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 }