Mk-Chan / procman

A process control system alternative to supervisord and systemd functionality

ProcMan

A simple process control solution. The intended use case is for this application to be started by a native init-system such as systemd or crontab and then used for further process management itself.

Each process registered with ProcMan is called a job and is simply a shell command that will be executed using a system() call. Most likely sh -c <command> on a common GNU/Linux distribution.

Metadata about jobs is stored in an sqlite3 database.

Concepts

A job is a process configuration that has a type will be executed with some schedule. There are 2 types of jobs:

1. OneTime one_time - Will run once on-schedule/on-demand and wait till next actuation.
2. Continuous continuous - Will run continuously, restarting on failure with backoff once begun.

Currently, only a single schedule is supported: reboot. This will simply start the job when ProcMan runs. Any other value is ignored, and the job will need to be started manually.

Job stdout is redirected to a local folder logs/<jobname>/<unix-timestamp-of-runtime>.log. A job can be found in one of several states at any time during its lifetime (inspired by supervisord):

Stopped
Starting
Running
Retrying
Error - not yet implemented
Stopping
Exited
Unknown - not yet implemented

Example

• Start ProcMan:

./procman 10000

• Create a simple job that echos "hello":

curl --request POST \
  --url http://localhost:10000/job/create \
  --header 'content-type: application/json' \
  --data '{
	"name": "test",
	"command": "echo hello",
	"type": "one_time",
	"schedule": "reboot"
}'

That should create a logs/test/<unix-timestamp>.log file with hello written inside. The job we created ran automatically because we set a reboot schedule.

• Try to run the job again:

curl http://localhost:10000/job/test/start

That will once again create a new log file with the same content as the last.

• Similarly, a running job can be stopped with:

curl http://localhost:10000/job/test/stop

This is also the only way to stop a continuous job once it has been started barring failure. The entire API is provided below.

API

Job CRUD operations
===================
/jobs - GET to list all jobs
/job/{name} - GET to retrieve job metadata
/job/create - POST to add a new job
/job/replace/{name} - PUT to replace job
/job/delete/{name} - DELETE to disable job

Job State Control & Query
=========================
/jobs/states - GET to list all job states
/job/{name}/start - GET to start job
/job/{name}/stop - GET to stop job
/job/{name}/restart - GET to restart job
/job/{name}/state - GET to retrieve job state

Setup

Requires Go 1.14 to build.

1. Clone the repository git clone https://github.com/Mk-Chan/procman
2. Build the code from the repository go build
3. Start the app ./procman <webserver-port>