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@trajano
Last active October 22, 2021 05:55
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Redeploy stack images if they do not match
#!/usr/bin/perl
use warnings;
use strict;
use Fatal qw(open);
our $VERSION = '1.0.0';
my $stack_name = shift;
sub _process_stack_entry {
my ($task_id, $task_image) = @_;
open my $container_fn, q{-|},
sprintf q#docker ps --filter "label=com.docker.swarm.task.id=%s" --no-trunc --format '{{.Image}} {{.ID}}'#, $task_id;
$_ = <$container_fn>;
(my ($image, $container_id) = m/^(\S+?)\s(\S+?)$/xms) || die "unable to parse '$_'\n";
$container_fn->close();
if ($image && $image ne $task_image) {
open my $container_inspect_fn, q{-|},
sprintf q#docker inspect --format '{{ index .Config.Labels "com.docker.swarm.service.name" }}' %s# , $container_id;
my $service_name = <$container_inspect_fn>;
chomp $service_name;
$container_inspect_fn->close();
open my $update_fn, q{-|},
sprintf 'docker service update -d --no-resolve-image --force --image %s %s', $task_image, $service_name;
my $updated_service_name = <$update_fn>;
chomp $updated_service_name;
$update_fn->close();
if ($service_name ne $updated_service_name) {
die "$service_name did not match $updated_service_name\n";
}
my $printed = (print "$updated_service_name\n");
if (!$printed) {
die "Unable to write to stdout\n";
}
}
return 1;
}
open my $tasks_fn, q{-|},
sprintf q#docker stack ps --format "{{.ID}} {{.Image}}" --filter "desired-state=running" --no-trunc %s#, $stack_name;
while (<$tasks_fn>) {
(my ($task_id, $task_image) = m/^(\S+?)\s(\S+)$/xms) || die "unable to parse '$_'\n";
_process_stack_entry($task_id, $task_image);
}
$tasks_fn->close();
@trajano
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trajano commented Nov 5, 2020

Since Docker does not provide a CLI for this one, this script will perform the update of the image if the images do not match.

moby/moby#31357
moby/moby#30951

This only works for development on a single node swarm.

@trajano
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trajano commented Nov 7, 2020

Code is now updated to pass "brutal" in http://perlcritic.com/

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