Golang mapstructure.ComposeDecodeHookFunc函數代碼示例

// DecodeConfig is a helper that handles decoding raw configuration using
// mapstructure. It returns the metadata and any errors that may happen.
// If you need extra configuration for mapstructure, you should configure
// it manually and not use this helper function.
func DecodeConfig(target interface{}, raws ...interface{}) (*mapstructure.Metadata, error) {
	decodeHook, err := decodeConfigHook(raws)
	if err != nil {
		return nil, err
	}

	var md mapstructure.Metadata
	decoderConfig := &mapstructure.DecoderConfig{
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			decodeHook,
			mapstructure.StringToSliceHookFunc(","),
		),
		Metadata:         &md,
		Result:           target,
		WeaklyTypedInput: true,
	}

	decoder, err := mapstructure.NewDecoder(decoderConfig)
	if err != nil {
		return nil, err
	}

	for _, raw := range raws {
		err := decoder.Decode(raw)
		if err != nil {
			return nil, err
		}
	}

	return &md, nil
}

// NewMapDecoder returns decoder configured for decoding data into result with all registered hooks.
func newMapDecoder(result interface{}) (*mapstructure.Decoder, error) {
	return mapstructure.NewDecoder(&mapstructure.DecoderConfig{
		DecodeHook: mapstructure.ComposeDecodeHookFunc(mapDecoderHooks...),
		Metadata:   nil,
		Result:     result,
		TagName:    TagName,
	})
}

func decodeResult(m, result interface{}) error {
	dec, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
		ZeroFields:       true,
		WeaklyTypedInput: true,
		Result:           result,
		TagName:          rreflect.TagName,
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			decodeBigIntHook,
		),
	})
	if err != nil {
		return err
	}

	return dec.Decode(m)
}

func transform(source map[string]interface{}, target interface{}) error {
	data := mapstructure.Metadata{}
	config := &mapstructure.DecoderConfig{
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			transformHook,
			mapstructure.StringToTimeDurationHookFunc()),
		Result:   target,
		Metadata: &data,
	}
	decoder, err := mapstructure.NewDecoder(config)
	if err != nil {
		return err
	}
	err = decoder.Decode(source)
	// TODO: log unused keys
	return err
}

// decodeJSON is used to decode an HTTP response body into an interface as JSON.
func decodeJSON(out interface{}, body io.ReadCloser) error {
	defer body.Close()

	var parsed interface{}
	dec := json.NewDecoder(body)
	if err := dec.Decode(&parsed); err != nil {
		return err
	}

	decoder, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			mapToHTTPHeaderHookFunc(),
			stringToTimeHookFunc(),
		),
		WeaklyTypedInput: true,
		Result:           out,
	})
	if err != nil {
		return err
	}
	return decoder.Decode(parsed)
}

// ParseConfig reads the configuration file at the given path and returns a new
// Config struct with the data populated.
func ParseConfig(path string) (*Config, error) {
	var errs *multierror.Error

	// Read the contents of the file
	contents, err := ioutil.ReadFile(path)
	if err != nil {
		return nil, fmt.Errorf("error reading config at %q: %s", path, err)
	}

	// Parse the file (could be HCL or JSON)
	var shadow interface{}
	if err := hcl.Decode(&shadow, string(contents)); err != nil {
		return nil, fmt.Errorf("error decoding config at %q: %s", path, err)
	}

	// Convert to a map and flatten the keys we want to flatten
	parsed, ok := shadow.(map[string]interface{})
	if !ok {
		return nil, fmt.Errorf("error converting config at %q", path)
	}
	flattenKeys(parsed, []string{"auth", "ssl", "syslog", "vault", "deduplicate"})

	// Create a new, empty config
	config := new(Config)

	// Use mapstructure to populate the basic config fields
	metadata := new(mapstructure.Metadata)
	decoder, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			watch.StringToWaitDurationHookFunc(),
			mapstructure.StringToSliceHookFunc(","),
			mapstructure.StringToTimeDurationHookFunc(),
		),
		ErrorUnused: true,
		Metadata:    metadata,
		Result:      config,
	})
	if err != nil {
		errs = multierror.Append(errs, err)
		return nil, errs.ErrorOrNil()
	}
	if err := decoder.Decode(parsed); err != nil {
		errs = multierror.Append(errs, err)
		return nil, errs.ErrorOrNil()
	}

	// Store a reference to the path where this config was read from
	config.Path = path

	// Ensure there's a default value for the template's file permissions
	for _, t := range config.ConfigTemplates {
		if t.Perms == 0000 {
			t.Perms = defaultFilePerms
		}
	}

	// Update the list of set keys
	if config.setKeys == nil {
		config.setKeys = make(map[string]struct{})
	}
	for _, key := range metadata.Keys {
		if _, ok := config.setKeys[key]; !ok {
			config.setKeys[key] = struct{}{}
		}
	}
	config.setKeys["path"] = struct{}{}

	d := DefaultConfig()
	d.Merge(config)
	config = d

	return config, errs.ErrorOrNil()
}

// ParseConfig reads the configuration file at the given path and returns a new
// Config struct with the data populated.
func ParseConfig(path string) (*Config, error) {
	var errs *multierror.Error

	// Read the contents of the file
	contents, err := ioutil.ReadFile(path)
	if err != nil {
		return nil, fmt.Errorf("error reading config at %q: %s", path, err)
	}

	// Parse the file (could be HCL or JSON)
	var shadow interface{}
	if err := hcl.Decode(&shadow, string(contents)); err != nil {
		return nil, fmt.Errorf("error decoding config at %q: %s", path, err)
	}

	// Convert to a map and flatten the keys we want to flatten
	parsed, ok := shadow.(map[string]interface{})
	if !ok {
		return nil, fmt.Errorf("error converting config at %q", path)
	}
	flattenKeys(parsed, []string{"auth", "ssl", "syslog"})

	// Parse the prefixes
	if raw, ok := parsed["prefixes"]; ok {
		if typed, ok := raw.([]interface{}); !ok {
			err = fmt.Errorf("error converting prefixes to []interface{} at %q, was %T", path, raw)
			errs = multierror.Append(errs, err)
			delete(parsed, "prefixes")
		} else {
			prefixes := make([]*dep.StoreKeyPrefix, 0, len(typed))
			for _, p := range typed {
				if s, ok := p.(string); ok {
					if prefix, err := dep.ParseStoreKeyPrefix(s); err != nil {
						err = fmt.Errorf("error parsing prefix %q at %q: %s", p, path, err)
						errs = multierror.Append(errs, err)
					} else {
						prefixes = append(prefixes, prefix)
					}
				} else {
					err = fmt.Errorf("error converting %T to string", p)
					errs = multierror.Append(errs, err)
					delete(parsed, "prefixes")
				}
			}
			parsed["prefixes"] = prefixes
		}
	}

	// Parse the wait component
	if raw, ok := parsed["wait"]; ok {
		if typed, ok := raw.(string); !ok {
			err = fmt.Errorf("error converting wait to string at %q", path)
			errs = multierror.Append(errs, err)
			delete(parsed, "wait")
		} else {
			if wait, err := watch.ParseWait(typed); err != nil {
				err = fmt.Errorf("error parsing wait at %q: %s", path, err)
				errs = multierror.Append(errs, err)
				delete(parsed, "wait")
			} else {
				parsed["wait"] = map[string]time.Duration{
					"min": wait.Min,
					"max": wait.Max,
				}
			}
		}
	}

	// Create a new, empty config
	config := new(Config)

	// Use mapstructure to populate the basic config fields
	metadata := new(mapstructure.Metadata)
	decoder, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			mapstructure.StringToSliceHookFunc(","),
			mapstructure.StringToTimeDurationHookFunc(),
		),
		ErrorUnused: true,
		Metadata:    metadata,
		Result:      config,
	})
	if err != nil {
		errs = multierror.Append(errs, err)
		return nil, errs.ErrorOrNil()
	}
	if err := decoder.Decode(parsed); err != nil {
		errs = multierror.Append(errs, err)
		return nil, errs.ErrorOrNil()
	}

	// Store a reference to the path where this config was read from
	config.Path = path

	// Update the list of set keys
	if config.setKeys == nil {
		config.setKeys = make(map[string]struct{})
	}
//.........這裏部分代碼省略.........

// Parse parses the given string contents as a config
func Parse(s string) (*Config, error) {
	var errs *multierror.Error

	// Parse the file (could be HCL or JSON)
	var shadow interface{}
	if err := hcl.Decode(&shadow, s); err != nil {
		return nil, fmt.Errorf("error decoding config: %s", err)
	}

	// Convert to a map and flatten the keys we want to flatten
	parsed, ok := shadow.(map[string]interface{})
	if !ok {
		return nil, fmt.Errorf("error converting config")
	}
	flattenKeys(parsed, []string{
		"auth",
		"ssl",
		"syslog",
		"exec",
		"vault",
		"deduplicate",
	})

	// Deprecations
	if vault, ok := parsed["vault"].(map[string]interface{}); ok {
		if val, ok := vault["renew"]; ok {
			log.Println(`[WARN] vault.renew has been renamed to vault.renew_token. ` +
				`Update your configuration files and change "renew" to "renew_token".`)
			vault["renew_token"] = val
			delete(vault, "renew")
		}
	}

	// Create a new, empty config
	config := new(Config)

	// Use mapstructure to populate the basic config fields
	metadata := new(mapstructure.Metadata)
	decoder, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			StringToFileModeFunc(),
			signals.StringToSignalFunc(),
			watch.StringToWaitDurationHookFunc(),
			mapstructure.StringToSliceHookFunc(","),
			mapstructure.StringToTimeDurationHookFunc(),
		),
		ErrorUnused: true,
		Metadata:    metadata,
		Result:      config,
	})
	if err != nil {
		errs = multierror.Append(errs, err)
		return nil, errs.ErrorOrNil()
	}
	if err := decoder.Decode(parsed); err != nil {
		errs = multierror.Append(errs, err)
		return nil, errs.ErrorOrNil()
	}

	// Explicitly check for the nil signal and set the value back to nil
	if config.ReloadSignal == signals.SIGNIL {
		config.ReloadSignal = nil
	}
	if config.DumpSignal == signals.SIGNIL {
		config.DumpSignal = nil
	}
	if config.KillSignal == signals.SIGNIL {
		config.KillSignal = nil
	}
	if config.Exec != nil {
		if config.Exec.ReloadSignal == signals.SIGNIL {
			config.Exec.ReloadSignal = nil
		}
		if config.Exec.KillSignal == signals.SIGNIL {
			config.Exec.KillSignal = nil
		}
	}

	// Setup default values for templates
	for _, t := range config.ConfigTemplates {
		// Ensure there's a default value for the template's file permissions
		if t.Perms == 0000 {
			t.Perms = DefaultFilePerms
		}

		// Ensure we have a default command timeout
		if t.CommandTimeout == 0 {
			t.CommandTimeout = DefaultCommandTimeout
		}

		// Set up a default zero wait, which disables it for this
		// template.
		if t.Wait == nil {
			t.Wait = &watch.Wait{}
		}
	}

	// Update the list of set keys
	if config.setKeys == nil {
//.........這裏部分代碼省略.........

// ParseConfig reads the configuration file at the given path and returns a new
// Config struct with the data populated.
func ParseConfig(path string) (*Config, error) {
	var errs *multierror.Error

	// Read the contents of the file
	contents, err := ioutil.ReadFile(path)
	if err != nil {
		return nil, fmt.Errorf("error reading config at %q: %s", path, err)
	}

	// Parse the file (could be HCL or JSON)
	var shadow interface{}
	if err := hcl.Decode(&shadow, string(contents)); err != nil {
		return nil, fmt.Errorf("error decoding config at %q: %s", path, err)
	}

	// Convert to a map and flatten the keys we want to flatten
	parsed, ok := shadow.(map[string]interface{})
	if !ok {
		return nil, fmt.Errorf("error converting config at %q", path)
	}
	flattenKeys(parsed, []string{"auth", "ssl", "syslog", "vault"})

	// Create a new, empty config
	config := new(Config)

	// Use mapstructure to populate the basic config fields
	metadata := new(mapstructure.Metadata)
	decoder, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			watch.StringToWaitDurationHookFunc(),
			mapstructure.StringToSliceHookFunc(","),
			mapstructure.StringToTimeDurationHookFunc(),
		),
		ErrorUnused: true,
		Metadata:    metadata,
		Result:      config,
	})
	if err != nil {
		errs = multierror.Append(errs, err)
		return nil, errs.ErrorOrNil()
	}
	if err := decoder.Decode(parsed); err != nil {
		errs = multierror.Append(errs, err)
		return nil, errs.ErrorOrNil()
	}

	// Store a reference to the path where this config was read from
	config.Path = path

	// Handle deprecations
	if len(config.PrefixesOld) > 0 {
		log.Printf(`[WARN] Specifying the key "prefixes" in the configuration is `+
			`no longer supported. Please specify each prefix individually using `+
			`the key "prefix" (config at %s)`, path)
		prefixes := make([]*ConfigPrefix, 0, len(config.PrefixesOld))
		for _, prefix := range config.PrefixesOld {
			prefixes = append(prefixes, &ConfigPrefix{
				Path: prefix,
			})
		}
		config.Prefixes = append(prefixes, config.Prefixes...)
		config.PrefixesOld = nil
	}

	// Update the list of set keys
	if config.setKeys == nil {
		config.setKeys = make(map[string]struct{})
	}
	for _, key := range metadata.Keys {
		if _, ok := config.setKeys[key]; !ok {
			config.setKeys[key] = struct{}{}
		}
	}
	config.setKeys["path"] = struct{}{}

	d := DefaultConfig()
	d.Merge(config)
	config = d

	return config, errs.ErrorOrNil()
}

// GetWorkUnits retrieves the keys and data dictionaries for some number
// of work units.  If options contains "work_unit_keys", those specific
// work units are retrieved; otherwise the work units are based on
// which of GetWorkUnitsOptions are present.
//
// On success, the return value is a slice of cborrpc.PythonTuple
// objects where each contains the work unit key as a byte slice and
// the data dictionary.
func (jobs *JobServer) GetWorkUnits(workSpecName string, options map[string]interface{}) ([]interface{}, string, error) {
	var workUnits map[string]coordinate.WorkUnit
	gwuOptions := GetWorkUnitsOptions{
		Limit: 1000,
	}

	spec, err := jobs.Namespace.WorkSpec(workSpecName)
	var decoder *mapstructure.Decoder
	if err == nil {
		config := mapstructure.DecoderConfig{
			DecodeHook: mapstructure.ComposeDecodeHookFunc(gwuStateHook, cborrpc.DecodeBytesAsString),
			Result:     &gwuOptions,
		}
		decoder, err = mapstructure.NewDecoder(&config)
	}
	if err == nil {
		err = decoder.Decode(options)
	}
	if err == nil {
		query := coordinate.WorkUnitQuery{
			Names: gwuOptions.WorkUnitKeys,
		}
		if gwuOptions.WorkUnitKeys == nil {
			query.PreviousName = gwuOptions.Start
			query.Limit = gwuOptions.Limit
		}
		if gwuOptions.WorkUnitKeys == nil && gwuOptions.State != nil {
			query.Statuses = make([]coordinate.WorkUnitStatus, len(gwuOptions.State))
			for i, state := range gwuOptions.State {
				query.Statuses[i], err = translateWorkUnitStatus(state)
				if err != nil {
					break
				}
			}
		}
		if err == nil {
			workUnits, err = spec.WorkUnits(query)
		}
	}
	if err != nil {
		return nil, "", err
	}
	// The marshalled result is a list of pairs of (key, data).
	var result []interface{}
	for name, unit := range workUnits {
		var data map[string]interface{}
		attempt, err := unit.ActiveAttempt()
		if err == nil && attempt != nil {
			data, err = attempt.Data()
		}
		if err == nil && data == nil {
			data, err = unit.Data()
		}
		if err != nil {
			return nil, "", err
		}
		tuple := cborrpc.PythonTuple{Items: []interface{}{[]byte(name), data}}
		result = append(result, tuple)
	}
	return result, "", nil
}

//.........這裏部分代碼省略.........
		"ssl",
		"syslog",
		"vault",
		"vault.retry",
		"vault.ssl",
		"wait",
	})

	// FlattenFlatten keys belonging to the templates. We cannot do this above
	// because it is an array of tmeplates.
	if templates, ok := parsed["template"].([]map[string]interface{}); ok {
		for _, template := range templates {
			flattenKeys(template, []string{
				"env",
				"exec",
				"exec.env",
				"wait",
			})
		}
	}

	// TODO: Deprecations
	if vault, ok := parsed["vault"].(map[string]interface{}); ok {
		if val, ok := vault["renew"]; ok {
			log.Println(`[WARN] vault.renew has been renamed to vault.renew_token. ` +
				`Update your configuration files and change "renew" to "renew_token".`)
			vault["renew_token"] = val
			delete(vault, "renew")
		}
	}

	if auth, ok := parsed["auth"].(map[string]interface{}); ok {
		log.Println("[WARN] auth has been moved under the consul stanza. " +
			"Update your configuration files and place auth inside consul { }.")
		if _, ok := parsed["consul"]; !ok {
			parsed["consul"] = make(map[string]interface{})
		}
		parsed["consul"].(map[string]interface{})["auth"] = auth
		delete(parsed, "auth")
	}

	if retry, ok := parsed["retry"].(string); ok {
		log.Println("[WARN] retry has been moved under the consul stanza. " +
			"Update your configuration files and place retry inside consul { }.")
		if _, ok := parsed["consul"]; !ok {
			parsed["consul"] = make(map[string]interface{})
		}
		parsed["consul"].(map[string]interface{})["retry"] = map[string]interface{}{
			"backoff": retry,
		}
		delete(parsed, "retry")
	}

	if ssl, ok := parsed["ssl"].(map[string]interface{}); ok {
		log.Println("[WARN] ssl has been moved under the consul stanza. " +
			"Update your configuration files and place ssl inside consul { }.")
		if _, ok := parsed["consul"]; !ok {
			parsed["consul"] = make(map[string]interface{})
		}
		parsed["consul"].(map[string]interface{})["ssl"] = ssl
		delete(parsed, "ssl")
	}

	if token, ok := parsed["token"].(string); ok {
		log.Println("[WARN] token has been moved under the consul stanza. " +
			"Update your configuration files and place token inside consul { }.")
		if _, ok := parsed["consul"]; !ok {
			parsed["consul"] = make(map[string]interface{})
		}
		parsed["consul"].(map[string]interface{})["token"] = token
		delete(parsed, "token")
	}

	// Create a new, empty config
	var c Config

	// Use mapstructure to populate the basic config fields
	var md mapstructure.Metadata
	decoder, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			ConsulStringToStructFunc(),
			StringToFileModeFunc(),
			signals.StringToSignalFunc(),
			StringToWaitDurationHookFunc(),
			mapstructure.StringToSliceHookFunc(","),
			mapstructure.StringToTimeDurationHookFunc(),
		),
		ErrorUnused: true,
		Metadata:    &md,
		Result:      &c,
	})
	if err != nil {
		return nil, errors.Wrap(err, "mapstructure decoder creation failed")
	}
	if err := decoder.Decode(parsed); err != nil {
		return nil, errors.Wrap(err, "mapstructure decode failed")
	}

	return &c, nil
}

// g reads the configuration file at the given path and returns a new
// Config struct with the data populated.
func ParseConfig(path string) (*Config, error) {
	var errs *multierror.Error

	// Read the contents of the file
	contents, err := ioutil.ReadFile(path)
	if err != nil {
		return nil, fmt.Errorf("error reading config at %q: %s", path, err)
	}

	// Parse the file (could be HCL or JSON)
	var shadow interface{}
	if err := hcl.Decode(&shadow, string(contents)); err != nil {
		return nil, fmt.Errorf("error decoding config at %q: %s", path, err)
	}

	// Convert to a map and flatten the keys we want to flatten
	parsed, ok := shadow.(map[string]interface{})
	if !ok {
		return nil, fmt.Errorf("error converting config at %q", path)
	}
	flattenKeys(parsed, []string{"auth", "ssl", "syslog"})

	// Create a new, empty config
	c := new(Config)

	// Use mapstructure to populate the basic config fields
	metadata := new(mapstructure.Metadata)
	decoder, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			config.StringToWaitDurationHookFunc(),
			mapstructure.StringToSliceHookFunc(","),
			mapstructure.StringToTimeDurationHookFunc(),
		),
		ErrorUnused: true,
		Metadata:    metadata,
		Result:      c,
	})
	if err != nil {
		errs = multierror.Append(errs, err)
		return nil, errs.ErrorOrNil()
	}
	if err := decoder.Decode(parsed); err != nil {
		errs = multierror.Append(errs, err)
		return nil, errs.ErrorOrNil()
	}

	// Store a reference to the path where this config was read from
	c.Path = path

	// Parse the prefix sources
	for _, prefix := range c.Prefixes {
		parsed, err := dep.NewKVListQuery(prefix.Source)
		if err != nil {
			errs = multierror.Append(errs, err)
			continue
		}
		prefix.Dependency = parsed

		// If no destination was given, default to the prefix
		if prefix.Destination == "" {
			prefix.Destination = prefix.Source
		}
	}

	// Update the list of set keys
	if c.setKeys == nil {
		c.setKeys = make(map[string]struct{})
	}
	for _, key := range metadata.Keys {
		if _, ok := c.setKeys[key]; !ok {
			c.setKeys[key] = struct{}{}
		}
	}
	c.setKeys["path"] = struct{}{}

	d := DefaultConfig()
	d.Merge(c)
	c = d

	return c, errs.ErrorOrNil()
}

// Decode decodes the configuration into the target and optionally
// automatically interpolates all the configuration as it goes.
func Decode(target interface{}, config *DecodeOpts, raws ...interface{}) error {
	if config == nil {
		config = &DecodeOpts{Interpolate: true}
	}

	// Interpolate first
	if config.Interpolate {
		// Detect user variables from the raws and merge them into our context
		ctx, err := DetectContext(raws...)
		if err != nil {
			return err
		}
		if config.InterpolateContext == nil {
			config.InterpolateContext = ctx
		} else {
			config.InterpolateContext.UserVariables = ctx.UserVariables
		}
		ctx = config.InterpolateContext

		// Render everything
		for i, raw := range raws {
			m, err := interpolate.RenderMap(raw, ctx, config.InterpolateFilter)
			if err != nil {
				return err
			}

			raws[i] = m
		}
	}

	// Build our decoder
	var md mapstructure.Metadata
	decoder, err := mapstructure.NewDecoder(&mapstructure.DecoderConfig{
		Result:           target,
		Metadata:         &md,
		WeaklyTypedInput: true,
		DecodeHook: mapstructure.ComposeDecodeHookFunc(
			uint8ToStringHook,
			mapstructure.StringToSliceHookFunc(","),
		),
	})
	if err != nil {
		return err
	}
	for _, raw := range raws {
		if err := decoder.Decode(raw); err != nil {
			return err
		}
	}

	// Set the metadata if it is set
	if config.Metadata != nil {
		*config.Metadata = md
	}

	// If we have unused keys, it is an error
	if len(md.Unused) > 0 {
		var err error
		sort.Strings(md.Unused)
		for _, unused := range md.Unused {
			if unused != "type" && !strings.HasPrefix(unused, "packer_") {
				err = multierror.Append(err, fmt.Errorf(
					"unknown configuration key: %q", unused))
			}
		}
		if err != nil {
			return err
		}
	}

	return nil
}