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observer_cli

Build Status GitHub tag MIT License Hex.pm Version Hex.pm Downloads

Visualize Erlang/Elixir Nodes On The Command Line base on recon. Document in detail.

Goal

Installation

Erlang

%% rebar.config
{deps, [observer_cli]}
%% erlang.mk
dep_observer_cli = hex 1.8.2

Elixir

# mix.exs
   def deps do
     [{:observer_cli, "~> 1.8"}]
   end

How-To

Try in local shell.

%% rebar3 project
rebar3 shell
1> observer_cli:start().
%% mix project
iex -S mix
iex(1)> :observer_cli.start

Monitor remote node

%% rebar3 project
rebar3 shell --name 'observer_cli@127.0.0.1'
1> observer_cli:start('target@host', 'magic_cookie').
%% mix project
iex --name "observer_cli@127.0.0.1" -S mix
iex(1)> :observer_cli.start(:'target@host', :'magic_cookie')

:exclamation: ensure observer_cli application been loaded on target node.

Try in Elixir 1.9.x release

%% create elixir release
mix release
%% rpc current node
_build/dev/rel/example/bin/example rpc ":observer_cli.start"

:exclamation: ensure observer_cli application been loaded on current node.

Escriptize

  1. cd path/to/observer_cli/
  2. rebar3 escriptize to generate an escript executable containing the project's and its dependencies' BEAM files. Place script(_build/default/bin/observer_cli) anywhere in your path and use observer_cli command.
  3. observer_cli TARGETNODE [TARGETCOOKIE REFRESHMS] to monitor remote node.

DEMO

Home

How to write your own plugin?

If you need to customize some of your internal metrics and integrate it into observer_ci, you only need to write a observer_cli_plugin behaviour in a few simple steps to get a nice presentation.

  1. Configure observer_cli，tell observer_cli how to find your plugin.
%% module       - Specific module implements plugin behavior. It's mandatory.
%% title        - Menu title. It's mandatory.
%% shortcut     - Switch plugin by shortcut. It's mandatory.
%% interval     - Refresh interval ms. It's optional. default is 1500ms.
%% sort_column  - Sort the sheet by this index. It's optional default is 2.

{plugins,
  [
    #{module => observer_cli_plug_behaviour_x, title => "XPlug",
      interval => 1600, shortcut => "X", sort_column => 3},
    #{module => observer_cli_plug_behaviour_y, title => "YPlug",
      interval =>2000, shortcut => "Y", sort_column => 3}
  ]
}

The main view is HOME by default(observer_cli:start()). If you want to plugin view as main view, DO:your_cli:start().

% your_cli.erl
start() -> observer_cli:start_plugin().
  1. Write observer_cli_plugin behaviour. observer_cli_plugin has 3 callbacks.

2.1 attributes.

-callback attributes(PrevState) -> {[Rows], NewState} when
    Rows :: #{content => string()|integer()|{byte, pos_integer()},
              width => pos_integer(), color => binary()}.

for example:

attributes(PrevState) ->
  Attrs = [
    [
      #{content => "XXX Ets Size", width => 15},
      #{content => 122, width => 10},
      #{content => "Memory Capcity", width => 15},
      #{content => {percent, 0.12}, width => 16},
      #{content => "XYZ1 Process Mem", width => 19},
      #{content => {byte, 1023 * 1203}, width => 19}
    ],
    [
      #{content => "YYY Ets Size", width => 15},
      #{content => 43, width => 10},
      #{content => "Disk Capcity", width => 15},
      #{content => {percent, 0.23}, width => 16},
      #{content => "XYZ2 Process Mem", width => 19},
      #{content => {byte, 2034 * 220}, width => 19}
    ],
    [
      #{content => "ZZZ Ets Size", width => 15},
      #{content => 108, width => 10},
      #{content => "Volume Capcity", width => 15},
      #{content => {percent, 0.101}, width => 16},
      #{content => "XYZ3 Process Mem", width => 19},
      #{content => {byte, 12823}, width => 19}
    ]
  ],
  NewState = PrevState,
  {Attrs, NewState}.

|Home(H)|XPlug(X)|YPlug(Y)| | 0Days 3:34:50 |
|XXX Ets Size | 122 | Memory Capcity | 12.00% | XYZ1 Process Mem | 1.1737 MB |
|YYY Ets Size | 43 | Disk Capcity | 23.00% | XYZ2 Process Mem | 436.9922 KB |
|ZZZ Ets Size | 108 | Volume Capcity | 10.10% | XYZ3 Process Mem | 12.5225 KB |

-callback sheet_header() -> [SheetHeader] when
    SheetHeader :: #{title => string(), width => pos_integer(), shortcut => string()}.

for example:

sheet_header() ->
  [
    #{title => "Pid", width => 15},
    #{title => "Register", width => 20},
    #{title => "Memory", width => 20, shortcut => "S"},
    #{title => "Reductions", width => 23, shortcut => "R"},
    #{title => "Message Queue Len", width => 23, shortcut => "Q"}
  ].

|No |Pid |Register |Memory(S) |Reductions(R) |Message Queue Len(Q) |

-callback sheet_body(PrevState) -> {[SheetBody], NewState} when
    PrevState :: any(),
    SheetBody :: list(),
    NewState :: any().

for example:

sheet_body(PrevState) ->
  Body = [
    begin
      Register =
        case erlang:process_info(Pid, registered_name) of
          [] -> [];
          {_, Name} -> Name
        end,
      [
        Pid,
        Register,
        {byte, element(2, erlang:process_info(Pid, memory))},
        element(2, erlang:process_info(Pid, reductions)),
        element(2, erlang:process_info(Pid, message_queue_len))
      ]
    end
    || Pid <- erlang:processes()
  ],
  NewState = PrevState,
  {Body, NewState}.

Support {byte, 1024*10} to 10.0000 KB; {percent, 0.12} to 12.00%.

|No |Pid |Register |Memory(S) |Reductions(R) |Message Queue Len(Q) |
|1 |<0.242.0> | | 4.5020 MB | 26544288 | 0 |
|2 | <0.206.0> | | 1.2824 MB | 13357885 | 0 |
|3 | <0.10.0> | erl_prim_loader | 1.0634 MB | 10046775 | 0 |
|4 | <0.434.0> | | 419.1719 KB | 10503690 | 0 |
|5 | <0.44.0> | application_contro | 416.6250 KB | 153598 | 0 |
|6 | <0.50.0> | code_server | 416.4219 KB | 301045 | 0 |
|7 | <0.9.0> | rebar_agent | 136.7031 KB | 1337603 | 0 |
|8 | <0.207.0> | | 99.3125 KB | 9629 | 0 |
|9 | <0.58.0> | file_server_2 | 41.3359 KB | 34303 | 0 |
|10 | <0.209.0> | | 27.3438 KB | 31210 | 0 |
|11 | <0.0.0> | init | 25.8516 KB | 8485 | 0 |
|refresh: 1600ms q(quit) Positive Number(set refresh interval time ms) F/B(forward/back) Current pages is 1 |

Support F/B to page up/down.

A more specific plugin can collect linux system information such as kernel vsn, loadavg, disk, memory usage, cpu utilization, IO statistics.

Changelog

Contributors


zhongwencool
πŸ’»
Dimitrios Zorbas
πŸ’»
taotao
πŸ’»
Trevor Brown
πŸ’»
Zaiming Shi
πŸ’»

License

See the LICENSE file for license rights and limitations (MIT).

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