Question: Roles of nodes in memberlist

Hi @armon and @mitchellh ,

Do you think it would be possible to designate role or additional metadata regarding a node when it joins a cluster? I understand that it's currently not possible but would be interested in a PR which would allow a user to configure the role of a node and query memberlist for nodes with specific metadata?

We are currently using the name field and adding more information to the name and parse the names to decipher the roles of various nodes in a cluster.

The issue names no files, tests, or entry points. Begin by locating the node join and member representation code, then review how membership data is exposed for queries. Done would require a decided design and implementation for configurable node roles or metadata, plus coverage for joining and querying by that metadata.

Written by the indexing model from the issue text.