1044 lines
29 KiB
Go
1044 lines
29 KiB
Go
// Package mapstructure exposes functionality to convert an arbitrary
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// map[string]interface{} into a native Go structure.
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//
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// The Go structure can be arbitrarily complex, containing slices,
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// other structs, etc. and the decoder will properly decode nested
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// maps and so on into the proper structures in the native Go struct.
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// See the examples to see what the decoder is capable of.
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package mapstructure
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import (
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"encoding/json"
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"errors"
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"fmt"
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"reflect"
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"sort"
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"strconv"
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"strings"
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)
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// DecodeHookFunc is the callback function that can be used for
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// data transformations. See "DecodeHook" in the DecoderConfig
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// struct.
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//
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// The type should be DecodeHookFuncType or DecodeHookFuncKind.
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// Either is accepted. Types are a superset of Kinds (Types can return
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// Kinds) and are generally a richer thing to use, but Kinds are simpler
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// if you only need those.
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//
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// The reason DecodeHookFunc is multi-typed is for backwards compatibility:
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// we started with Kinds and then realized Types were the better solution,
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// but have a promise to not break backwards compat so we now support
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// both.
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type DecodeHookFunc interface{}
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// DecodeHookFuncType is a DecodeHookFunc which has complete information about
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// the source and target types.
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type DecodeHookFuncType func(reflect.Type, reflect.Type, interface{}) (interface{}, error)
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// DecodeHookFuncKind is a DecodeHookFunc which knows only the Kinds of the
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// source and target types.
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type DecodeHookFuncKind func(reflect.Kind, reflect.Kind, interface{}) (interface{}, error)
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// DecoderConfig is the configuration that is used to create a new decoder
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// and allows customization of various aspects of decoding.
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type DecoderConfig struct {
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// DecodeHook, if set, will be called before any decoding and any
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// type conversion (if WeaklyTypedInput is on). This lets you modify
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// the values before they're set down onto the resulting struct.
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//
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// If an error is returned, the entire decode will fail with that
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// error.
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DecodeHook DecodeHookFunc
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// If ErrorUnused is true, then it is an error for there to exist
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// keys in the original map that were unused in the decoding process
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// (extra keys).
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ErrorUnused bool
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// ZeroFields, if set to true, will zero fields before writing them.
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// For example, a map will be emptied before decoded values are put in
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// it. If this is false, a map will be merged.
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ZeroFields bool
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// If WeaklyTypedInput is true, the decoder will make the following
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// "weak" conversions:
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//
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// - bools to string (true = "1", false = "0")
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// - numbers to string (base 10)
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// - bools to int/uint (true = 1, false = 0)
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// - strings to int/uint (base implied by prefix)
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// - int to bool (true if value != 0)
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// - string to bool (accepts: 1, t, T, TRUE, true, True, 0, f, F,
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// FALSE, false, False. Anything else is an error)
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// - empty array = empty map and vice versa
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// - negative numbers to overflowed uint values (base 10)
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// - slice of maps to a merged map
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// - single values are converted to slices if required. Each
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// element is weakly decoded. For example: "4" can become []int{4}
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// if the target type is an int slice.
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//
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WeaklyTypedInput bool
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// Metadata is the struct that will contain extra metadata about
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// the decoding. If this is nil, then no metadata will be tracked.
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Metadata *Metadata
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// Result is a pointer to the struct that will contain the decoded
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// value.
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Result interface{}
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// The tag name that mapstructure reads for field names. This
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// defaults to "mapstructure"
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TagName string
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}
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// A Decoder takes a raw interface value and turns it into structured
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// data, keeping track of rich error information along the way in case
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// anything goes wrong. Unlike the basic top-level Decode method, you can
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// more finely control how the Decoder behaves using the DecoderConfig
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// structure. The top-level Decode method is just a convenience that sets
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// up the most basic Decoder.
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type Decoder struct {
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config *DecoderConfig
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}
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// Metadata contains information about decoding a structure that
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// is tedious or difficult to get otherwise.
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type Metadata struct {
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// Keys are the keys of the structure which were successfully decoded
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Keys []string
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// Unused is a slice of keys that were found in the raw value but
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// weren't decoded since there was no matching field in the result interface
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Unused []string
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}
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// Decode takes an input structure and uses reflection to translate it to
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// the output structure. output must be a pointer to a map or struct.
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func Decode(input interface{}, output interface{}) error {
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config := &DecoderConfig{
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Metadata: nil,
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Result: output,
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}
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decoder, err := NewDecoder(config)
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if err != nil {
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return err
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}
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return decoder.Decode(input)
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}
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// WeakDecode is the same as Decode but is shorthand to enable
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// WeaklyTypedInput. See DecoderConfig for more info.
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func WeakDecode(input, output interface{}) error {
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config := &DecoderConfig{
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Metadata: nil,
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Result: output,
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WeaklyTypedInput: true,
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}
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decoder, err := NewDecoder(config)
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if err != nil {
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return err
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}
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return decoder.Decode(input)
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}
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// DecodeMetadata is the same as Decode, but is shorthand to
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// enable metadata collection. See DecoderConfig for more info.
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func DecodeMetadata(input interface{}, output interface{}, metadata *Metadata) error {
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config := &DecoderConfig{
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Metadata: metadata,
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Result: output,
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}
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decoder, err := NewDecoder(config)
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if err != nil {
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return err
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}
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return decoder.Decode(input)
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}
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// WeakDecodeMetadata is the same as Decode, but is shorthand to
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// enable both WeaklyTypedInput and metadata collection. See
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// DecoderConfig for more info.
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func WeakDecodeMetadata(input interface{}, output interface{}, metadata *Metadata) error {
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config := &DecoderConfig{
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Metadata: metadata,
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Result: output,
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WeaklyTypedInput: true,
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}
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decoder, err := NewDecoder(config)
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if err != nil {
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return err
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}
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return decoder.Decode(input)
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}
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// NewDecoder returns a new decoder for the given configuration. Once
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// a decoder has been returned, the same configuration must not be used
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// again.
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func NewDecoder(config *DecoderConfig) (*Decoder, error) {
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val := reflect.ValueOf(config.Result)
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if val.Kind() != reflect.Ptr {
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return nil, errors.New("result must be a pointer")
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}
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val = val.Elem()
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if !val.CanAddr() {
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return nil, errors.New("result must be addressable (a pointer)")
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}
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if config.Metadata != nil {
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if config.Metadata.Keys == nil {
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config.Metadata.Keys = make([]string, 0)
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}
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if config.Metadata.Unused == nil {
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config.Metadata.Unused = make([]string, 0)
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}
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}
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if config.TagName == "" {
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config.TagName = "mapstructure"
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}
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result := &Decoder{
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config: config,
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}
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return result, nil
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}
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// Decode decodes the given raw interface to the target pointer specified
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// by the configuration.
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func (d *Decoder) Decode(input interface{}) error {
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return d.decode("", input, reflect.ValueOf(d.config.Result).Elem())
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}
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// Decodes an unknown data type into a specific reflection value.
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func (d *Decoder) decode(name string, input interface{}, outVal reflect.Value) error {
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if input == nil {
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// If the data is nil, then we don't set anything, unless ZeroFields is set
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// to true.
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if d.config.ZeroFields {
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outVal.Set(reflect.Zero(outVal.Type()))
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if d.config.Metadata != nil && name != "" {
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d.config.Metadata.Keys = append(d.config.Metadata.Keys, name)
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}
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}
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return nil
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}
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inputVal := reflect.ValueOf(input)
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if !inputVal.IsValid() {
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// If the input value is invalid, then we just set the value
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// to be the zero value.
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outVal.Set(reflect.Zero(outVal.Type()))
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if d.config.Metadata != nil && name != "" {
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d.config.Metadata.Keys = append(d.config.Metadata.Keys, name)
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}
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return nil
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}
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if d.config.DecodeHook != nil {
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// We have a DecodeHook, so let's pre-process the input.
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var err error
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input, err = DecodeHookExec(
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d.config.DecodeHook,
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inputVal.Type(), outVal.Type(), input)
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if err != nil {
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return fmt.Errorf("error decoding '%s': %s", name, err)
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}
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}
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var err error
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inputKind := getKind(outVal)
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switch inputKind {
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case reflect.Bool:
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err = d.decodeBool(name, input, outVal)
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case reflect.Interface:
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err = d.decodeBasic(name, input, outVal)
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case reflect.String:
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err = d.decodeString(name, input, outVal)
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case reflect.Int:
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err = d.decodeInt(name, input, outVal)
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case reflect.Uint:
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err = d.decodeUint(name, input, outVal)
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case reflect.Float32:
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err = d.decodeFloat(name, input, outVal)
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case reflect.Struct:
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err = d.decodeStruct(name, input, outVal)
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case reflect.Map:
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err = d.decodeMap(name, input, outVal)
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case reflect.Ptr:
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err = d.decodePtr(name, input, outVal)
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case reflect.Slice:
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err = d.decodeSlice(name, input, outVal)
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case reflect.Array:
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err = d.decodeArray(name, input, outVal)
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case reflect.Func:
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err = d.decodeFunc(name, input, outVal)
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default:
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// If we reached this point then we weren't able to decode it
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return fmt.Errorf("%s: unsupported type: %s", name, inputKind)
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}
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// If we reached here, then we successfully decoded SOMETHING, so
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// mark the key as used if we're tracking metainput.
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if d.config.Metadata != nil && name != "" {
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d.config.Metadata.Keys = append(d.config.Metadata.Keys, name)
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}
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return err
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}
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// This decodes a basic type (bool, int, string, etc.) and sets the
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// value to "data" of that type.
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func (d *Decoder) decodeBasic(name string, data interface{}, val reflect.Value) error {
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if val.IsValid() && val.Elem().IsValid() {
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return d.decode(name, data, val.Elem())
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}
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dataVal := reflect.ValueOf(data)
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if !dataVal.IsValid() {
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dataVal = reflect.Zero(val.Type())
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}
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dataValType := dataVal.Type()
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if !dataValType.AssignableTo(val.Type()) {
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return fmt.Errorf(
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"'%s' expected type '%s', got '%s'",
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name, val.Type(), dataValType)
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}
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val.Set(dataVal)
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return nil
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}
|
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func (d *Decoder) decodeString(name string, data interface{}, val reflect.Value) error {
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dataVal := reflect.ValueOf(data)
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dataKind := getKind(dataVal)
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converted := true
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switch {
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case dataKind == reflect.String:
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val.SetString(dataVal.String())
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case dataKind == reflect.Bool && d.config.WeaklyTypedInput:
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if dataVal.Bool() {
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val.SetString("1")
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} else {
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val.SetString("0")
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}
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case dataKind == reflect.Int && d.config.WeaklyTypedInput:
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val.SetString(strconv.FormatInt(dataVal.Int(), 10))
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case dataKind == reflect.Uint && d.config.WeaklyTypedInput:
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val.SetString(strconv.FormatUint(dataVal.Uint(), 10))
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case dataKind == reflect.Float32 && d.config.WeaklyTypedInput:
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val.SetString(strconv.FormatFloat(dataVal.Float(), 'f', -1, 64))
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case dataKind == reflect.Slice && d.config.WeaklyTypedInput,
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dataKind == reflect.Array && d.config.WeaklyTypedInput:
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dataType := dataVal.Type()
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elemKind := dataType.Elem().Kind()
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switch elemKind {
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case reflect.Uint8:
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var uints []uint8
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if dataKind == reflect.Array {
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uints = make([]uint8, dataVal.Len(), dataVal.Len())
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for i := range uints {
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uints[i] = dataVal.Index(i).Interface().(uint8)
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}
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} else {
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uints = dataVal.Interface().([]uint8)
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}
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val.SetString(string(uints))
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default:
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converted = false
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}
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default:
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converted = false
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}
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|
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if !converted {
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return fmt.Errorf(
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"'%s' expected type '%s', got unconvertible type '%s'",
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name, val.Type(), dataVal.Type())
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}
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return nil
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}
|
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func (d *Decoder) decodeInt(name string, data interface{}, val reflect.Value) error {
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dataVal := reflect.ValueOf(data)
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dataKind := getKind(dataVal)
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dataType := dataVal.Type()
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switch {
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case dataKind == reflect.Int:
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val.SetInt(dataVal.Int())
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case dataKind == reflect.Uint:
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val.SetInt(int64(dataVal.Uint()))
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case dataKind == reflect.Float32:
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val.SetInt(int64(dataVal.Float()))
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case dataKind == reflect.Bool && d.config.WeaklyTypedInput:
|
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if dataVal.Bool() {
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val.SetInt(1)
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} else {
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val.SetInt(0)
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}
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case dataKind == reflect.String && d.config.WeaklyTypedInput:
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i, err := strconv.ParseInt(dataVal.String(), 0, val.Type().Bits())
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if err == nil {
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val.SetInt(i)
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} else {
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return fmt.Errorf("cannot parse '%s' as int: %s", name, err)
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}
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case dataType.PkgPath() == "encoding/json" && dataType.Name() == "Number":
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jn := data.(json.Number)
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i, err := jn.Int64()
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if err != nil {
|
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return fmt.Errorf(
|
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"error decoding json.Number into %s: %s", name, err)
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}
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val.SetInt(i)
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default:
|
|
return fmt.Errorf(
|
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"'%s' expected type '%s', got unconvertible type '%s'",
|
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name, val.Type(), dataVal.Type())
|
|
}
|
|
|
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return nil
|
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}
|
|
|
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func (d *Decoder) decodeUint(name string, data interface{}, val reflect.Value) error {
|
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dataVal := reflect.ValueOf(data)
|
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dataKind := getKind(dataVal)
|
|
|
|
switch {
|
|
case dataKind == reflect.Int:
|
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i := dataVal.Int()
|
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if i < 0 && !d.config.WeaklyTypedInput {
|
|
return fmt.Errorf("cannot parse '%s', %d overflows uint",
|
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name, i)
|
|
}
|
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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:
|
|
i, err := strconv.ParseUint(dataVal.String(), 0, val.Type().Bits())
|
|
if err == nil {
|
|
val.SetUint(i)
|
|
} else {
|
|
return fmt.Errorf("cannot parse '%s' as uint: %s", name, err)
|
|
}
|
|
default:
|
|
return fmt.Errorf(
|
|
"'%s' expected type '%s', got unconvertible type '%s'",
|
|
name, val.Type(), dataVal.Type())
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (d *Decoder) decodeBool(name string, data interface{}, val reflect.Value) error {
|
|
dataVal := 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'",
|
|
name, val.Type(), dataVal.Type())
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (d *Decoder) decodeFloat(name string, data interface{}, val reflect.Value) error {
|
|
dataVal := 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:
|
|
f, err := strconv.ParseFloat(dataVal.String(), 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'",
|
|
name, val.Type(), dataVal.Type())
|
|
}
|
|
|
|
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(
|
|
fmt.Sprintf("%s[%d]", name, 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)
|
|
|
|
for _, k := range dataVal.MapKeys() {
|
|
fieldName := fmt.Sprintf("%s[%s]", name, k)
|
|
|
|
// 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())
|
|
}
|
|
|
|
// Determine the name of the key in the map
|
|
keyName := f.Name
|
|
tagValue := f.Tag.Get(d.config.TagName)
|
|
tagValue = strings.SplitN(tagValue, ",", 2)[0]
|
|
if tagValue != "" {
|
|
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)
|
|
|
|
err := d.decode(keyName, x.Interface(), vMap)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
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) error {
|
|
// 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 err
|
|
}
|
|
|
|
val.Set(realVal)
|
|
} else {
|
|
if err := d.decode(name, data, reflect.Indirect(val)); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
return 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'",
|
|
name, val.Type(), dataVal.Type())
|
|
}
|
|
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)
|
|
|
|
valSlice := val
|
|
if valSlice.IsNil() || d.config.ZeroFields {
|
|
// Check input type
|
|
if dataValKind != reflect.Array && dataValKind != reflect.Slice {
|
|
if d.config.WeaklyTypedInput {
|
|
switch {
|
|
// Empty maps turn into empty slices
|
|
case dataValKind == reflect.Map:
|
|
if dataVal.Len() == 0 {
|
|
val.Set(reflect.MakeSlice(sliceType, 0, 0))
|
|
return nil
|
|
}
|
|
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)
|
|
|
|
}
|
|
|
|
// 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 := fmt.Sprintf("%s[%d]", name, 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 := fmt.Sprintf("%s[%d]", name, 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()
|
|
if dataValKind != reflect.Map {
|
|
return fmt.Errorf("'%s' expected a map, got '%s'", name, dataValKind)
|
|
}
|
|
|
|
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
|
|
}
|
|
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)
|
|
fieldKind := fieldType.Type.Kind()
|
|
|
|
// If "squash" is specified in the tag, we squash the field down.
|
|
squash := false
|
|
tagParts := strings.Split(fieldType.Tag.Get(d.config.TagName), ",")
|
|
for _, tag := range tagParts[1:] {
|
|
if tag == "squash" {
|
|
squash = true
|
|
break
|
|
}
|
|
}
|
|
|
|
if squash {
|
|
if fieldKind != reflect.Struct {
|
|
errors = appendErrors(errors,
|
|
fmt.Errorf("%s: unsupported type for squash: %s", fieldType.Name, fieldKind))
|
|
} else {
|
|
structs = append(structs, structVal.FieldByName(fieldType.Name))
|
|
}
|
|
continue
|
|
}
|
|
|
|
// Normal struct field, store it away
|
|
fields = append(fields, field{fieldType, structVal.Field(i)})
|
|
}
|
|
}
|
|
|
|
// 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
|
|
}
|
|
}
|
|
|
|
// Delete the key we're using from the unused map so we stop tracking
|
|
delete(dataValKeysUnused, rawMapKey.Interface())
|
|
|
|
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
|
|
}
|
|
|
|
// If the name is empty string, then we're at the root, and we
|
|
// don't dot-join the fields.
|
|
if name != "" {
|
|
fieldName = fmt.Sprintf("%s.%s", name, fieldName)
|
|
}
|
|
|
|
if err := d.decode(fieldName, rawMapVal.Interface(), fieldValue); err != nil {
|
|
errors = appendErrors(errors, err)
|
|
}
|
|
}
|
|
|
|
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 = fmt.Sprintf("%s.%s", name, key)
|
|
}
|
|
|
|
d.config.Metadata.Unused = append(d.config.Metadata.Unused, key)
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
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
|
|
}
|
|
}
|