Node.js Core Dump Resurrector

by mmarchini 5 years ago

GNU/Linux ◆ xterm-256color ◆ zsh 248 views

See: https://github.com/mmarchini/node/tree/necromancer/lldb_v8

lldb_v8 commands:

v8 load: Bootstaps the Postmortem Host, copying memory from the core dump into the host process (not required, will be run by the other commands if the host is not running)
v8 stack: Prints the stack trace using Isolate::PrintStack()
v8 print <addr>: Prints the content of an object using Object::Print()

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You can download this recording in asciicast v2 format, as a .cast file.

Download

Replay in terminal

You can replay the downloaded recording in your terminal using the asciinema play command:

asciinema play 227038.cast

If you don't have asciinema CLI installed then see installation instructions.

Use with stand-alone player on your website

Download asciinema player from the releases page (you only need .js and .css file), then use it like this:

<!DOCTYPE html>
<html>
<head>
  <link rel="stylesheet" type="text/css" href="asciinema-player.css" />
</head>
<body>
  <div id="player"></div>
  <script src="asciinema-player.min.js"></script>
  <script>
    AsciinemaPlayer.create(
      '/assets/227038.cast',
      document.getElementById('player'),
      { cols: 88, rows: 30 }
    );
  </script>
</body>
</html>

See asciinema player quick-start guide for full usage instructions.

While this site doesn't offer GIF conversion at the moment, you can still do it yourself with the help of asciinema GIF generator utility - agg.

Once you have it installed run the following command to create GIF file:

agg https://asciinema.org/a/227038 227038.gif

Or, if you already downloaded the recording file:

agg 227038.cast 227038.gif

Check agg --help for all available options. You can change font family and size, select color theme, adjust speed and more.

See agg manual for full usage instructions.