def handle_proc_event()

in github-runner-ami/packer/files/runner-supervisor.py [0:0]

• 40 lines of code
• 7 McCabe index (conditional complexity)

    def handle_proc_event(self, sock, mask):
        try:
            data, (nlpid, nlgrps) = sock.recvfrom(1024)
        except OSError as e:
            if e.errno == errno.ENOBUFS:
                return
            raise
        if nlpid != 0:
            # Ignore messages from non-root processes
            return

        event, detail = proc_event.from_netlink_packet(data)
        if event.what == ProcEventWhat.EXEC:
            try:
                proc = psutil.Process(detail.pid)

                with proc.oneshot():
                    if proc.name() == "Runner.Worker":
                        log.info(
                            "Found new interesting processes, protecting from scale in %d: %s",
                            detail.pid,
                            proc.cmdline(),
                        )
                        self.interesting_processes[detail.pid] = proc
                        self.protect_from_scale_in(protect=True)
                        self.dynamodb_atomic_decrement()

            except psutil.NoSuchProcess:
                # We lost the race, process has already exited. If it was that short lived it wasn't that
                # interesting anyway
                pass
        elif event.what == ProcEventWhat.EXIT:
            if detail.pid in self.interesting_processes:
                log.info("Interesting process %d exited", detail.pid)
                del self.interesting_processes[detail.pid]

                if not self.interesting_processes:
                    log.info("Watching no processes, disabling termination protection")
                    self.protect_from_scale_in(protect=False)
            elif self.in_termating_lifecycle:
                try:
                    proc = psutil.Process(detail.pid)
                    if proc.name() == "Runner.Listener":
                        log.info("Runner.Listener process %d exited - OkayToTerminate instance", detail.pid)
                        complete_asg_lifecycle_hook('OkayToTerminate')
                except psutil.NoSuchProcess:
                    # We lost the race, process has already exited. If it was that short lived it wasn't that
                    # interesting anyway
                    pass