VMOD using the synchronous hiredis library API to access Redis servers from
VCL.
.
Highlights:
* Full support for execution of Lua scripts (i.e. EVAL command), including
optimistic automatic execution of EVALSHA commands.
* All Redis reply data types are supported, including partial support to
access to components of simple (i.e. not nested) array replies.
* Redis pipelines are not (and won't be) supported. Lua scripting, which is
fully supported by the VMOD, it's a much more flexible alternative to
pipelines for atomic execution and minimizing latency. Pipelines are hard
to use and error prone, specially when using the WATCH command.
* Support for classic Redis deployments using multiple replicated Redis
servers and for clustered deployments based on Redis Cluster.
* Support for multiple databases and multiple Redis connections, local to
each Varnish worker thread, or shared using one or more pools.
* Support for smart command execution, selecting the destination server
according with the preferred role (i.e. master or slave) and with distance
and healthiness metrics collected during execution.
* Support for Redis Sentinel, allowing automatic discovery of sick / healthy
servers and changes in their roles.
