batch sending of multiple values with timestamping enabled

[tverlaan]

Not sure if the title is clear enough, but I'll try to explain in more detail.

If both timestamping and batch_window_size is enabled (respectively true and something greater than zero) I get an error on no case clause matching

14:18:36.504 [error] CRASH REPORT Process exometer_report_influxdb with 0 neighbours crashed with reason: no case clause matching {[erlang,memory],#{<<"host">> => "timmov-mbp.local"},#{total => 50843616},1459513116503950} in exometer_report_influxdb:maybe_send/5 line 261

This happens when you define a metric as:

{ [:erlang, :memory], {:function, :erlang, :memory, [], :proplist, [:processes, :total]}, [] }]

And a subscription as:

{:exometer_report_influxdb, [:erlang, :memory], [:total, :processes], 5000, true, []}

This patch resets the timestamp so that for [:erlang, :memory] the timestamp is taken from the latest in the list (one of these: [:total, :processes]).

The result of this patch is this (ngrep):

erlang_memory,host=timmov-mbp.local processes=8878072i,total=51101328i 1459514976146610

Which I think is mentioned in #14 (comment)

Please let me know if this is acceptable.

[surik]

Thank you!

[tverlaan]

Wow, that was quick! Thanks!