display messages from serf in cli

[hanshasselberg]

This PR shows the messages from serf when listing encryption keys. Needs hashicorp/serf#546.

[banks]

Awesome! An example of what this looks like in practice in the PR description would be extra useful but this seems reasonable!

[hanshasselberg]

In case of too many keys it looks like that with 3 servers and 20 clients:

$ consul keyring -list
==> Gathering installed encryption keys...

WAN:
  ===> l.dc1: truncated key list response, showing first 35 of 51 keys
  ===> s1.dc1: truncated key list response, showing first 35 of 51 keys
  ===> s2.dc1: truncated key list response, showing first 35 of 51 keys
  OvEV7rcTLSapFpKiG0jjGw== [3/3]
  1Ty40u6Dk8TfS/d9tgKjsQ== [3/3]
  9f4Y+1AbSh2UxkYO6LyYGw== [3/3]
  9kZ2mJ94E9mFnM9DyQsGAA== [3/3]
  AEQVHZOXCYAHuqBqx8kb1Q== [3/3]
  nPhbUOxxfVO0waK/Q4/lhg== [3/3]
  /B7pNWgPFYl7USV+WPLqAA== [3/3]
  J+It1aLhS1Lv8kJMEh7Z3g== [3/3]
  SrMp0SvH/At/s8kpSs5nKw== [3/3]
  mdQsc9vIOxwNOjyk4Pgo5g== [3/3]
  tL6kLg1kZW/ry5Gk8njR9g== [3/3]
  vA7+zGspI45mW+bZHXbyRQ== [3/3]
  34jTVOtF/Qw2/TrATsIiIw== [3/3]
  Tq416DQdzmPCSTAyGSlLHA== [3/3]
  Um7HOKl7x0hdfR0crjPY/A== [3/3]
  d0w0FM3LvmSArte2mS9Y3w== [3/3]
  jNlaF7ahFUxhEGYIzH6pxA== [3/3]
  keGbbBa2y8eGvTOxyOhwQw== [3/3]
  kgX+E0XmXYefBxwAuNY9Lw== [3/3]
  uGEHpx1Uy/rLEy5x5vpYew== [3/3]
  N4J2duCWwwY7/QikpqtqRg== [3/3]
  XgVr0n8l3qWwI66keY5cmw== [3/3]
  g54gcnUliSdYyTsowNt0yA== [3/3]
  jDsV392GiQxLshtK+ZAF6g== [3/3]
  wsLaB5pslJLUIHclhJO7wg== [3/3]
  PKMdT5oxQgTxreM+CO+bHw== [3/3]
  pyrDjzE1TFcjLkDjTkmqiA== [3/3]
  zEv7GRaegpKkTOlcdSbVyA== [3/3]
  +QD50DzrMPGkQMogX13s4w== [3/3]
  /ypFlGEbdpYbeojRyRBD/g== [3/3]
  roo4mYLIH9fH73PlTn0JKQ== [3/3]
  uUv26eYlXQd7nao7huwDKQ== [3/3]
  0Im8lcD9/RakW5RkdZrDmA== [3/3]
  DnQsk7podoetmNbt82sQqw== [3/3]
  l1Bf8PspWc+wXRHMBiJ6aw== [3/3]

dc1 (LAN):
  ===> c10: truncated key list response, showing first 35 of 51 keys
  ===> c11: truncated key list response, showing first 35 of 51 keys
  ===> c12: truncated key list response, showing first 35 of 51 keys
  ===> c13: truncated key list response, showing first 35 of 51 keys
  ===> c16: truncated key list response, showing first 35 of 51 keys
  ===> c2: truncated key list response, showing first 35 of 51 keys
  ===> c7: truncated key list response, showing first 35 of 51 keys
  ===> l: truncated key list response, showing first 35 of 51 keys
  ===> c1: truncated key list response, showing first 35 of 51 keys
  ===> c17: truncated key list response, showing first 35 of 51 keys
  ===> c18: truncated key list response, showing first 35 of 51 keys
  ===> c20: truncated key list response, showing first 35 of 51 keys
  ===> c4: truncated key list response, showing first 35 of 51 keys
  ===> c5: truncated key list response, showing first 35 of 51 keys
  ===> s1: truncated key list response, showing first 35 of 51 keys
  ===> s2: truncated key list response, showing first 35 of 51 keys
  ===> c14: truncated key list response, showing first 35 of 51 keys
  ===> c3: truncated key list response, showing first 35 of 50 keys
  ===> c6: truncated key list response, showing first 35 of 51 keys
  ===> c15: truncated key list response, showing first 35 of 51 keys
  ===> c19: truncated key list response, showing first 35 of 51 keys
  ===> c8: truncated key list response, showing first 35 of 51 keys
  ===> c9: truncated key list response, showing first 35 of 51 keys
  PKMdT5oxQgTxreM+CO+bHw== [23/23]
  uUv26eYlXQd7nao7huwDKQ== [23/23]
  kgX+E0XmXYefBxwAuNY9Lw== [23/23]
  nPhbUOxxfVO0waK/Q4/lhg== [23/23]
  pyrDjzE1TFcjLkDjTkmqiA== [23/23]
  vA7+zGspI45mW+bZHXbyRQ== [23/23]
  /ypFlGEbdpYbeojRyRBD/g== [22/23]
  AEQVHZOXCYAHuqBqx8kb1Q== [23/23]
  N4J2duCWwwY7/QikpqtqRg== [23/23]
  mdQsc9vIOxwNOjyk4Pgo5g== [23/23]
  uGEHpx1Uy/rLEy5x5vpYew== [23/23]
  wsLaB5pslJLUIHclhJO7wg== [23/23]
  J+It1aLhS1Lv8kJMEh7Z3g== [23/23]
  OvEV7rcTLSapFpKiG0jjGw== [23/23]
  Tq416DQdzmPCSTAyGSlLHA== [23/23]
  Um7HOKl7x0hdfR0crjPY/A== [23/23]
  keGbbBa2y8eGvTOxyOhwQw== [23/23]
  sdYIE5FHxhJ4tp/OWs0+bA== [1/23]
  /B7pNWgPFYl7USV+WPLqAA== [23/23]
  1Ty40u6Dk8TfS/d9tgKjsQ== [23/23]
  SrMp0SvH/At/s8kpSs5nKw== [23/23]
  d0w0FM3LvmSArte2mS9Y3w== [23/23]
  roo4mYLIH9fH73PlTn0JKQ== [23/23]
  34jTVOtF/Qw2/TrATsIiIw== [23/23]
  9kZ2mJ94E9mFnM9DyQsGAA== [23/23]
  DnQsk7podoetmNbt82sQqw== [23/23]
  jDsV392GiQxLshtK+ZAF6g== [23/23]
  l1Bf8PspWc+wXRHMBiJ6aw== [23/23]
  tL6kLg1kZW/ry5Gk8njR9g== [23/23]
  +QD50DzrMPGkQMogX13s4w== [23/23]
  0Im8lcD9/RakW5RkdZrDmA== [23/23]
  9f4Y+1AbSh2UxkYO6LyYGw== [23/23]
  g54gcnUliSdYyTsowNt0yA== [23/23]
  XgVr0n8l3qWwI66keY5cmw== [23/23]
  jNlaF7ahFUxhEGYIzH6pxA== [23/23]
  zEv7GRaegpKkTOlcdSbVyA== [23/23]

[rboyer]

Does it matter that these messages will be randomly ordered? If you stored them as something like [][]string instead of map[string]string then at least you could retain the ordering.

[hanshasselberg]

Messages are already in the response from

consul/agent/structs/structs.go

Lines 1337 to 1345 in 884b2e0

	type KeyringResponse struct {
	WAN bool
	Datacenter string
	Segment string
	Messages map[string]string `json:",omitempty"`
	Keys map[string]int
	NumNodes int
	Error string `json:",omitempty"`
	}

I only added it here so that it gets deserialized.

Since the results are collected in parallel from all the nodes, I wouldn't even be sure how to order them. The order of arrival could be different every time as well.