emqx Files

EMQ X 4.3.0 is released now, it mainly includes the following changes:

Features and Enhancement

Building

• Support Erlang/OTP 23
• The new installation package only supports macOS 10.14 and above
• Project adjusted to umbrella structure
• Support using Elixir to build plugins

Performance improvement

• The underlying implementation of the multi-language extension function is changed from erlport to gRPC
• Support routing table compression, reduce memory usage, enhance subscription performance, publishing performance will be slightly affected, so disable option is provided
• Improve wildcard subscription performance
• Improve processing performance when a large number of clients are offline

Security

• Protect EMQ X Broker from cross-site WebSocket hijacking attacks
• SSL supports verify and server_name_indication configuration
• Support the configuration of the maximum length of the certificate chain and the password of the private key file
• Use TLS v1.3 by default, TLS v1.3 configs has no effect if started on OTP 22
• JWT authentication supports JWKS

Other

• Added update resource functionality for rule engine
• Rule engine SQL function supports conversion between unix timestamp and rfc3339 format time
• Keep retrying the resources that failed to connect after the EMQ X Broker is started
• Websocket listener supports selecting supported subprotocols from the subprotocols list
• WebSocket connection supports obtaining real IP and Port
• Support the default authentication method caching_sha2_password of MySQL 8.0
• The starting point is randomly selected when the shared subscription distribution strategy is configured as round_robin
• Shared subscription supports hash distribution of messages by source topic
• Support import and export of Authentication & ACL information in Mnesia
• Allow to use base64 encoded client certificate or MD5 value of client certificate as username or Client ID
• MQTT listener restart from API/CLI
• API/CLI to force evict ACL cache
• Added observer_cli
• Support cluster metrics for Prometheus
• Redis sentinel mode supports SSL connection
• Support single-line log output, and support rfc3339 time format
• emqx_auth_clientid and emqx_auth_username are merged to emqx_auth_mnesia. Please refer to doc to export data from older versions, and import to v4.3
• By default, docker only logs to console, set EMQX_LOG__TO=file to switch to file
• Support Json format log
• Support IPv6 auto probe
• Environment variable override configuration files can be used for all distributions (previously only for docker)
• Certificate upload from dashboard has been made available for open-source edition (previously only for enterprise edition)

Bugs Fix

MQTT Protocol

• Fix the processing of MQTT heartbeat packets
• Fix MQTT packet receiving count issue
• Limit the maximum effective size of the flight window to 65535
• The value of the Keep Alive field in the Dashboard is not synchronized when Server Keep Alive was in effect

Gateway

• ACL configuration in CoAP connection does not take effect
• CoAP clients using the same ClientID can access at the same time
• The sleep mode of MQTT-SN is unavailable
• The MQTT-SN gateway will discard DISCONNECT packets in sleep mode
• The LwM2M gateway encodes and decodes numbers into unsigned integers

Resource

• The MySQL authentication SSL/TLS connection function is not available
• Fix Redis reconnection failure

Other Fixes

• ekka_locker's memory may grow infinitely under extreme conditions
• The max_inflight_size configuration item in the MQTT bridge function does not take effect
• Fix the issue of inflight in MQTT bridge
• Fixed the error of indicator statistics in the MQTT bridge function and the problem of multiple unit conversions in the retry_interval field
• Incorrect calculation of alarm duration
• The long Client ID cannot be tracked
• The query client information may crash
• The inconsistency between topic rewriting and ACL execution order when publishing and subscribing
• The WebSocket connection cannot use the peer certificate as the username
• The authentication data cannot be imported
• EMQ X may fail to start in Docker
• Fixed delayed connection process OOM kill
• The MQTT-SN connection with Clean Session being false did not publish a will message when it was disconnected abnormally