diff options
Diffstat (limited to 'vendor/github.com/mitchellh/mapstructure/mapstructure.go')
| -rw-r--r-- | vendor/github.com/mitchellh/mapstructure/mapstructure.go | 1462 |
1 files changed, 1462 insertions, 0 deletions
diff --git a/vendor/github.com/mitchellh/mapstructure/mapstructure.go b/vendor/github.com/mitchellh/mapstructure/mapstructure.go new file mode 100644 index 000000000..3643901f5 --- /dev/null +++ b/vendor/github.com/mitchellh/mapstructure/mapstructure.go @@ -0,0 +1,1462 @@ +// Package mapstructure exposes functionality to convert one arbitrary +// Go type into another, typically to convert a map[string]interface{} +// into a native Go structure. +// +// The Go structure can be arbitrarily complex, containing slices, +// other structs, etc. and the decoder will properly decode nested +// maps and so on into the proper structures in the native Go struct. +// See the examples to see what the decoder is capable of. +// +// The simplest function to start with is Decode. +// +// Field Tags +// +// When decoding to a struct, mapstructure will use the field name by +// default to perform the mapping. For example, if a struct has a field +// "Username" then mapstructure will look for a key in the source value +// of "username" (case insensitive). +// +// type User struct { +// Username string +// } +// +// You can change the behavior of mapstructure by using struct tags. +// The default struct tag that mapstructure looks for is "mapstructure" +// but you can customize it using DecoderConfig. +// +// Renaming Fields +// +// To rename the key that mapstructure looks for, use the "mapstructure" +// tag and set a value directly. For example, to change the "username" example +// above to "user": +// +// type User struct { +// Username string `mapstructure:"user"` +// } +// +// Embedded Structs and Squashing +// +// Embedded structs are treated as if they're another field with that name. +// By default, the two structs below are equivalent when decoding with +// mapstructure: +// +// type Person struct { +// Name string +// } +// +// type Friend struct { +// Person +// } +// +// type Friend struct { +// Person Person +// } +// +// This would require an input that looks like below: +// +// map[string]interface{}{ +// "person": map[string]interface{}{"name": "alice"}, +// } +// +// If your "person" value is NOT nested, then you can append ",squash" to +// your tag value and mapstructure will treat it as if the embedded struct +// were part of the struct directly. Example: +// +// type Friend struct { +// Person `mapstructure:",squash"` +// } +// +// Now the following input would be accepted: +// +// map[string]interface{}{ +// "name": "alice", +// } +// +// When decoding from a struct to a map, the squash tag squashes the struct +// fields into a single map. Using the example structs from above: +// +// Friend{Person: Person{Name: "alice"}} +// +// Will be decoded into a map: +// +// map[string]interface{}{ +// "name": "alice", +// } +// +// DecoderConfig has a field that changes the behavior of mapstructure +// to always squash embedded structs. +// +// Remainder Values +// +// If there are any unmapped keys in the source value, mapstructure by +// default will silently ignore them. You can error by setting ErrorUnused +// in DecoderConfig. If you're using Metadata you can also maintain a slice +// of the unused keys. +// +// You can also use the ",remain" suffix on your tag to collect all unused +// values in a map. The field with this tag MUST be a map type and should +// probably be a "map[string]interface{}" or "map[interface{}]interface{}". +// See example below: +// +// type Friend struct { +// Name string +// Other map[string]interface{} `mapstructure:",remain"` +// } +// +// Given the input below, Other would be populated with the other +// values that weren't used (everything but "name"): +// +// map[string]interface{}{ +// "name": "bob", +// "address": "123 Maple St.", +// } +// +// Omit Empty Values +// +// When decoding from a struct to any other value, you may use the +// ",omitempty" suffix on your tag to omit that value if it equates to +// the zero value. The zero value of all types is specified in the Go +// specification. +// +// For example, the zero type of a numeric type is zero ("0"). If the struct +// field value is zero and a numeric type, the field is empty, and it won't +// be encoded into the destination type. +// +// type Source { +// Age int `mapstructure:",omitempty"` +// } +// +// Unexported fields +// +// Since unexported (private) struct fields cannot be set outside the package +// where they are defined, the decoder will simply skip them. +// +// For this output type definition: +// +// type Exported struct { +// private string // this unexported field will be skipped +// Public string +// } +// +// Using this map as input: +// +// map[string]interface{}{ +// "private": "I will be ignored", +// "Public": "I made it through!", +// } +// +// The following struct will be decoded: +// +// type Exported struct { +// private: "" // field is left with an empty string (zero value) +// Public: "I made it through!" +// } +// +// Other Configuration +// +// mapstructure is highly configurable. See the DecoderConfig struct +// for other features and options that are supported. +package mapstructure + +import ( + "encoding/json" + "errors" + "fmt" + "reflect" + "sort" + "strconv" + "strings" +) + +// DecodeHookFunc is the callback function that can be used for +// data transformations. See "DecodeHook" in the DecoderConfig +// struct. +// +// The type must be one of DecodeHookFuncType, DecodeHookFuncKind, or +// DecodeHookFuncValue. +// Values are a superset of Types (Values can return types), and Types are a +// superset of Kinds (Types can return Kinds) and are generally a richer thing +// to use, but Kinds are simpler if you only need those. +// +// The reason DecodeHookFunc is multi-typed is for backwards compatibility: +// we started with Kinds and then realized Types were the better solution, +// but have a promise to not break backwards compat so we now support +// both. +type DecodeHookFunc interface{} + +// DecodeHookFuncType is a DecodeHookFunc which has complete information about +// the source and target types. +type DecodeHookFuncType func(reflect.Type, reflect.Type, interface{}) (interface{}, error) + +// DecodeHookFuncKind is a DecodeHookFunc which knows only the Kinds of the +// source and target types. +type DecodeHookFuncKind func(reflect.Kind, reflect.Kind, interface{}) (interface{}, error) + +// DecodeHookFuncRaw is a DecodeHookFunc which has complete access to both the source and target +// values. +type DecodeHookFuncValue func(from reflect.Value, to reflect.Value) (interface{}, error) + +// DecoderConfig is the configuration that is used to create a new decoder +// and allows customization of various aspects of decoding. +type DecoderConfig struct { + // DecodeHook, if set, will be called before any decoding and any + // type conversion (if WeaklyTypedInput is on). This lets you modify + // the values before they're set down onto the resulting struct. The + // DecodeHook is called for every map and value in the input. This means + // that if a struct has embedded fields with squash tags the decode hook + // is called only once with all of the input data, not once for each + // embedded struct. + // + // If an error is returned, the entire decode will fail with that error. + DecodeHook DecodeHookFunc + + // If ErrorUnused is true, then it is an error for there to exist + // keys in the original map that were unused in the decoding process + // (extra keys). + ErrorUnused bool + + // ZeroFields, if set to true, will zero fields before writing them. + // For example, a map will be emptied before decoded values are put in + // it. If this is false, a map will be merged. + ZeroFields bool + + // If WeaklyTypedInput is true, the decoder will make the following + // "weak" conversions: + // + // - bools to string (true = "1", false = "0") + // - numbers to string (base 10) + // - bools to int/uint (true = 1, false = 0) + // - strings to int/uint (base implied by prefix) + // - int to bool (true if value != 0) + // - string to bool (accepts: 1, t, T, TRUE, true, True, 0, f, F, + // FALSE, false, False. Anything else is an error) + // - empty array = empty map and vice versa + // - negative numbers to overflowed uint values (base 10) + // - slice of maps to a merged map + // - single values are converted to slices if required. Each + // element is weakly decoded. For example: "4" can become []int{4} + // if the target type is an int slice. + // + WeaklyTypedInput bool + + // Squash will squash embedded structs. A squash tag may also be + // added to an individual struct field using a tag. For example: + // + // type Parent struct { + // Child `mapstructure:",squash"` + // } + Squash bool + + // Metadata is the struct that will contain extra metadata about + // the decoding. If this is nil, then no metadata will be tracked. + Metadata *Metadata + + // Result is a pointer to the struct that will contain the decoded + // value. + Result interface{} + + // The tag name that mapstructure reads for field names. This + // defaults to "mapstructure" + TagName string +} + +// A Decoder takes a raw interface value and turns it into structured +// data, keeping track of rich error information along the way in case +// anything goes wrong. Unlike the basic top-level Decode method, you can +// more finely control how the Decoder behaves using the DecoderConfig +// structure. The top-level Decode method is just a convenience that sets +// up the most basic Decoder. +type Decoder struct { + config *DecoderConfig +} + +// Metadata contains information about decoding a structure that +// is tedious or difficult to get otherwise. +type Metadata struct { + // Keys are the keys of the structure which were successfully decoded + Keys []string + + // Unused is a slice of keys that were found in the raw value but + // weren't decoded since there was no matching field in the result interface + Unused []string +} + +// Decode takes an input structure and uses reflection to translate it to +// the output structure. output must be a pointer to a map or struct. +func Decode(input interface{}, output interface{}) error { + config := &DecoderConfig{ + Metadata: nil, + Result: output, + } + + decoder, err := NewDecoder(config) + if err != nil { + return err + } + + return decoder.Decode(input) +} + +// WeakDecode is the same as Decode but is shorthand to enable +// WeaklyTypedInput. See DecoderConfig for more info. +func WeakDecode(input, output interface{}) error { + config := &DecoderConfig{ + Metadata: nil, + Result: output, + WeaklyTypedInput: true, + } + + decoder, err := NewDecoder(config) + if err != nil { + return err + } + + return decoder.Decode(input) +} + +// DecodeMetadata is the same as Decode, but is shorthand to +// enable metadata collection. See DecoderConfig for more info. +func DecodeMetadata(input interface{}, output interface{}, metadata *Metadata) error { + config := &DecoderConfig{ + Metadata: metadata, + Result: output, + } + + decoder, err := NewDecoder(config) + if err != nil { + return err + } + + return decoder.Decode(input) +} + +// WeakDecodeMetadata is the same as Decode, but is shorthand to +// enable both WeaklyTypedInput and metadata collection. See +// DecoderConfig for more info. +func WeakDecodeMetadata(input interface{}, output interface{}, metadata *Metadata) error { + config := &DecoderConfig{ + Metadata: metadata, + Result: output, + WeaklyTypedInput: true, + } + + decoder, err := NewDecoder(config) + if err != nil { + return err + } + + return decoder.Decode(input) +} + +// NewDecoder returns a new decoder for the given configuration. Once +// a decoder has been returned, the same configuration must not be used +// again. +func NewDecoder(config *DecoderConfig) (*Decoder, error) { + val := reflect.ValueOf(config.Result) + if val.Kind() != reflect.Ptr { + return nil, errors.New("result must be a pointer") + } + + val = val.Elem() + if !val.CanAddr() { + return nil, errors.New("result must be addressable (a pointer)") + } + + if config.Metadata != nil { + if config.Metadata.Keys == nil { + config.Metadata.Keys = make([]string, 0) + } + + if config.Metadata.Unused == nil { + config.Metadata.Unused = make([]string, 0) + } + } + + if config.TagName == "" { + config.TagName = "mapstructure" + } + + result := &Decoder{ + config: config, + } + + return result, nil +} + +// Decode decodes the given raw interface to the target pointer specified +// by the configuration. +func (d *Decoder) Decode(input interface{}) error { + return d.decode("", input, reflect.ValueOf(d.config.Result).Elem()) +} + +// Decodes an unknown data type into a specific reflection value. +func (d *Decoder) decode(name string, input interface{}, outVal reflect.Value) error { + var inputVal reflect.Value + if input != nil { + inputVal = reflect.ValueOf(input) + + // We need to check here if input is a typed nil. Typed nils won't + // match the "input == nil" below so we check that here. + if inputVal.Kind() == reflect.Ptr && inputVal.IsNil() { + input = nil + } + } + + if input == nil { + // If the data is nil, then we don't set anything, unless ZeroFields is set + // to true. + if d.config.ZeroFields { + outVal.Set(reflect.Zero(outVal.Type())) + + if d.config.Metadata != nil && name != "" { + d.config.Metadata.Keys = append(d.config.Metadata.Keys, name) + } + } + return nil + } + + if !inputVal.IsValid() { + // If the input value is invalid, then we just set the value + // to be the zero value. + outVal.Set(reflect.Zero(outVal.Type())) + if d.config.Metadata != nil && name != "" { + d.config.Metadata.Keys = append(d.config.Metadata.Keys, name) + } + return nil + } + + if d.config.DecodeHook != nil { + // We have a DecodeHook, so let's pre-process the input. + var err error + input, err = DecodeHookExec(d.config.DecodeHook, inputVal, outVal) + if err != nil { + return fmt.Errorf("error decoding '%s': %s", name, err) + } + } + + var err error + outputKind := getKind(outVal) + addMetaKey := true + switch outputKind { + case reflect.Bool: + err = d.decodeBool(name, input, outVal) + case reflect.Interface: + err = d.decodeBasic(name, input, outVal) + case reflect.String: + err = d.decodeString(name, input, outVal) + case reflect.Int: + err = d.decodeInt(name, input, outVal) + case reflect.Uint: + err = d.decodeUint(name, input, outVal) + case reflect.Float32: + err = d.decodeFloat(name, input, outVal) + case reflect.Struct: + err = d.decodeStruct(name, input, outVal) + case reflect.Map: + err = d.decodeMap(name, input, outVal) + case reflect.Ptr: + addMetaKey, err = d.decodePtr(name, input, outVal) + case reflect.Slice: + err = d.decodeSlice(name, input, outVal) + case reflect.Array: + err = d.decodeArray(name, input, outVal) + case reflect.Func: + err = d.decodeFunc(name, input, outVal) + default: + // If we reached this point then we weren't able to decode it + return fmt.Errorf("%s: unsupported type: %s", name, outputKind) + } + + // If we reached here, then we successfully decoded SOMETHING, so + // mark the key as used if we're tracking metainput. + if addMetaKey && d.config.Metadata != nil && name != "" { + d.config.Metadata.Keys = append(d.config.Metadata.Keys, name) + } + + return err +} + +// This decodes a basic type (bool, int, string, etc.) and sets the +// value to "data" of that type. +func (d *Decoder) decodeBasic(name string, data interface{}, val reflect.Value) error { + if val.IsValid() && val.Elem().IsValid() { + elem := val.Elem() + + // If we can't address this element, then its not writable. Instead, + // we make a copy of the value (which is a pointer and therefore + // writable), decode into that, and replace the whole value. + copied := false + if !elem.CanAddr() { + copied = true + + // Make *T + copy := reflect.New(elem.Type()) + + // *T = elem + copy.Elem().Set(elem) + + // Set elem so we decode into it + elem = copy + } + + // Decode. If we have an error then return. We also return right + // away if we're not a copy because that means we decoded directly. + if err := d.decode(name, data, elem); err != nil || !copied { + return err + } + + // If we're a copy, we need to set te final result + val.Set(elem.Elem()) + return nil + } + + dataVal := reflect.ValueOf(data) + + // If the input data is a pointer, and the assigned type is the dereference + // of that exact pointer, then indirect it so that we can assign it. + // Example: *string to string + if dataVal.Kind() == reflect.Ptr && dataVal.Type().Elem() == val.Type() { + dataVal = reflect.Indirect(dataVal) + } + + if !dataVal.IsValid() { + dataVal = reflect.Zero(val.Type()) + } + + dataValType := dataVal.Type() + if !dataValType.AssignableTo(val.Type()) { + return fmt.Errorf( + "'%s' expected type '%s', got '%s'", + name, val.Type(), dataValType) + } + + val.Set(dataVal) + return nil +} + +func (d *Decoder) decodeString(name string, data interface{}, val reflect.Value) error { + dataVal := reflect.Indirect(reflect.ValueOf(data)) + dataKind := getKind(dataVal) + + converted := true + switch { + case dataKind == reflect.String: + val.SetString(dataVal.String()) + case dataKind == reflect.Bool && d.config.WeaklyTypedInput: + if dataVal.Bool() { + val.SetString("1") + } else { + val.SetString("0") + } + case dataKind == reflect.Int && d.config.WeaklyTypedInput: + val.SetString(strconv.FormatInt(dataVal.Int(), 10)) + case dataKind == reflect.Uint && d.config.WeaklyTypedInput: + val.SetString(strconv.FormatUint(dataVal.Uint(), 10)) + case dataKind == reflect.Float32 && d.config.WeaklyTypedInput: + val.SetString(strconv.FormatFloat(dataVal.Float(), 'f', -1, 64)) + case dataKind == reflect.Slice && d.config.WeaklyTypedInput, + dataKind == reflect.Array && d.config.WeaklyTypedInput: + dataType := dataVal.Type() + elemKind := dataType.Elem().Kind() + switch elemKind { + case reflect.Uint8: + var uints []uint8 + if dataKind == reflect.Array { + uints = make([]uint8, dataVal.Len(), dataVal.Len()) + for i := range uints { + uints[i] = dataVal.Index(i).Interface().(uint8) + } + } else { + uints = dataVal.Interface().([]uint8) + } + val.SetString(string(uints)) + default: + converted = false + } + default: + converted = false + } + + if !converted { + return fmt.Errorf( + "'%s' expected type '%s', got unconvertible type '%s', value: '%v'", + name, val.Type(), dataVal.Type(), data) + } + + return nil +} + +func (d *Decoder) decodeInt(name string, data interface{}, val reflect.Value) error { + dataVal := reflect.Indirect(reflect.ValueOf(data)) + dataKind := getKind(dataVal) + dataType := dataVal.Type() + + switch { + case dataKind == reflect.Int: + val.SetInt(dataVal.Int()) + case dataKind == reflect.Uint: + val.SetInt(int64(dataVal.Uint())) + case dataKind == reflect.Float32: + val.SetInt(int64(dataVal.Float())) + case dataKind == reflect.Bool && d.config.WeaklyTypedInput: + if dataVal.Bool() { + val.SetInt(1) + } else { + val.SetInt(0) + } + case dataKind == reflect.String && d.config.WeaklyTypedInput: + str := dataVal.String() + if str == "" { + str = "0" + } + + i, err := strconv.ParseInt(str, 0, val.Type().Bits()) + if err == nil { + val.SetInt(i) + } else { + return fmt.Errorf("cannot parse '%s' as int: %s", name, err) + } + case dataType.PkgPath() == "encoding/json" && dataType.Name() == "Number": + jn := data.(json.Number) + i, err := jn.Int64() + if err != nil { + return fmt.Errorf( + "error decoding json.Number into %s: %s", name, err) + } + val.SetInt(i) + default: + return fmt.Errorf( + "'%s' expected type '%s', got unconvertible type '%s', value: '%v'", + name, val.Type(), dataVal.Type(), data) + } + + return nil +} + +func (d *Decoder) decodeUint(name string, data interface{}, val reflect.Value) error { + dataVal := reflect.Indirect(reflect.ValueOf(data)) + dataKind := getKind(dataVal) + dataType := dataVal.Type() + + switch { + case dataKind == reflect.Int: + i := dataVal.Int() + if i < 0 && !d.config.WeaklyTypedInput { + return fmt.Errorf("cannot parse '%s', %d overflows uint", + name, i) + } + val.SetUint(uint64(i)) + case dataKind == reflect.Uint: + val.SetUint(dataVal.Uint()) + case dataKind == reflect.Float32: + f := dataVal.Float() + if f < 0 && !d.config.WeaklyTypedInput { + return fmt.Errorf("cannot parse '%s', %f overflows uint", + name, f) + } + val.SetUint(uint64(f)) + case dataKind == reflect.Bool && d.config.WeaklyTypedInput: + if dataVal.Bool() { + val.SetUint(1) + } else { + val.SetUint(0) + } + case dataKind == reflect.String && d.config.WeaklyTypedInput: + str := dataVal.String() + if str == "" { + str = "0" + } + + i, err := strconv.ParseUint(str, 0, val.Type().Bits()) + if err == nil { + val.SetUint(i) + } else { + return fmt.Errorf("cannot parse '%s' as uint: %s", name, err) + } + case dataType.PkgPath() == "encoding/json" && dataType.Name() == "Number": + jn := data.(json.Number) + i, err := jn.Int64() + if err != nil { + return fmt.Errorf( + "error decoding json.Number into %s: %s", name, err) + } + if i < 0 && !d.config.WeaklyTypedInput { + return fmt.Errorf("cannot parse '%s', %d overflows uint", + name, i) + } + val.SetUint(uint64(i)) + default: + return fmt.Errorf( + "'%s' expected type '%s', got unconvertible type '%s', value: '%v'", + name, val.Type(), dataVal.Type(), data) + } + + return nil +} + +func (d *Decoder) decodeBool(name string, data interface{}, val reflect.Value) error { + dataVal := reflect.Indirect(reflect.ValueOf(data)) + dataKind := getKind(dataVal) + + switch { + case dataKind == reflect.Bool: + val.SetBool(dataVal.Bool()) + case dataKind == reflect.Int && d.config.WeaklyTypedInput: + val.SetBool(dataVal.Int() != 0) + case dataKind == reflect.Uint && d.config.WeaklyTypedInput: + val.SetBool(dataVal.Uint() != 0) + case dataKind == reflect.Float32 && d.config.WeaklyTypedInput: + val.SetBool(dataVal.Float() != 0) + case dataKind == reflect.String && d.config.WeaklyTypedInput: + b, err := strconv.ParseBool(dataVal.String()) + if err == nil { + val.SetBool(b) + } else if dataVal.String() == "" { + val.SetBool(false) + } else { + return fmt.Errorf("cannot parse '%s' as bool: %s", name, err) + } + default: + return fmt.Errorf( + "'%s' expected type '%s', got unconvertible type '%s', value: '%v'", + name, val.Type(), dataVal.Type(), data) + } + + return nil +} + +func (d *Decoder) decodeFloat(name string, data interface{}, val reflect.Value) error { + dataVal := reflect.Indirect(reflect.ValueOf(data)) + dataKind := getKind(dataVal) + dataType := dataVal.Type() + + switch { + case dataKind == reflect.Int: + val.SetFloat(float64(dataVal.Int())) + case dataKind == reflect.Uint: + val.SetFloat(float64(dataVal.Uint())) + case dataKind == reflect.Float32: + val.SetFloat(dataVal.Float()) + case dataKind == reflect.Bool && d.config.WeaklyTypedInput: + if dataVal.Bool() { + val.SetFloat(1) + } else { + val.SetFloat(0) + } + case dataKind == reflect.String && d.config.WeaklyTypedInput: + str := dataVal.String() + if str == "" { + str = "0" + } + + f, err := strconv.ParseFloat(str, val.Type().Bits()) + if err == nil { + val.SetFloat(f) + } else { + return fmt.Errorf("cannot parse '%s' as float: %s", name, err) + } + case dataType.PkgPath() == "encoding/json" && dataType.Name() == "Number": + jn := data.(json.Number) + i, err := jn.Float64() + if err != nil { + return fmt.Errorf( + "error decoding json.Number into %s: %s", name, err) + } + val.SetFloat(i) + default: + return fmt.Errorf( + "'%s' expected type '%s', got unconvertible type '%s', value: '%v'", + name, val.Type(), dataVal.Type(), data) + } + + return nil +} + +func (d *Decoder) decodeMap(name string, data interface{}, val reflect.Value) error { + valType := val.Type() + valKeyType := valType.Key() + valElemType := valType.Elem() + + // By default we overwrite keys in the current map + valMap := val + + // If the map is nil or we're purposely zeroing fields, make a new map + if valMap.IsNil() || d.config.ZeroFields { + // Make a new map to hold our result + mapType := reflect.MapOf(valKeyType, valElemType) + valMap = reflect.MakeMap(mapType) + } + + // Check input type and based on the input type jump to the proper func + dataVal := reflect.Indirect(reflect.ValueOf(data)) + switch dataVal.Kind() { + case reflect.Map: + return d.decodeMapFromMap(name, dataVal, val, valMap) + + case reflect.Struct: + return d.decodeMapFromStruct(name, dataVal, val, valMap) + + case reflect.Array, reflect.Slice: + if d.config.WeaklyTypedInput { + return d.decodeMapFromSlice(name, dataVal, val, valMap) + } + + fallthrough + + default: + return fmt.Errorf("'%s' expected a map, got '%s'", name, dataVal.Kind()) + } +} + +func (d *Decoder) decodeMapFromSlice(name string, dataVal reflect.Value, val reflect.Value, valMap reflect.Value) error { + // Special case for BC reasons (covered by tests) + if dataVal.Len() == 0 { + val.Set(valMap) + return nil + } + + for i := 0; i < dataVal.Len(); i++ { + err := d.decode( + name+"["+strconv.Itoa(i)+"]", + dataVal.Index(i).Interface(), val) + if err != nil { + return err + } + } + + return nil +} + +func (d *Decoder) decodeMapFromMap(name string, dataVal reflect.Value, val reflect.Value, valMap reflect.Value) error { + valType := val.Type() + valKeyType := valType.Key() + valElemType := valType.Elem() + + // Accumulate errors + errors := make([]string, 0) + + // If the input data is empty, then we just match what the input data is. + if dataVal.Len() == 0 { + if dataVal.IsNil() { + if !val.IsNil() { + val.Set(dataVal) + } + } else { + // Set to empty allocated value + val.Set(valMap) + } + + return nil + } + + for _, k := range dataVal.MapKeys() { + fieldName := name + "[" + k.String() + "]" + + // First decode the key into the proper type + currentKey := reflect.Indirect(reflect.New(valKeyType)) + if err := d.decode(fieldName, k.Interface(), currentKey); err != nil { + errors = appendErrors(errors, err) + continue + } + + // Next decode the data into the proper type + v := dataVal.MapIndex(k).Interface() + currentVal := reflect.Indirect(reflect.New(valElemType)) + if err := d.decode(fieldName, v, currentVal); err != nil { + errors = appendErrors(errors, err) + continue + } + + valMap.SetMapIndex(currentKey, currentVal) + } + + // Set the built up map to the value + val.Set(valMap) + + // If we had errors, return those + if len(errors) > 0 { + return &Error{errors} + } + + return nil +} + +func (d *Decoder) decodeMapFromStruct(name string, dataVal reflect.Value, val reflect.Value, valMap reflect.Value) error { + typ := dataVal.Type() + for i := 0; i < typ.NumField(); i++ { + // Get the StructField first since this is a cheap operation. If the + // field is unexported, then ignore it. + f := typ.Field(i) + if f.PkgPath != "" { + continue + } + + // Next get the actual value of this field and verify it is assignable + // to the map value. + v := dataVal.Field(i) + if !v.Type().AssignableTo(valMap.Type().Elem()) { + return fmt.Errorf("cannot assign type '%s' to map value field of type '%s'", v.Type(), valMap.Type().Elem()) + } + + tagValue := f.Tag.Get(d.config.TagName) + keyName := f.Name + + // If Squash is set in the config, we squash the field down. + squash := d.config.Squash && v.Kind() == reflect.Struct && f.Anonymous + + // Determine the name of the key in the map + if index := strings.Index(tagValue, ","); index != -1 { + if tagValue[:index] == "-" { + continue + } + // If "omitempty" is specified in the tag, it ignores empty values. + if strings.Index(tagValue[index+1:], "omitempty") != -1 && isEmptyValue(v) { + continue + } + + // If "squash" is specified in the tag, we squash the field down. + squash = !squash && strings.Index(tagValue[index+1:], "squash") != -1 + if squash { + // When squashing, the embedded type can be a pointer to a struct. + if v.Kind() == reflect.Ptr && v.Elem().Kind() == reflect.Struct { + v = v.Elem() + } + + // The final type must be a struct + if v.Kind() != reflect.Struct { + return fmt.Errorf("cannot squash non-struct type '%s'", v.Type()) + } + } + keyName = tagValue[:index] + } else if len(tagValue) > 0 { + if tagValue == "-" { + continue + } + keyName = tagValue + } + + switch v.Kind() { + // this is an embedded struct, so handle it differently + case reflect.Struct: + x := reflect.New(v.Type()) + x.Elem().Set(v) + + vType := valMap.Type() + vKeyType := vType.Key() + vElemType := vType.Elem() + mType := reflect.MapOf(vKeyType, vElemType) + vMap := reflect.MakeMap(mType) + + // Creating a pointer to a map so that other methods can completely + // overwrite the map if need be (looking at you decodeMapFromMap). The + // indirection allows the underlying map to be settable (CanSet() == true) + // where as reflect.MakeMap returns an unsettable map. + addrVal := reflect.New(vMap.Type()) + reflect.Indirect(addrVal).Set(vMap) + + err := d.decode(keyName, x.Interface(), reflect.Indirect(addrVal)) + if err != nil { + return err + } + + // the underlying map may have been completely overwritten so pull + // it indirectly out of the enclosing value. + vMap = reflect.Indirect(addrVal) + + if squash { + for _, k := range vMap.MapKeys() { + valMap.SetMapIndex(k, vMap.MapIndex(k)) + } + } else { + valMap.SetMapIndex(reflect.ValueOf(keyName), vMap) + } + + default: + valMap.SetMapIndex(reflect.ValueOf(keyName), v) + } + } + + if val.CanAddr() { + val.Set(valMap) + } + + return nil +} + +func (d *Decoder) decodePtr(name string, data interface{}, val reflect.Value) (bool, error) { + // If the input data is nil, then we want to just set the output + // pointer to be nil as well. + isNil := data == nil + if !isNil { + switch v := reflect.Indirect(reflect.ValueOf(data)); v.Kind() { + case reflect.Chan, + reflect.Func, + reflect.Interface, + reflect.Map, + reflect.Ptr, + reflect.Slice: + isNil = v.IsNil() + } + } + if isNil { + if !val.IsNil() && val.CanSet() { + nilValue := reflect.New(val.Type()).Elem() + val.Set(nilValue) + } + + return true, nil + } + + // Create an element of the concrete (non pointer) type and decode + // into that. Then set the value of the pointer to this type. + valType := val.Type() + valElemType := valType.Elem() + if val.CanSet() { + realVal := val + if realVal.IsNil() || d.config.ZeroFields { + realVal = reflect.New(valElemType) + } + + if err := d.decode(name, data, reflect.Indirect(realVal)); err != nil { + return false, err + } + + val.Set(realVal) + } else { + if err := d.decode(name, data, reflect.Indirect(val)); err != nil { + return false, err + } + } + return false, nil +} + +func (d *Decoder) decodeFunc(name string, data interface{}, val reflect.Value) error { + // Create an element of the concrete (non pointer) type and decode + // into that. Then set the value of the pointer to this type. + dataVal := reflect.Indirect(reflect.ValueOf(data)) + if val.Type() != dataVal.Type() { + return fmt.Errorf( + "'%s' expected type '%s', got unconvertible type '%s', value: '%v'", + name, val.Type(), dataVal.Type(), data) + } + val.Set(dataVal) + return nil +} + +func (d *Decoder) decodeSlice(name string, data interface{}, val reflect.Value) error { + dataVal := reflect.Indirect(reflect.ValueOf(data)) + dataValKind := dataVal.Kind() + valType := val.Type() + valElemType := valType.Elem() + sliceType := reflect.SliceOf(valElemType) + + // If we have a non array/slice type then we first attempt to convert. + if dataValKind != reflect.Array && dataValKind != reflect.Slice { + if d.config.WeaklyTypedInput { + switch { + // Slice and array we use the normal logic + case dataValKind == reflect.Slice, dataValKind == reflect.Array: + break + + // Empty maps turn into empty slices + case dataValKind == reflect.Map: + if dataVal.Len() == 0 { + val.Set(reflect.MakeSlice(sliceType, 0, 0)) + return nil + } + // Create slice of maps of other sizes + return d.decodeSlice(name, []interface{}{data}, val) + + case dataValKind == reflect.String && valElemType.Kind() == reflect.Uint8: + return d.decodeSlice(name, []byte(dataVal.String()), val) + + // All other types we try to convert to the slice type + // and "lift" it into it. i.e. a string becomes a string slice. + default: + // Just re-try this function with data as a slice. + return d.decodeSlice(name, []interface{}{data}, val) + } + } + + return fmt.Errorf( + "'%s': source data must be an array or slice, got %s", name, dataValKind) + } + + // If the input value is nil, then don't allocate since empty != nil + if dataVal.IsNil() { + return nil + } + + valSlice := val + if valSlice.IsNil() || d.config.ZeroFields { + // Make a new slice to hold our result, same size as the original data. + valSlice = reflect.MakeSlice(sliceType, dataVal.Len(), dataVal.Len()) + } + + // Accumulate any errors + errors := make([]string, 0) + + for i := 0; i < dataVal.Len(); i++ { + currentData := dataVal.Index(i).Interface() + for valSlice.Len() <= i { + valSlice = reflect.Append(valSlice, reflect.Zero(valElemType)) + } + currentField := valSlice.Index(i) + + fieldName := name + "[" + strconv.Itoa(i) + "]" + if err := d.decode(fieldName, currentData, currentField); err != nil { + errors = appendErrors(errors, err) + } + } + + // Finally, set the value to the slice we built up + val.Set(valSlice) + + // If there were errors, we return those + if len(errors) > 0 { + return &Error{errors} + } + + return nil +} + +func (d *Decoder) decodeArray(name string, data interface{}, val reflect.Value) error { + dataVal := reflect.Indirect(reflect.ValueOf(data)) + dataValKind := dataVal.Kind() + valType := val.Type() + valElemType := valType.Elem() + arrayType := reflect.ArrayOf(valType.Len(), valElemType) + + valArray := val + + if valArray.Interface() == reflect.Zero(valArray.Type()).Interface() || d.config.ZeroFields { + // Check input type + if dataValKind != reflect.Array && dataValKind != reflect.Slice { + if d.config.WeaklyTypedInput { + switch { + // Empty maps turn into empty arrays + case dataValKind == reflect.Map: + if dataVal.Len() == 0 { + val.Set(reflect.Zero(arrayType)) + return nil + } + + // All other types we try to convert to the array type + // and "lift" it into it. i.e. a string becomes a string array. + default: + // Just re-try this function with data as a slice. + return d.decodeArray(name, []interface{}{data}, val) + } + } + + return fmt.Errorf( + "'%s': source data must be an array or slice, got %s", name, dataValKind) + + } + if dataVal.Len() > arrayType.Len() { + return fmt.Errorf( + "'%s': expected source data to have length less or equal to %d, got %d", name, arrayType.Len(), dataVal.Len()) + + } + + // Make a new array to hold our result, same size as the original data. + valArray = reflect.New(arrayType).Elem() + } + + // Accumulate any errors + errors := make([]string, 0) + + for i := 0; i < dataVal.Len(); i++ { + currentData := dataVal.Index(i).Interface() + currentField := valArray.Index(i) + + fieldName := name + "[" + strconv.Itoa(i) + "]" + if err := d.decode(fieldName, currentData, currentField); err != nil { + errors = appendErrors(errors, err) + } + } + + // Finally, set the value to the array we built up + val.Set(valArray) + + // If there were errors, we return those + if len(errors) > 0 { + return &Error{errors} + } + + return nil +} + +func (d *Decoder) decodeStruct(name string, data interface{}, val reflect.Value) error { + dataVal := reflect.Indirect(reflect.ValueOf(data)) + + // If the type of the value to write to and the data match directly, + // then we just set it directly instead of recursing into the structure. + if dataVal.Type() == val.Type() { + val.Set(dataVal) + return nil + } + + dataValKind := dataVal.Kind() + switch dataValKind { + case reflect.Map: + return d.decodeStructFromMap(name, dataVal, val) + + case reflect.Struct: + // Not the most efficient way to do this but we can optimize later if + // we want to. To convert from struct to struct we go to map first + // as an intermediary. + + // Make a new map to hold our result + mapType := reflect.TypeOf((map[string]interface{})(nil)) + mval := reflect.MakeMap(mapType) + + // Creating a pointer to a map so that other methods can completely + // overwrite the map if need be (looking at you decodeMapFromMap). The + // indirection allows the underlying map to be settable (CanSet() == true) + // where as reflect.MakeMap returns an unsettable map. + addrVal := reflect.New(mval.Type()) + + reflect.Indirect(addrVal).Set(mval) + if err := d.decodeMapFromStruct(name, dataVal, reflect.Indirect(addrVal), mval); err != nil { + return err + } + + result := d.decodeStructFromMap(name, reflect.Indirect(addrVal), val) + return result + + default: + return fmt.Errorf("'%s' expected a map, got '%s'", name, dataVal.Kind()) + } +} + +func (d *Decoder) decodeStructFromMap(name string, dataVal, val reflect.Value) error { + dataValType := dataVal.Type() + if kind := dataValType.Key().Kind(); kind != reflect.String && kind != reflect.Interface { + return fmt.Errorf( + "'%s' needs a map with string keys, has '%s' keys", + name, dataValType.Key().Kind()) + } + + dataValKeys := make(map[reflect.Value]struct{}) + dataValKeysUnused := make(map[interface{}]struct{}) + for _, dataValKey := range dataVal.MapKeys() { + dataValKeys[dataValKey] = struct{}{} + dataValKeysUnused[dataValKey.Interface()] = struct{}{} + } + + errors := make([]string, 0) + + // This slice will keep track of all the structs we'll be decoding. + // There can be more than one struct if there are embedded structs + // that are squashed. + structs := make([]reflect.Value, 1, 5) + structs[0] = val + + // Compile the list of all the fields that we're going to be decoding + // from all the structs. + type field struct { + field reflect.StructField + val reflect.Value + } + + // remainField is set to a valid field set with the "remain" tag if + // we are keeping track of remaining values. + var remainField *field + + fields := []field{} + for len(structs) > 0 { + structVal := structs[0] + structs = structs[1:] + + structType := structVal.Type() + + for i := 0; i < structType.NumField(); i++ { + fieldType := structType.Field(i) + fieldVal := structVal.Field(i) + if fieldVal.Kind() == reflect.Ptr && fieldVal.Elem().Kind() == reflect.Struct { + // Handle embedded struct pointers as embedded structs. + fieldVal = fieldVal.Elem() + } + + // If "squash" is specified in the tag, we squash the field down. + squash := d.config.Squash && fieldVal.Kind() == reflect.Struct && fieldType.Anonymous + remain := false + + // We always parse the tags cause we're looking for other tags too + tagParts := strings.Split(fieldType.Tag.Get(d.config.TagName), ",") + for _, tag := range tagParts[1:] { + if tag == "squash" { + squash = true + break + } + + if tag == "remain" { + remain = true + break + } + } + + if squash { + if fieldVal.Kind() != reflect.Struct { + errors = appendErrors(errors, + fmt.Errorf("%s: unsupported type for squash: %s", fieldType.Name, fieldVal.Kind())) + } else { + structs = append(structs, fieldVal) + } + continue + } + + // Build our field + if remain { + remainField = &field{fieldType, fieldVal} + } else { + // Normal struct field, store it away + fields = append(fields, field{fieldType, fieldVal}) + } + } + } + + // for fieldType, field := range fields { + for _, f := range fields { + field, fieldValue := f.field, f.val + fieldName := field.Name + + tagValue := field.Tag.Get(d.config.TagName) + tagValue = strings.SplitN(tagValue, ",", 2)[0] + if tagValue != "" { + fieldName = tagValue + } + + rawMapKey := reflect.ValueOf(fieldName) + rawMapVal := dataVal.MapIndex(rawMapKey) + if !rawMapVal.IsValid() { + // Do a slower search by iterating over each key and + // doing case-insensitive search. + for dataValKey := range dataValKeys { + mK, ok := dataValKey.Interface().(string) + if !ok { + // Not a string key + continue + } + + if strings.EqualFold(mK, fieldName) { + rawMapKey = dataValKey + rawMapVal = dataVal.MapIndex(dataValKey) + break + } + } + + if !rawMapVal.IsValid() { + // There was no matching key in the map for the value in + // the struct. Just ignore. + continue + } + } + + if !fieldValue.IsValid() { + // This should never happen + panic("field is not valid") + } + + // If we can't set the field, then it is unexported or something, + // and we just continue onwards. + if !fieldValue.CanSet() { + continue + } + + // Delete the key we're using from the unused map so we stop tracking + delete(dataValKeysUnused, rawMapKey.Interface()) + + // If the name is empty string, then we're at the root, and we + // don't dot-join the fields. + if name != "" { + fieldName = name + "." + fieldName + } + + if err := d.decode(fieldName, rawMapVal.Interface(), fieldValue); err != nil { + errors = appendErrors(errors, err) + } + } + + // If we have a "remain"-tagged field and we have unused keys then + // we put the unused keys directly into the remain field. + if remainField != nil && len(dataValKeysUnused) > 0 { + // Build a map of only the unused values + remain := map[interface{}]interface{}{} + for key := range dataValKeysUnused { + remain[key] = dataVal.MapIndex(reflect.ValueOf(key)).Interface() + } + + // Decode it as-if we were just decoding this map onto our map. + if err := d.decodeMap(name, remain, remainField.val); err != nil { + errors = appendErrors(errors, err) + } + + // Set the map to nil so we have none so that the next check will + // not error (ErrorUnused) + dataValKeysUnused = nil + } + + if d.config.ErrorUnused && len(dataValKeysUnused) > 0 { + keys := make([]string, 0, len(dataValKeysUnused)) + for rawKey := range dataValKeysUnused { + keys = append(keys, rawKey.(string)) + } + sort.Strings(keys) + + err := fmt.Errorf("'%s' has invalid keys: %s", name, strings.Join(keys, ", ")) + errors = appendErrors(errors, err) + } + + if len(errors) > 0 { + return &Error{errors} + } + + // Add the unused keys to the list of unused keys if we're tracking metadata + if d.config.Metadata != nil { + for rawKey := range dataValKeysUnused { + key := rawKey.(string) + if name != "" { + key = name + "." + key + } + + d.config.Metadata.Unused = append(d.config.Metadata.Unused, key) + } + } + + return nil +} + +func isEmptyValue(v reflect.Value) bool { + switch getKind(v) { + case reflect.Array, reflect.Map, reflect.Slice, reflect.String: + return v.Len() == 0 + case reflect.Bool: + return !v.Bool() + case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: + return v.Int() == 0 + case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr: + return v.Uint() == 0 + case reflect.Float32, reflect.Float64: + return v.Float() == 0 + case reflect.Interface, reflect.Ptr: + return v.IsNil() + } + return false +} + +func getKind(val reflect.Value) reflect.Kind { + kind := val.Kind() + + switch { + case kind >= reflect.Int && kind <= reflect.Int64: + return reflect.Int + case kind >= reflect.Uint && kind <= reflect.Uint64: + return reflect.Uint + case kind >= reflect.Float32 && kind <= reflect.Float64: + return reflect.Float32 + default: + return kind + } +} |