synit/TODO.md

• signals (SIGTERM)

• service-started, service-running, and service-complete

  • actually more like: stopped, starting, started, running, failed, and stopping.
  • ... but with complete added, to mirror failed.
  • service controls: reload?, restart, pause, unpause, force-stop ("blocked")
  • difference between "pause" and "block" is that "pause" stops the actual program instance but doesn't flag the service as non-started, while "block" pushes it all the way back to "stopped".

• deal with logging

  • when syslogd is running, /dev/log is a unix datagram socket

• service for apk operations - otherwise they clash

Service lifecycle (as freely imagined; really, a state machine similar to this will be induced by assertion-driven subconversations/facets...):

digraph G {
    compound=true;

    subgraph cluster_runnable {
        label="Runnable";
        running [label="running\n(a.k.a. ready)"];
        starting -> started [label="deps satisfied\nstart svc"];
        started -> running [label="marked running\n-"];
        started -> failed [label="start failed\n-"];
        started -> complete [label="svc done\n-"];
        running -> failed [label="svc failed\n-"];
        running -> complete [label="svc done\n-"];
        failed -> started [label="restart\nstart svc"];
        complete -> started [label="restart\nstart svc"];
        running -> started [label="restart\nstart svc"];
    }
    stopped;
    paused [label="running\n(paused)"];
    blocked [label="stopped\n(blocked)"];

    stopped -> starting [label="required\nscan deps"];
    running -> stopped [label="unrequired\nstop svc"];

    running -> paused [lhead=cluster_runnable, label="pause req\nstop svc"];
    paused -> starting [label="unpause req\nscan deps"];

    running -> blocked [lhead=cluster_runnable, label="block req\nstop svc"];
    blocked -> stopped [label="unblock req\ncheck for requirement"];

    paused -> blocked [label="block req\n-"];
}

Oh, how about having a set-of-states approach: one for the supervision/dependency-resolution process, and one for the service itself?