cloudflare/cloudflared · error

invalid message type was provided

Error message

invalid message type was provided

What it means

Package-level sentinel error (errInvalidMessageType) in the management protocol. ReadServerEvent/ReadClientEvent return it when a decoded event's type is the zero value (UnknownServerEventType/UnknownClientEventType), meaning the peer sent a JSON message with a missing or empty 'type' field — a generic guard against malformed protocol messages.

Solutions

1. Inspect the websocket message received; its 'type' field is empty or absent.
2. Callers should compare with errors.Is(err, management.ErrInvalidMessageType) to distinguish it from typed unknown-type errors.
3. Fix the peer/sender to always set a valid event type, or ignore malformed messages in streaming loops.

When it happens

Trigger: Thrown at management/events.go:15 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of cloudflare/cloudflared@2253eeeb25 (2026-09-06). Data as JSON: /api/errors/9b932ab57709e010. Report an issue: GitHub.

Appendix: source

Thrown at management/events.go:15

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.

View on GitHub (pinned to 2253eeeb25)