lotus/node/config/load.go
2020-06-11 08:49:19 -07:00

58 lines
1.3 KiB
Go

package config
import (
"bytes"
"fmt"
"io"
"os"
"github.com/BurntSushi/toml"
"github.com/kelseyhightower/envconfig"
"golang.org/x/xerrors"
)
// FromFile loads config from a specified file overriding defaults specified in
// the def parameter. If file does not exist or is empty defaults are assumed.
func FromFile(path string, def interface{}) (interface{}, error) {
file, err := os.Open(path)
switch {
case os.IsNotExist(err):
return def, nil
case err != nil:
return nil, err
}
defer file.Close() //nolint:errcheck // The file is RO
return FromReader(file, def)
}
// FromReader loads config from a reader instance.
func FromReader(reader io.Reader, def interface{}) (interface{}, error) {
cfg := def
_, err := toml.DecodeReader(reader, cfg)
if err != nil {
return nil, err
}
err = envconfig.Process("LOTUS", cfg)
if err != nil {
return nil, fmt.Errorf("processing env vars overrides: %s", err)
}
return cfg, nil
}
func ConfigComment(t interface{}) ([]byte, error) {
buf := new(bytes.Buffer)
_, _ = buf.WriteString("# Default config:\n")
e := toml.NewEncoder(buf)
if err := e.Encode(t); err != nil {
return nil, xerrors.Errorf("encoding config: %w", err)
}
b := buf.Bytes()
b = bytes.ReplaceAll(b, []byte("\n"), []byte("\n#"))
b = bytes.ReplaceAll(b, []byte("#["), []byte("["))
return b, nil
}