ffhujson/ffhujson.go

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package ffhujson
import (
"bytes"
"encoding/json"
"fmt"
"io"
"github.com/tailscale/hujson"
)
// Parser is a helper function that uses a default ParseConfig.
func Parser(r io.Reader, set func(name, value string) error) error {
return (&ParseConfig{}).Parse(r, set)
}
// ParseConfig collects parameters for the config file parser.
type ParseConfig struct {
// Delimiter is used when concatenating nested node keys into a flag name.
// The default delimiter is ".".
Delimiter string
}
// Parse a document from the provided io.Reader, using the provided set
// function to set flag values. Flag names are derived from the node names and
// their key/value pairs.
func (pc *ParseConfig) Parse(r io.Reader, set func(name, value string) error) error {
if pc.Delimiter == "" {
pc.Delimiter = "."
}
data, err := io.ReadAll(r)
if err != nil {
return err
}
data, err = hujson.Standardize(data)
if err != nil {
return err
}
d := json.NewDecoder(bytes.NewBuffer(data))
d.UseNumber() // required for stringifying values
var m map[string]interface{}
if err := d.Decode(&m); err != nil {
return ParseError{Inner: err}
}
if err := traverseMap(m, pc.Delimiter, set); err != nil {
return ParseError{Inner: err}
}
return nil
}
// ParseError wraps all errors originating from the Parser.
type ParseError struct {
Inner error
}
// Error implenents the error interface.
func (e ParseError) Error() string {
return fmt.Sprintf("error parsing config: %v", e.Inner)
}
// Unwrap implements the errors.Wrapper interface, allowing errors.Is and
// errors.As to work with ParseErrors.
func (e ParseError) Unwrap() error {
return e.Inner
}