package management import ( "context" "errors" "fmt" "io" jsoniter "github.com/json-iterator/go" "github.com/rs/zerolog" "nhooyr.io/websocket" ) var ( errInvalidMessageType = fmt.Errorf("invalid message type was provided") ) // ServerEventType represents the event types that can come from the server type ServerEventType string // ClientEventType represents the event types that can come from the client type ClientEventType string const ( UnknownClientEventType ClientEventType = "" StartStreaming ClientEventType = "start_streaming" StopStreaming ClientEventType = "stop_streaming" UnknownServerEventType ServerEventType = "" Logs ServerEventType = "logs" ) // ServerEvent is the base struct that informs, based of the Type field, which Event type was provided from the server. type ServerEvent struct { Type ServerEventType `json:"type,omitempty"` // The raw json message is provided to allow better deserialization once the type is known event jsoniter.RawMessage } // ClientEvent is the base struct that informs, based of the Type field, which Event type was provided from the client. type ClientEvent struct { Type ClientEventType `json:"type,omitempty"` // The raw json message is provided to allow better deserialization once the type is known event jsoniter.RawMessage } // EventStartStreaming signifies that the client wishes to start receiving log events. // Additional filters can be provided to augment the log events requested. type EventStartStreaming struct { ClientEvent Filters []string `json:"filters"` } // EventStopStreaming signifies that the client wishes to halt receiving log events. type EventStopStreaming struct { ClientEvent } // EventLog is the event that the server sends to the client with the log events. type EventLog struct { ServerEvent Logs []*Log `json:"logs"` } // LogEventType is the way that logging messages are able to be filtered. // Example: assigning LogEventType.Cloudflared to a zerolog event will allow the client to filter for only // the Cloudflared-related events. type LogEventType int const ( // Cloudflared events are signficant to cloudflared operations like connection state changes. // Cloudflared is also the default event type for any events that haven't been separated into a proper event type. Cloudflared LogEventType = iota HTTP TCP UDP ) func (l LogEventType) String() string { switch l { case Cloudflared: return "cloudflared" case HTTP: return "http" case TCP: return "tcp" case UDP: return "udp" default: return "" } } // LogLevel corresponds to the zerolog logging levels // "panic", "fatal", and "trace" are exempt from this list as they are rarely used and, at least // the the first two are limited to failure conditions that lead to cloudflared shutting down. type LogLevel string const ( Debug LogLevel = "debug" Info LogLevel = "info" Warn LogLevel = "warn" Error LogLevel = "error" ) const ( // TimeKey aligns with the zerolog.TimeFieldName TimeKey = "time" // LevelKey aligns with the zerolog.LevelFieldName LevelKey = "level" // LevelKey aligns with the zerolog.MessageFieldName MessageKey = "message" // EventTypeKey is the custom JSON key of the LogEventType in ZeroLogEvent EventTypeKey = "event" // FieldsKey is a custom JSON key to match and store every other key for a zerolog event FieldsKey = "fields" ) // Log is the basic structure of the events that are sent to the client. type Log struct { Time string `json:"time,omitempty"` Level LogLevel `json:"level,omitempty"` Message string `json:"message,omitempty"` Event LogEventType `json:"event,omitempty"` Fields map[string]interface{} `json:"fields,omitempty"` } // IntoClientEvent unmarshals the provided ClientEvent into the proper type. func IntoClientEvent[T EventStartStreaming | EventStopStreaming](e *ClientEvent, eventType ClientEventType) (*T, bool) { if e.Type != eventType { return nil, false } event := new(T) err := json.Unmarshal(e.event, event) if err != nil { return nil, false } return event, true } // IntoServerEvent unmarshals the provided ServerEvent into the proper type. func IntoServerEvent[T EventLog](e *ServerEvent, eventType ServerEventType) (*T, bool) { if e.Type != eventType { return nil, false } event := new(T) err := json.Unmarshal(e.event, event) if err != nil { return nil, false } return event, true } // ReadEvent will read a message from the websocket connection and parse it into a valid ServerEvent. func ReadServerEvent(c *websocket.Conn, ctx context.Context) (*ServerEvent, error) { message, err := readMessage(c, ctx) if err != nil { return nil, err } event := ServerEvent{} if err := json.Unmarshal(message, &event); err != nil { return nil, err } switch event.Type { case Logs: event.event = message return &event, nil case UnknownServerEventType: return nil, errInvalidMessageType default: return nil, fmt.Errorf("invalid server message type was provided: %s", event.Type) } } // ReadEvent will read a message from the websocket connection and parse it into a valid ClientEvent. func ReadClientEvent(c *websocket.Conn, ctx context.Context) (*ClientEvent, error) { message, err := readMessage(c, ctx) if err != nil { return nil, err } event := ClientEvent{} if err := json.Unmarshal(message, &event); err != nil { return nil, err } switch event.Type { case StartStreaming, StopStreaming: event.event = message return &event, nil case UnknownClientEventType: return nil, errInvalidMessageType default: return nil, fmt.Errorf("invalid client message type was provided: %s", event.Type) } } // readMessage will read a message from the websocket connection and return the payload. func readMessage(c *websocket.Conn, ctx context.Context) ([]byte, error) { messageType, reader, err := c.Reader(ctx) if err != nil { return nil, err } if messageType != websocket.MessageText { return nil, errInvalidMessageType } return io.ReadAll(reader) } // WriteEvent will write a Event type message to the websocket connection. func WriteEvent(c *websocket.Conn, ctx context.Context, event any) error { payload, err := json.Marshal(event) if err != nil { return err } return c.Write(ctx, websocket.MessageText, payload) } // IsClosed returns true if the websocket error is a websocket.CloseError; returns false if not a // websocket.CloseError func IsClosed(err error, log *zerolog.Logger) bool { var closeErr websocket.CloseError if errors.As(err, &closeErr) { if closeErr.Code != websocket.StatusNormalClosure { log.Debug().Msgf("connection is already closed: (%d) %s", closeErr.Code, closeErr.Reason) } return true } return false } func AsClosed(err error) *websocket.CloseError { var closeErr websocket.CloseError if errors.As(err, &closeErr) { return &closeErr } return nil }