centrifugal/centrifugo v6.3.0

on GitHub

Centrifugo is an open-source scalable real-time messaging server. Centrifugo can instantly deliver messages to application online users connected over supported transports (WebSocket, HTTP-streaming, Server-Sent Events (SSE/EventSource), GRPC, WebTransport). Centrifugo has the concept of a channel – so it's a user-facing PUB/SUB server.

Centrifugo is language-agnostic and can be used to build chat apps, live comments, multiplayer games, real-time data visualizations, collaborative tools, etc. in combination with any backend. It is well suited for modern architectures and allows decoupling the business logic from the real-time transport layer.

Several official client SDKs for browser and mobile development wrap the bidirectional protocol. In addition, Centrifugo supports a unidirectional approach for simple use cases with no SDK dependency.

For details, go to the Centrifugo documentation site.

What's changed

See the Fixes section for a breaking change in this release (flags vs env priority).

Improvements

• WebSocket frame ping-pong now inherits values from client.ping_interval and client.pong_timeout #1033. This applies to both bidirectional and unidirectional WebSocket transports.
• Support for cf_connect in unidirectional WebSocket, similar to what Centrifugo provides for unidirectional SSE #1033. This allows connecting to the unidirectional WebSocket endpoint without requiring the client to send the first connect message to the server. See the updated docs.
• Slightly faster unidirectional WebSocket connection establishment due to reduced allocations #1033.
• Extrapolate custom environment variables in MapStringString config fields #1034. This helps define secret map values in config via separate environment variables. See the updated docs for environment variables.
• Centrifugo Helm chart is now published to GitHub Container Registry. See Centrifugo Packages. Contributed by @1995parham.
• Small improvement in the web UI to show milliseconds in request times sent from the Actions page.

Fixes

• Fix flags priority: flags must override environment variables #1029. This regression in Centrifugo v6 changes behavior, but it restores the documented behavior, matches previous versions, and is more natural for software. In general, this should not affect production setups, which rarely use command-line flags.
• Fix none log level by using the proper zerolog level #1027. Also warns if the configured log level is incorrect.
• Fix missing WebTransport in usage stats #1028.

Miscellaneous

• This release is built with Go 1.24.6.
• Updated dependencies.
• See also the corresponding Centrifugo PRO release.