0.4.0

Complete rewrite of the driver, to the exception of the serializers.

Breaking changes

This release is a complete breaking change with previous versions of the driver. #15

Added

• Cluster topology auto detection. contact_points are not used as the only available nodes anymore but as entry point to discover the cluster's topology.
• Cluster awareness capabilities. The driver is now capable of keeping track of which nodes are healthy or unhealthy.
• Load balancing, reconnection, retry and address resolution policies. Only one of each is currently implemented.
  • Load balancing: shared round-robin accross all workers. Used to load-balance the queries in the cluster.
  • Reconnection: shared exponential (exponential reconnection time shared accross all workers). Used to determine when an unhealthy node should be retried.
  • Retry: a basic retry policy. Used to determine which queries to retry or throw errors.
  • Address resolution: a basic address resolution policy. Used to resolve rpc_address fields.
• Waiting for schema consensus between nodes on SCHEMA_CHANGE (DML queries).
• Many more options, configurable per session/query (queries can be executed with options overriding the session's option).
• Complete abstraction of prepared queries. A simple option to execute() will handle the query preparation. If a node throws an UNPREPARED error, the query will be prepared and retried seamlessly.
• Stronger test suite. Unit/integration tests with Busted, and ngx_lua integration tests with Test::Nginx Perl module. Travis-CI jobs are also faster and more reliable, and run all test suites.
• Binary protocol auto-detection: downgrade from 3 to 2 automatically when using C* 2.0.
• Compatible with Lua 5.1, 5.2, 5.3, LuaJIT.
• Overall, a better architecture for a better maintainability.

Unchanged

• Still optimized for ngx_lua (cosocket API) and plain Lua (with LuaSocket).
• TLS client-to-node encryption and Authentication (PasswordAuthenticator) are still supported.
• The serializers stayed the same (even if their architecture was rewritten).

Removed

• No more support for query tracing (will be added back later).