display pids instead of nodesbug21963

The challenge here was to find a way to display pids portably,
s.t. the same pid is displayed in the same way everywhere, every time.

We exploit Erlang's well-defined and stable external term format to
take apart pids.

2 files changed, 13 insertions, 14 deletions

diff --git a/docs/rabbitmqctl.1.pod b/docs/rabbitmqctl.1.pod
index 6b420872..43c38f6b 100644
--- a/docs/rabbitmqctl.1.pod
+++ b/docs/rabbitmqctl.1.pod
@@ -198,9 +198,9 @@ whether the queue will be deleted when no longer used
 
 queue arguments
 
-=item node
+=item pid
 
-node on which the process associated with the queue resides
+id of the Erlang process associated with the queue
 
 =item messages_ready
 
@@ -297,7 +297,7 @@ I<user>, I<peer_address>, I<peer_port> and I<state> are assumed.
 
 =item node
 
-node on which the process associated with the connection resides
+id of the Erlang process associated with the connection
 
 =item address
 
diff --git a/src/rabbit_control.erl b/src/rabbit_control.erl
index f89b96bd..5ecbe08c 100644
--- a/src/rabbit_control.erl
+++ b/src/rabbit_control.erl
@@ -173,7 +173,7 @@ The list_queues, list_exchanges and list_bindings commands accept an optional
 virtual host parameter for which to display results. The default value is \"/\".
 
 <QueueInfoItem> must be a member of the list [name, durable, auto_delete, 
-arguments, node, messages_ready, messages_unacknowledged, messages_uncommitted, 
+arguments, pid, messages_ready, messages_unacknowledged, messages_uncommitted, 
 messages, acks_uncommitted, consumers, transactions, memory]. The default is 
  to display name and (number of) messages.
 
@@ -183,7 +183,7 @@ auto_delete, arguments]. The default is to display name and type.
 The output format for \"list_bindings\" is a list of rows containing 
 exchange name, queue name, routing key and arguments, in that order.
 
-<ConnectionInfoItem> must be a member of the list [node, address, port, 
+<ConnectionInfoItem> must be a member of the list [pid, address, port, 
 peer_address, peer_port, state, channels, user, vhost, timeout, frame_max,
 recv_oct, recv_cnt, send_oct, send_cnt, send_pend]. The default is to display 
 user, peer_address, peer_port and state.
@@ -268,8 +268,7 @@ action(list_user_permissions, Node, Args = [_Username], Inform) ->
 action(list_queues, Node, Args, Inform) ->
     Inform("Listing queues", []),
     {VHostArg, RemainingArgs} = parse_vhost_flag_bin(Args),
-    ArgAtoms = list_replace(node, pid, 
-                            default_if_empty(RemainingArgs, [name, messages])),
+    ArgAtoms = default_if_empty(RemainingArgs, [name, messages]),
     display_info_list(rpc_call(Node, rabbit_amqqueue, info_all,
                                [VHostArg, ArgAtoms]),
                       ArgAtoms);
@@ -294,9 +293,7 @@ action(list_bindings, Node, Args, Inform) ->
 
 action(list_connections, Node, Args, Inform) ->
     Inform("Listing connections", []),
-    ArgAtoms = list_replace(node, pid,
-                            default_if_empty(Args, [user, peer_address,
-                                                    peer_port, state])),
+    ArgAtoms = default_if_empty(Args, [user, peer_address, peer_port, state]),
     display_info_list(rpc_call(Node, rabbit_networking, connection_info_all,
                                [ArgAtoms]),
                       ArgAtoms);
@@ -358,7 +355,7 @@ format_info_item(Key, Items) ->
                    is_tuple(Value) ->
             inet_parse:ntoa(Value);
         Value when is_pid(Value) ->
-            atom_to_list(node(Value));
+            pid_to_string(Value);
         Value when is_binary(Value) -> 
             escape(Value);
         Value when is_atom(Value) ->
@@ -403,6 +400,8 @@ escape_char([X | T], Acc) ->
 escape_char([], Acc) ->
     Acc.
 
-list_replace(Find, Replace, List) ->
-    [case X of Find -> Replace; _ -> X end || X <- List].
-
+pid_to_string(Pid) ->
+    <<131,103,100,NodeLen:16,NodeBin:NodeLen/binary,Id:32,Ser:32,_Cre:8>>
+        = term_to_binary(Pid),
+    Node = binary_to_term(<<131,100,NodeLen:16,NodeBin:NodeLen/binary>>),
+    lists:flatten(io_lib:format("<~w.~B.~B>", [Node, Id, Ser])).