logody

Just like docker compose but with normal programs.

Aggregates process output harmoniously.

Demo: https://asciinema.org/a/vJMpIfqfVAxHu8iWdRkNYcXW7

Disclaimer

This was implemented on a Friday afternoon and there may have been beer involved.

Yes, "logdog" is a much better name. Unfortunately it's already taken.

Before you send an issue about your program not listing output, check the buffering settings. Some usual suspects include grep --line-buffered, sed -l. Remember that GNU and BSD arguments are often different!

Features

• Run multiple processes in parallel
• Safely interleve logs
• Indicate process name on log-line
• Indicate handle on log-line (stdout, stderr)
• Indicate exit-codes on log-line after termination
• Aligns process-names and outputs as columns
• Supply shell strings
• Supply executables and lists of arguments
• Configure processes to restart on success
• Configure processes to restart on failure
• Specify subset of configuration processes via arguments
• Convenient arguments-only mode for simple concurrent processes
• YAML configuration file format (feature... or bug?)
• Optionally strips non-printable characters from output
• Kill all processes easily with Ctrl-C

Installing

This is a Haskell codebase.

You can install logody with stack.

Operation

Two modes of operation:

• Shell Arguments
• Configuration

Shell Arguments

If you don't supply any config input, then the arguments are interpreted as shell strings.

These will be named "process_N" sequentially and run until completion or failure.

Usage

Usage: logody [OPTIONS] [SHELL]* < CONFIG_FILE

    echo -n | logody SHELL*
    or...
    logody [NAME]* < CONFIG_FILE

Options:

 -h | --help       Print help and usage information.
 -v | --version    Print version information.
 -n | --no-config  Don't read any configuration, just accept shell string arguments.
 -f | --file       Specify config file. '-' for STDIN.

Configuration

If you supply configuration input, then your process list will be defined in the config file format.

Any arguments provided will be used to filter the process list.

Config Example

---
osname:
  process: uname
  args:
    - "-a"

echo:
  shell: "echo bar && sleep 1 && exit 1"
  resume:
    - fail

testscript:
  process: ./test/test.bash
  sanitise: False
  resume:
    - succeed
    - fail

Output:

$ logody < test/processes.yaml
testscript | Starting Process {"name":"testscript","resumption":{"succeed":true,"failure":true},"runner":{"tag":"Program","contents":["./test/test.bash",[]]}}
osname     | Starting Process {"name":"osname","resumption":{"succeed":false,"failure":false},"runner":{"tag":"Program","contents":["uname",["-a"]]}}
echo       | Starting Process {"name":"echo","resumption":{"succeed":false,"failure":true},"runner":{"tag":"Shell","contents":"echo bar && sleep 1 && exit 1"}}
osname     | stdout -> Darwin host.local ...
echo       | stdout -> bar
osname     | Exited Successfully
testscript | stdout -> test.bash 1
testscript | stdout -> test.bash 2
testscript | stdout -> test.bash 3
testscript | stdout -> test.bash 4
echo       | Failure -> Failed with code 1
echo       | Restarting process after failure with exit code 1
echo       | stdout -> bar
testscript | stdout -> test.bash 5
testscript | stdout -> test.bash 6
testscript | stdout -> test.bash 7
echo       | Failure -> Failed with code 1
echo       | Restarting process after failure with exit code 1
echo       | stdout -> bar
testscript | stdout -> test.bash 8
testscript | stdout -> test.bash 9
testscript | stdout -> test.bash 10
echo       | Failure -> Failed with code 1
echo       | Restarting process after failure with exit code 1
echo       | stdout -> bar
testscript | Exited Successfully
testscript | Restarting process after success
testscript | stdout -> test.bash 1
^C

Bugs

• No known bugs!

TODO

• Support other config formats: JSON, Dhall
• Color Lines
• Implement all of the applicable Docker-Compose features