62 lines
1.6 KiB
Go
62 lines
1.6 KiB
Go
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package encoding
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import (
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"sync"
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)
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// Decoder decodes the contents of b into v.
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// It's primarily used for decoding contents of a file into a map[string]interface{}.
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type Decoder interface {
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Decode(b []byte, v map[string]interface{}) error
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}
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const (
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// ErrDecoderNotFound is returned when there is no decoder registered for a format.
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ErrDecoderNotFound = encodingError("decoder not found for this format")
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// ErrDecoderFormatAlreadyRegistered is returned when an decoder is already registered for a format.
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ErrDecoderFormatAlreadyRegistered = encodingError("decoder already registered for this format")
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)
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// DecoderRegistry can choose an appropriate Decoder based on the provided format.
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type DecoderRegistry struct {
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decoders map[string]Decoder
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mu sync.RWMutex
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}
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// NewDecoderRegistry returns a new, initialized DecoderRegistry.
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func NewDecoderRegistry() *DecoderRegistry {
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return &DecoderRegistry{
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decoders: make(map[string]Decoder),
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}
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}
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// RegisterDecoder registers a Decoder for a format.
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// Registering a Decoder for an already existing format is not supported.
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func (e *DecoderRegistry) RegisterDecoder(format string, enc Decoder) error {
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e.mu.Lock()
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defer e.mu.Unlock()
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if _, ok := e.decoders[format]; ok {
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return ErrDecoderFormatAlreadyRegistered
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}
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e.decoders[format] = enc
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return nil
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}
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// Decode calls the underlying Decoder based on the format.
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func (e *DecoderRegistry) Decode(format string, b []byte, v map[string]interface{}) error {
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e.mu.RLock()
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decoder, ok := e.decoders[format]
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e.mu.RUnlock()
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if !ok {
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return ErrDecoderNotFound
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}
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return decoder.Decode(b, v)
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}
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