init-exporter

Utility for exporting services described by Procfile to init system. Supported init systems: upstart and systemd

• Installation
• Configuration
• Usage
  • Procfile v.1
  • Procfile v.2
• Exporting
• Command options
• Build status
• License

Installation

From source

To build the init-exporter from scratch, make sure you have a working Go 1.18+ workspace (instructions), then:

go get -d github.com/funbox/init-exporter
cd $GOPATH/src/github.com/funbox/init-exporter
make deps all
sudo make install

From ESSENTIAL KAOS Public Repository

sudo yum install -y https://yum.kaos.st/kaos-repo-latest.el$(grep 'CPE_NAME' /etc/os-release | tr -d '"' | cut -d':' -f5).noarch.rpm
sudo yum install init-exporter

Configuration

The export process can be configured through the config /etc/init-exporter.conf:

# Default configuration for init-exporter

[main]

  # Default run user
  run-user: service

  # Default run group
  run-group: service

  # Prefix used for exported units and helpers
  prefix: fb-

[procfile]

  # Enable/disable support of version 1 proc files
  version1: false

  # Enable/disable support of version 2 proc files
  version2: true

[paths]

  # Working dir
  working-dir: /tmp

  # Path to directory with helpers
  helper-dir: /var/local/init-exporter/helpers

  # Path to directory with systemd configs
  systemd-dir: /etc/systemd/system

  # Path to directory with upstart configs
  upstart-dir: /etc/init

[defaults]

  # Number of Processes (0 - disabled)
  nproc: 10240

  # Number of File Descriptors (0 - disabled)
  nofile: 10240

  # Enable or disable respawn by default here
  respawn: true

  # Respawn count
  respawn-count: 10

  # Respawn interval
  respawn-interval: 15

  # Kill timeout (0 - disabled)
  kill-timeout: 60

[log]

  # Enable or disable logging here
  enabled: true

  # Log file directory
  dir: /var/log/init-exporter

  # Path to log file
  file: {log:dir}/init-exporter.log

  # Default log file permissions
  perms: 0644

  # Minimal log level (debug/info/warn/error/crit)
  level: info

To give a certain user (i.e. deployuser) the ability to use this script, you can place the following lines into sudoers file:

# Commands required for manipulating jobs
Cmnd_Alias UPSTART = /sbin/start, /sbin/stop, /sbin/restart
Cmnd_Alias SYSTEMD = /usr/bin/systemctl
Cmnd_Alias EXPORTER = /usr/local/bin/init-exporter

...

# Allow deploy user to manipulate jobs
deployuser        ALL=(deployuser) NOPASSWD: ALL, (root) NOPASSWD: UPSTART, SYSTEMD, EXPORTER

Usage

init-exporter is able to process two versions of Procfiles. Utility automatically recognises used format.

Procfile v.1

After init-exporter is installed and configured, you may export background jobs from an arbitrary Procfile-like file of the following format:

cmdlabel1: cmd1
cmdlabel2: cmd2

i.e. a file ./myprocfile containing:

my_tail_cmd: /usr/bin/tail -F /var/log/messages
my_another_tail_cmd: /usr/bin/tail -F /var/log/messages

For security purposes, command labels are allowed to contain only letters, digits, and underscores.

Procfile v.2

Another format of Procfile scripts is YAML config. A configuration script may look like this:

version: 2

start_on_runlevel: 3
stop_on_runlevel: 3

env:
  RAILS_ENV: production
  TEST: true

working_directory: /srv/projects/my_website/current

commands:
  my_tail_cmd:
    command: /usr/bin/tail -F /var/log/messages
    respawn:
      count: 5
      interval: 10
    env:
      RAILS_ENV: staging # if needs to be redefined or extended
    working_directory: '/var/...' # if needs to be redefined

  my_another_tail_cmd:
    command: /usr/bin/tail -F /var/log/messages
    kill_timeout: 60
    kill_signal: SIGQUIT
    reload_signal: SIGUSR2
    env_file: shared/staging.env
    respawn: false # by default respawn option is enabled

  my_one_another_tail_cmd:
    pre: /usr/bin/echo pre_command
    command: /usr/bin/tail -F /var/log/messages
    post: /usr/bin/echo post_command
    log: /var/log/messages_copy

  my_multi_tail_cmd:
    command: /usr/bin/tail -F /var/log/messages
    count: 2

start_on_runlevel and stop_on_runlevel are two global options that can't be redefined per-command.

working_directory will generate the following line:

cd 'your/working/directory' && your_command

env params can be redefined and extended in per-command options. Note that you can't remove a globally defined env variable. For Procfile example given earlier the generated command will look like:

env RAILS_ENV=staging TEST=true your_command

log option lets you override the default log location (/var/log/fb-my_website/my_one_another_tail_cmd.log).

kill_timeout option lets you override the default process kill timeout of 30 seconds.

kill_signal specifies which signal to use when killing a service.

reload_signal specifies which signal to use when reloading a service.

env_file absolute or relative path to file with environment variables.

respawn option controls how often the job can fail. If the job restarts more often than count times in interval, it won't be restarted anymore.

Options working_directory, env, log, respawn can be defined both as global and as per-command options.

Exporting

To export a Procfile you should run

sudo init-exporter -p ./myprocfile -f format myapp

Where myapp is the application name. This name only affects the names of generated files. For security purposes, app name is also allowed to contain only letters, digits and underscores.

Format is name of init system (upstart | systemd).

Assuming that default options are used, the following files and folders will be generated (in case of upstart format):

in /etc/init/:

fb-myapp-my_another_tail_cmd.conf
fb-myapp-my_tail_cmd.conf
fb-myapp.conf

in /var/local/init-exporter/helpers:

fb-myapp-my_another_tail_cmd.sh
fb-myapp-my_tail_cmd.sh

Prefix fb- (which can be customised through config) is added to avoid collisions with other jobs. After this my_tail_cmd, for example, will be able to be started as an Upstart job:

sudo start fb-myapp-my_tail_cmd
...
sudo stop fb-myapp-my_tail_cmd

It's stdout/stderr will be redirected to /var/log/fb-myapp/my_tail_cmd.log.

To start/stop all application commands at once, you can run:

sudo start fb-myapp
...
sudo stop fb-myapp

To remove init scripts and helpers for a particular application you can run

sudo init-exporter -u -f upstart myapp

The logs are not cleared in this case. Also, all old application scripts are cleared before each export.

Command options

Usage: init-exporter {options} app-name

Options

  --procfile, -p file             Path to procfile
  --dry-start, -d                 Dry start (don't export anything, just parse and test procfile)
  --disable-validation, -D        Disable application validation
  --unistall, -u                  Remove scripts and helpers for a particular application
  --format, -f upstart|systemd    Format of generated configs
  --no-colors, -nc                Disable colors in output
  --help, -h                      Show this help message
  --version, -v                   Show version

Examples

  init-exporter -p ./myprocfile -f systemd myapp
  Export given procfile to systemd as myapp

  init-exporter -u -f systemd myapp
  Uninstall myapp from systemd

  init-exporter -p ./myprocfile -f upstart myapp
  Export given procfile to upstart as myapp

  init-exporter -u -f upstart myapp
  Uninstall myapp from upstart

Build status

Branch	Status
Stable
Unstable

License

init-exporter is released under the MIT license (see LICENSE)