This application monitor a PostgreSQL server status and updates consul as/if needed, assigning tags application can use to connect to a master/slave server without the need of a proxy, completely independent from the mechanism used to managed the actual failover/switchover for the cluster.
It will not deregister the service created, ever, since doing that would be an availability risk.
Building requires dep to be installed and in $PATH.
$ dep ensure
$ go build
Alternatively, a Dockerfile is provided to build a scratch image with the binary (requires docker CE 17.06+, since I'm using multi-stage builds).
$ docker build -t pgsql-consul:latest .
% pgsql-consul --help
Usage of pgsql-consul:
--check-interval duration Interval between checks to PostgreSQL (default 10s)
--cluster string Name of the PostgreSQL cluster (default "main")
--consul string Consul API endpoint (default "127.0.0.1:8500")
--consul-resync duration Frequency at which consul is resynchronized if no updates are detected (default 30s)
--db string PostgreSQL database connection string (default "user=postgres dbname=postgres")
--debug Enable verbose logging
- add more command line parameters (service name, consul check interval...)
- get command line parameters from environment variables