -func (s *scope) DefaultingInterface(inType reflect.Type) (interface{}, bool) { - value, found := s.converter.defaultingInterfaces[inType] - return value, found -} - -// Formats src & dest as indices for printing. -func (s *scope) setIndices(src, dest int) { - s.srcStack.top().key = fmt.Sprintf("[%v]", src) - s.destStack.top().key = fmt.Sprintf("[%v]", dest) -} - -// Formats src & dest as map keys for printing. -func (s *scope) setKeys(src, dest interface{}) { - s.srcStack.top().key = fmt.Sprintf(`["%v"]`, src) - s.destStack.top().key = fmt.Sprintf(`["%v"]`, dest) -} - -// Convert continues a conversion. -func (s *scope) Convert(src, dest interface{}, flags FieldMatchingFlags) error { - return s.converter.Convert(src, dest, flags, s.meta) -} - -// DefaultConvert continues a conversion, performing a default conversion (no conversion func) -// for the current stack frame. -func (s *scope) DefaultConvert(src, dest interface{}, flags FieldMatchingFlags) error { - return s.converter.DefaultConvert(src, dest, flags, s.meta) -} - -// SrcTag returns the tag of the struct containing the current source item, if any. -func (s *scope) SrcTag() reflect.StructTag { - return s.srcStack.top().tag -} - -// DestTag returns the tag of the struct containing the current dest item, if any. -func (s *scope) DestTag() reflect.StructTag { - return s.destStack.top().tag -} - -// Flags returns the flags with which the current conversion was started. -func (s *scope) Flags() FieldMatchingFlags { - return s.flags -} - -// Meta returns the meta object that was originally passed to Convert. -func (s *scope) Meta() *Meta { - return s.meta -} - -// describe prints the path to get to the current (source, dest) values. -func (s *scope) describe() (src, dest string) { - return s.srcStack.describe(), s.destStack.describe() -} - -// error makes an error that includes information about where we were in the objects -// we were asked to convert. -func (s *scope) errorf(message string, args ...interface{}) error { - srcPath, destPath := s.describe() - where := fmt.Sprintf("converting %v to %v: ", srcPath, destPath) - return fmt.Errorf(where+message, args...) -} - -// Verifies whether a conversion function has a correct signature. -func verifyConversionFunctionSignature(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(0).Kind() != reflect.Ptr { - return fmt.Errorf("expected pointer arg for 'in' param 0, got: %v", ft) - } - if ft.In(1).Kind() != reflect.Ptr { - return fmt.Errorf("expected pointer arg for 'in' param 1, got: %v", ft) - } - scopeType := Scope(nil) - if e, a := reflect.TypeOf(&scopeType).Elem(), ft.In(2); e != a { - return fmt.Errorf("expected '%v' arg for 'in' param 2, got '%v' (%v)", e, a, ft) - } - 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 -} - -// RegisterConversionFunc registers a conversion func with the -// Converter. conversionFunc must take three parameters: a pointer to the input -// type, a pointer to the output type, and a conversion.Scope (which should be -// used if recursive conversion calls are desired). It must return an error. -// -// Example: -// c.RegisterConversionFunc( -// func(in *Pod, out *v1.Pod, s Scope) error { -// // conversion logic... -// return nil -// }) -func (c *Converter) RegisterConversionFunc(conversionFunc interface{}) error { - return c.conversionFuncs.Add(conversionFunc) -} - -// Similar to RegisterConversionFunc, but registers conversion function that were -// automatically generated. -func (c *Converter) RegisterGeneratedConversionFunc(conversionFunc interface{}) error { - return c.generatedConversionFuncs.Add(conversionFunc) -} - -// RegisterIgnoredConversion registers a "no-op" for conversion, where any requested -// conversion between from and to is ignored. -func (c *Converter) RegisterIgnoredConversion(from, to interface{}) error { - typeFrom := reflect.TypeOf(from) - typeTo := reflect.TypeOf(to) - if reflect.TypeOf(from).Kind() != reflect.Ptr { - return fmt.Errorf("expected pointer arg for 'from' param 0, got: %v", typeFrom) - } - if typeTo.Kind() != reflect.Ptr { - return fmt.Errorf("expected pointer arg for 'to' param 1, got: %v", typeTo) - } - c.ignoredConversions[typePair{typeFrom.Elem(), typeTo.Elem()}] = struct{}{} - return nil -} - -// IsConversionIgnored returns true if the specified objects should be dropped during -// conversion. -func (c *Converter) IsConversionIgnored(inType, outType reflect.Type) bool { - _, found := c.ignoredConversions[typePair{inType, outType}] - return found -} - -func (c *Converter) HasConversionFunc(inType, outType reflect.Type) bool { - _, found := c.conversionFuncs.fns[typePair{inType, outType}] - return found -} - -func (c *Converter) ConversionFuncValue(inType, outType reflect.Type) (reflect.Value, bool) { - value, found := c.conversionFuncs.fns[typePair{inType, outType}] - return value, found -} - -// SetStructFieldCopy registers a correspondence. Whenever a struct field is encountered -// which has a type and name matching srcFieldType and srcFieldName, it wil be copied -// into the field in the destination struct matching destFieldType & Name, if such a -// field exists. -// May be called multiple times, even for the same source field & type--all applicable -// copies will be performed. -func (c *Converter) SetStructFieldCopy(srcFieldType interface{}, srcFieldName string, destFieldType interface{}, destFieldName string) error { - st := reflect.TypeOf(srcFieldType) - dt := reflect.TypeOf(destFieldType) - srcKey := typeNamePair{st, srcFieldName} - destKey := typeNamePair{dt, destFieldName} - c.structFieldDests[srcKey] = append(c.structFieldDests[srcKey], destKey) - c.structFieldSources[destKey] = append(c.structFieldSources[destKey], srcKey) - return nil -} - -// RegisterDefaultingFunc registers a value-defaulting func with the Converter. -// defaultingFunc must take one parameters: a pointer to the input type. -// -// Example: -// c.RegisteDefaultingFunc( -// func(in *v1.Pod) { -// // defaulting logic... -// }) -func (c *Converter) RegisterDefaultingFunc(defaultingFunc interface{}) error { - fv := reflect.ValueOf(defaultingFunc) - ft := fv.Type() - if ft.Kind() != reflect.Func { - return fmt.Errorf("expected func, got: %v", ft) - } - if ft.NumIn() != 1 { - return fmt.Errorf("expected one 'in' param, got: %v", ft) - } - if ft.NumOut() != 0 { - return fmt.Errorf("expected zero 'out' params, got: %v", ft) - } - if ft.In(0).Kind() != reflect.Ptr { - return fmt.Errorf("expected pointer arg for 'in' param 0, got: %v", ft) - } - inType := ft.In(0).Elem() - c.defaultingFuncs[inType] = fv - c.defaultingInterfaces[inType] = defaultingFunc - return nil -} - -// RegisterInputDefaults registers a field name mapping function, used when converting -// from maps to structs. Inputs to the conversion methods are checked for this type and a mapping -// applied automatically if the input matches in. A set of default flags for the input conversion -// may also be provided, which will be used when no explicit flags are requested. -func (c *Converter) RegisterInputDefaults(in interface{}, fn FieldMappingFunc, defaultFlags FieldMatchingFlags) error { - fv := reflect.ValueOf(in) - ft := fv.Type() - if ft.Kind() != reflect.Ptr { - return fmt.Errorf("expected pointer 'in' argument, got: %v", ft) - } - c.inputFieldMappingFuncs[ft] = fn - c.inputDefaultFlags[ft] = defaultFlags - return nil -} - -// FieldMatchingFlags contains a list of ways in which struct fields could be -// copied. These constants may be | combined. -type FieldMatchingFlags int - -const ( - // Loop through destination fields, search for matching source - // field to copy it from. Source fields with no corresponding - // destination field will be ignored. If SourceToDest is - // specified, this flag is ignored. If neither is specified, - // or no flags are passed, this flag is the default. - DestFromSource FieldMatchingFlags = 0 - // Loop through source fields, search for matching dest field - // to copy it into. Destination fields with no corresponding - // source field will be ignored. - SourceToDest FieldMatchingFlags = 1 << iota - // Don't treat it as an error if the corresponding source or - // dest field can't be found. - IgnoreMissingFields - // Don't require type names to match. - AllowDifferentFieldTypeNames -) - -// IsSet returns true if the given flag or combination of flags is set. -func (f FieldMatchingFlags) IsSet(flag FieldMatchingFlags) bool { - if flag == DestFromSource { - // The bit logic doesn't work on the default value. - return f&SourceToDest != SourceToDest - } - return f&flag == flag -} - -// Convert will translate src to dest if it knows how. Both must be pointers. -// If no conversion func is registered and the default copying mechanism -// doesn't work on this type pair, an error will be returned. -// Read the comments on the various FieldMatchingFlags constants to understand -// what the 'flags' parameter does. -// 'meta' is given to allow you to pass information to conversion functions, -// it is not used by Convert() other than storing it in the scope. -// Not safe for objects with cyclic references! -func (c *Converter) Convert(src, dest interface{}, flags FieldMatchingFlags, meta *Meta) error { - if len(c.genericConversions) > 0 { - // TODO: avoid scope allocation - s := &scope{converter: c, flags: flags, meta: meta} - for _, fn := range c.genericConversions { - if ok, err := fn(src, dest, s); ok { - return err - } - } - } - return c.doConversion(src, dest, flags, meta, c.convert) -} - -// DefaultConvert will translate src to dest if it knows how. Both must be pointers. -// No conversion func is used. If the default copying mechanism -// doesn't work on this type pair, an error will be returned. -// Read the comments on the various FieldMatchingFlags constants to understand -// what the 'flags' parameter does. -// 'meta' is given to allow you to pass information to conversion functions, -// it is not used by DefaultConvert() other than storing it in the scope. -// Not safe for objects with cyclic references! -func (c *Converter) DefaultConvert(src, dest interface{}, flags FieldMatchingFlags, meta *Meta) error { - return c.doConversion(src, dest, flags, meta, c.defaultConvert) -} - -type conversionFunc func(sv, dv reflect.Value, scope *scope) error - -func (c *Converter) doConversion(src, dest interface{}, flags FieldMatchingFlags, meta *Meta, f conversionFunc) error { - dv, err := EnforcePtr(dest) - if err != nil { - return err - } - if !dv.CanAddr() && !dv.CanSet() { - return fmt.Errorf("can't write to dest") - } - sv, err := EnforcePtr(src) - if err != nil { - return err - } - s := &scope{ - converter: c, - flags: flags, - meta: meta, - } - // Leave something on the stack, so that calls to struct tag getters never fail. - s.srcStack.push(scopeStackElem{}) - s.destStack.push(scopeStackElem{}) - return f(sv, dv, s) -} - -// callCustom calls 'custom' with sv & dv. custom must be a conversion function. -func (c *Converter) callCustom(sv, dv, custom reflect.Value, scope *scope) error { - if !sv.CanAddr() { - sv2 := reflect.New(sv.Type()) - sv2.Elem().Set(sv) - sv = sv2 - } else { - sv = sv.Addr() - } - if !dv.CanAddr() { - if !dv.CanSet() { - return scope.errorf("can't addr or set dest.") - } - dvOrig := dv - dv := reflect.New(dvOrig.Type()) - defer func() { dvOrig.Set(dv) }() - } else { - dv = dv.Addr() - } - args := []reflect.Value{sv, dv, reflect.ValueOf(scope)} - ret := custom.Call(args)[0].Interface() - // This convolution is necessary because nil interfaces won't convert - // to errors. - if ret == nil { - return nil - } - return ret.(error) -} - -// convert recursively copies sv into dv, calling an appropriate conversion function if -// one is registered. -func (c *Converter) convert(sv, dv reflect.Value, scope *scope) error { - dt, st := dv.Type(), sv.Type() - // Apply default values. - if fv, ok := c.defaultingFuncs[st]; ok { - if c.Debug != nil { - c.Debug.Logf("Applying defaults for '%v'", st) - } - args := []reflect.Value{sv.Addr()} - fv.Call(args) - } - - pair := typePair{st, dt} - - // ignore conversions of this type - if _, ok := c.ignoredConversions[pair]; ok { - if c.Debug != nil { - c.Debug.Logf("Ignoring conversion of '%v' to '%v'", st, dt) - } - return nil - } - - // Convert sv to dv. - if fv, ok := c.conversionFuncs.fns[pair]; ok { - if c.Debug != nil { - c.Debug.Logf("Calling custom conversion of '%v' to '%v'", st, dt) - } - return c.callCustom(sv, dv, fv, scope) - } - if fv, ok := c.generatedConversionFuncs.fns[pair]; ok { - if c.Debug != nil { - c.Debug.Logf("Calling generated conversion of '%v' to '%v'", st, dt) - } - return c.callCustom(sv, dv, fv, scope) - } - - return c.defaultConvert(sv, dv, scope) -} - -// defaultConvert recursively copies sv into dv. no conversion function is called -// for the current stack frame (but conversion functions may be called for nested objects) -func (c *Converter) defaultConvert(sv, dv reflect.Value, scope *scope) error { - dt, st := dv.Type(), sv.Type() - - if !dv.CanSet() { - return scope.errorf("Cannot set dest. (Tried to deep copy something with unexported fields?)") - } - - if !scope.flags.IsSet(AllowDifferentFieldTypeNames) && c.nameFunc(dt) != c.nameFunc(st) { - return scope.errorf( - "type names don't match (%v, %v), and no conversion 'func (%v, %v) error' registered.", - c.nameFunc(st), c.nameFunc(dt), st, dt) - } - - switch st.Kind() { - case reflect.Map, reflect.Ptr, reflect.Slice, reflect.Interface, reflect.Struct: - // Don't copy these via assignment/conversion! - default: - // This should handle all simple types. - if st.AssignableTo(dt) { - dv.Set(sv) - return nil - } - if st.ConvertibleTo(dt) { - dv.Set(sv.Convert(dt)) - return nil - } - } - - if c.Debug != nil { - c.Debug.Logf("Trying to convert '%v' to '%v'", st, dt) - } - - scope.srcStack.push(scopeStackElem{value: sv}) - scope.destStack.push(scopeStackElem{value: dv}) - defer scope.srcStack.pop() - defer scope.destStack.pop() - - switch dv.Kind() { - case reflect.Struct: - return c.convertKV(toKVValue(sv), toKVValue(dv), scope) - case reflect.Slice: - if sv.IsNil() { - // Don't make a zero-length slice. - dv.Set(reflect.Zero(dt)) - return nil - } - dv.Set(reflect.MakeSlice(dt, sv.Len(), sv.Cap())) - for i := 0; i < sv.Len(); i++ { - scope.setIndices(i, i) - if err := c.convert(sv.Index(i), dv.Index(i), scope); err != nil { - return err - } - } - case reflect.Ptr: - if sv.IsNil() { - // Don't copy a nil ptr! - dv.Set(reflect.Zero(dt)) - return nil - } - dv.Set(reflect.New(dt.Elem())) - switch st.Kind() { - case reflect.Ptr, reflect.Interface: - return c.convert(sv.Elem(), dv.Elem(), scope) - default: - return c.convert(sv, dv.Elem(), scope) - } - case reflect.Map: - if sv.IsNil() { - // Don't copy a nil ptr! - dv.Set(reflect.Zero(dt)) - return nil - } - dv.Set(reflect.MakeMap(dt)) - for _, sk := range sv.MapKeys() { - dk := reflect.New(dt.Key()).Elem() - if err := c.convert(sk, dk, scope); err != nil { - return err - } - dkv := reflect.New(dt.Elem()).Elem() - scope.setKeys(sk.Interface(), dk.Interface()) - // TODO: sv.MapIndex(sk) may return a value with CanAddr() == false, - // because a map[string]struct{} does not allow a pointer reference. - // Calling a custom conversion function defined for the map value - // will panic. Example is PodInfo map[string]ContainerStatus. - if err := c.convert(sv.MapIndex(sk), dkv, scope); err != nil { - return err - } - dv.SetMapIndex(dk, dkv) - } - case reflect.Interface: - if sv.IsNil() { - // Don't copy a nil interface! - dv.Set(reflect.Zero(dt)) - return nil - } - tmpdv := reflect.New(sv.Elem().Type()).Elem() - if err := c.convert(sv.Elem(), tmpdv, scope); err != nil { - return err - } - dv.Set(reflect.ValueOf(tmpdv.Interface())) - return nil - default: - return scope.errorf("couldn't copy '%v' into '%v'; didn't understand types", st, dt) - } - return nil -} - -var stringType = reflect.TypeOf("") - -func toKVValue(v reflect.Value) kvValue { - switch v.Kind() { - case reflect.Struct: - return structAdaptor(v) - case reflect.Map: - if v.Type().Key().AssignableTo(stringType) { - return stringMapAdaptor(v) - } - } - - return nil -} - -// kvValue lets us write the same conversion logic to work with both maps -// and structs. Only maps with string keys make sense for this. -type kvValue interface { - // returns all keys, as a []string. - keys() []string - // Will just return "" for maps. - tagOf(key string) reflect.StructTag - // Will return the zero Value if the key doesn't exist. - value(key string) reflect.Value - // Maps require explicit setting-- will do nothing for structs. - // Returns false on failure. - confirmSet(key string, v reflect.Value) bool -} - -type stringMapAdaptor reflect.Value - -func (a stringMapAdaptor) len() int { - return reflect.Value(a).Len() -} - -func (a stringMapAdaptor) keys() []string { - v := reflect.Value(a) - keys := make([]string, v.Len()) - for i, v := range v.MapKeys() { - if v.IsNil() { - continue - } - switch t := v.Interface().(type) { - case string: - keys[i] = t - } - } - return keys -} - -func (a stringMapAdaptor) tagOf(key string) reflect.StructTag { - return "" -} - -func (a stringMapAdaptor) value(key string) reflect.Value { - return reflect.Value(a).MapIndex(reflect.ValueOf(key)) -} - -func (a stringMapAdaptor) confirmSet(key string, v reflect.Value) bool { - return true -} - -type structAdaptor reflect.Value - -func (a structAdaptor) len() int { - v := reflect.Value(a) - return v.Type().NumField() -} - -func (a structAdaptor) keys() []string { - v := reflect.Value(a) - t := v.Type() - keys := make([]string, t.NumField()) - for i := range keys { - keys[i] = t.Field(i).Name - } - return keys -} - -func (a structAdaptor) tagOf(key string) reflect.StructTag { - v := reflect.Value(a) - field, ok := v.Type().FieldByName(key) - if ok { - return field.Tag - } - return "" -} - -func (a structAdaptor) value(key string) reflect.Value { - v := reflect.Value(a) - return v.FieldByName(key) -} - -func (a structAdaptor) confirmSet(key string, v reflect.Value) bool { - return true -} - -// convertKV can convert things that consist of key/value pairs, like structs -// and some maps. -func (c *Converter) convertKV(skv, dkv kvValue, scope *scope) error { - if skv == nil || dkv == nil { - // TODO: add keys to stack to support really understandable error messages. - return fmt.Errorf("Unable to convert %#v to %#v", skv, dkv) - } - - lister := dkv - if scope.flags.IsSet(SourceToDest) { - lister = skv - } - - var mapping FieldMappingFunc - if scope.meta != nil && scope.meta.KeyNameMapping != nil { - mapping = scope.meta.KeyNameMapping - } - - for _, key := range lister.keys() { - if found, err := c.checkField(key, skv, dkv, scope); found { - if err != nil { - return err - } - continue - } - stag := skv.tagOf(key) - dtag := dkv.tagOf(key) - skey := key - dkey := key - if mapping != nil { - skey, dkey = scope.meta.KeyNameMapping(key, stag, dtag) - } - - df := dkv.value(dkey) - sf := skv.value(skey) - if !df.IsValid() || !sf.IsValid() { - switch { - case scope.flags.IsSet(IgnoreMissingFields): - // No error. - case scope.flags.IsSet(SourceToDest): - return scope.errorf("%v not present in dest", dkey) - default: - return scope.errorf("%v not present in src", skey) - } - continue - } - scope.srcStack.top().key = skey - scope.srcStack.top().tag = stag - scope.destStack.top().key = dkey - scope.destStack.top().tag = dtag - if err := c.convert(sf, df, scope); err != nil { - return err - } - } - return nil -} - -// checkField returns true if the field name matches any of the struct -// field copying rules. The error should be ignored if it returns false. -func (c *Converter) checkField(fieldName string, skv, dkv kvValue, scope *scope) (bool, error) { - replacementMade := false - if scope.flags.IsSet(DestFromSource) { - df := dkv.value(fieldName) - if !df.IsValid() { - return false, nil - } - destKey := typeNamePair{df.Type(), fieldName} - // Check each of the potential source (type, name) pairs to see if they're - // present in sv. - for _, potentialSourceKey := range c.structFieldSources[destKey] { - sf := skv.value(potentialSourceKey.fieldName) - if !sf.IsValid() { - continue - } - if sf.Type() == potentialSourceKey.fieldType { - // Both the source's name and type matched, so copy. - scope.srcStack.top().key = potentialSourceKey.fieldName - scope.destStack.top().key = fieldName - if err := c.convert(sf, df, scope); err != nil { - return true, err - } - dkv.confirmSet(fieldName, df) - replacementMade = true - } - } - return replacementMade, nil - } - - sf := skv.value(fieldName) - if !sf.IsValid() { - return false, nil - } - srcKey := typeNamePair{sf.Type(), fieldName} - // Check each of the potential dest (type, name) pairs to see if they're - // present in dv. - for _, potentialDestKey := range c.structFieldDests[srcKey] { - df := dkv.value(potentialDestKey.fieldName) - if !df.IsValid() { - continue - } - if df.Type() == potentialDestKey.fieldType { - // Both the dest's name and type matched, so copy. - scope.srcStack.top().key = fieldName - scope.destStack.top().key = potentialDestKey.fieldName - if err := c.convert(sf, df, scope); err != nil { - return true, err - } - dkv.confirmSet(potentialDestKey.fieldName, df) - replacementMade = true - } - } - return replacementMade, nil -} |