// newConfigParser returns a new command line flags parser.
func newConfigParser(cfg *config, so *serviceOptions, options flags.Options) *flags.Parser {
parser := flags.NewParser(cfg, options)
if runtime.GOOS == "windows" {
parser.AddGroup("Service Options", "Service Options", so)
}
return parser
}
// loadConfig initializes and parses the config using a config file and command
// line options.
//
// The configuration proceeds as follows:
// 1) Start with a default config with sane settings
// 2) Pre-parse the command line to check for an alternative config file
// 3) Load configuration file overwriting defaults with any specified options
// 4) Parse CLI options and overwrite/add any specified options
//
// The above results in functioning properly without any config settings
// while still allowing the user to override settings with config files and
// command line options. Command line options always take precedence.
func loadConfig() (*flags.Parser, *config, []string, error) {
// Default config.
cfg := config{
ConfigFile: defaultConfigFile,
RPCServer: defaultRPCServer,
RPCCert: defaultRPCCertFile,
}
// Create the home directory if it doesn't already exist.
err := os.MkdirAll(btcdHomeDir, 0700)
if err != nil {
fmt.Fprintf(os.Stderr, "%v\n", err)
os.Exit(-1)
}
// Pre-parse the command line options to see if an alternative config
// file or the version flag was specified. Any errors can be ignored
// here since they will be caught be the final parse below.
preCfg := cfg
preParser := flags.NewParser(&preCfg, flags.None)
_, _ = preParser.Parse()
// Show the version and exit if the version flag was specified.
if preCfg.ShowVersion {
appName := filepath.Base(os.Args[0])
appName = strings.TrimSuffix(appName, filepath.Ext(appName))
fmt.Println(appName, "version", version())
os.Exit(0)
}
// Load additional config from file.
parser := flags.NewParser(&cfg, flags.PassDoubleDash|flags.HelpFlag)
err = flags.NewIniParser(parser).ParseFile(preCfg.ConfigFile)
if err != nil {
if _, ok := err.(*os.PathError); !ok {
fmt.Fprintln(os.Stderr, err)
return parser, nil, nil, err
}
}
// Parse command line options again to ensure they take precedence.
remainingArgs, err := parser.Parse()
if err != nil {
return parser, nil, nil, err
}
// Multiple networks can't be selected simultaneously.
numNets := 0
if cfg.TestNet3 {
numNets++
}
if cfg.SimNet {
numNets++
}
if numNets > 1 {
str := "%s: The testnet and simnet params can't be used " +
"together -- choose one of the two"
err := fmt.Errorf(str, "loadConfig")
fmt.Fprintln(os.Stderr, err)
return parser, nil, nil, err
}
// Override the RPC certificate if the --wallet flag was specified and
// the user did not specify one.
if cfg.Wallet && cfg.RPCCert == defaultRPCCertFile {
cfg.RPCCert = defaultWalletCertFile
}
// Handle environment variable expansion in the RPC certificate path.
cfg.RPCCert = cleanAndExpandPath(cfg.RPCCert)
// Add default port to RPC server based on --testnet and --wallet flags
// if needed.
cfg.RPCServer = normalizeAddress(cfg.RPCServer, cfg.TestNet3,
cfg.SimNet, cfg.Wallet)
return parser, &cfg, remainingArgs, nil
}