peerpoxy intercepts and parses the raft RPCs that etcd peers use to communicate between themselves. It's designed for development and pedagogical purposes, so should not be used in production.
Though you're welcome to use the peerpoxy cmd or pkg in other ways, it comes with a pre-configured Procfile that spins up a 3 node development etcd cluster, with peerproxy pre-configured to proxy and print all messages between peers.
You'll need to install goreman to run the Procfile:
go install github.com/mattn/goreman@latest
And then you can start the cluster:
goreman start
If you want to cleanup the development data files, they're in the config directory:
rm -r config/infra*
Here's an example of the logs peerproxy outputs:
01:10:47 peerproxy | &{Upstream:localhost:32380 Path:/raft/stream/message/e46cab30ccf0234f SrcID:bdbd480b20e09794 DstID:e46cab30ccf0234f Message:type:MsgHeartbeat to:16459718964217389903 from:13672163256400123796 term:16 commit:42 snapshot:<> }
peerproxy already serves its purpose, but in the future it may support:
- Latency injection (e.g., for simulating global etcd clusters)
- Improved log messages with more metadata and less noise
- Tooling to view/filter/analyze log messages