package autoconf import ( "fmt" "os" "path/filepath" "github.com/hashicorp/consul/proto/pbautoconf" "google.golang.org/protobuf/encoding/protojson" ) const ( // autoConfigFileName is the name of the file that the agent auto-config settings are // stored in within the data directory autoConfigFileName = "auto-config.json" ) var ( pbMarshaler = &protojson.MarshalOptions{ UseProtoNames: false, UseEnumNumbers: false, Indent: " ", EmitUnpopulated: true, } pbUnmarshaler = &protojson.UnmarshalOptions{ DiscardUnknown: false, } ) func (ac *AutoConfig) readPersistedAutoConfig() (*pbautoconf.AutoConfigResponse, error) { if ac.config.DataDir == "" { // no data directory means we don't have anything to potentially load return nil, nil } path := filepath.Join(ac.config.DataDir, autoConfigFileName) ac.logger.Debug("attempting to restore any persisted configuration", "path", path) content, err := os.ReadFile(path) if err == nil { var resp pbautoconf.AutoConfigResponse if err := pbUnmarshaler.Unmarshal(content, &resp); err != nil { return nil, fmt.Errorf("failed to decode persisted auto-config data: %w", err) } ac.logger.Info("read persisted configuration", "path", path) return &resp, nil } if !os.IsNotExist(err) { return nil, fmt.Errorf("failed to load %s: %w", path, err) } // ignore non-existence errors as that is an indicator that we haven't // performed the auto configuration before return nil, nil } func (ac *AutoConfig) persistAutoConfig(resp *pbautoconf.AutoConfigResponse) error { // now that we know the configuration is generally fine including TLS certs go ahead and persist it to disk. if ac.config.DataDir == "" { ac.logger.Debug("not persisting auto-config settings because there is no data directory") return nil } serialized, err := pbMarshaler.Marshal(resp) if err != nil { return fmt.Errorf("failed to encode auto-config response as JSON: %w", err) } path := filepath.Join(ac.config.DataDir, autoConfigFileName) err = os.WriteFile(path, serialized, 0660) if err != nil { return fmt.Errorf("failed to write auto-config configurations: %w", err) } ac.logger.Debug("auto-config settings were persisted to disk") return nil }