/ 
App-FuguVM-0.1.1
/ App::FuguVM::Proxy

NAME

App::FuguVM::Proxy - the OpenBSD mirror policy over Fugu::Proxy

SYNOPSIS

use App::FuguVM::Proxy;

my $proxy = App::FuguVM::Proxy->new(
    cache   => App::FuguVM::Proxy::Cache->new($cache_dir),
    pidfile => $state->proxy_pidfile,
    store   => $state->store,
    child   => 'App::FuguVM::Proxy',
    logfile => $state->vm_state_dir . '/proxy.log',
);

my $port = $proxy->start;
my $url  = $proxy->guest_url;    # http://10.0.2.2:<port>

DESCRIPTION

An OpenBSD installation downloads a miniroot image and a full set of file sets. A second installation downloads them again. This proxy keeps them, thus a repeated install reads from the disk.

Fugu::Proxy holds the serve loop, the cache and the metadata. This file holds only what is true of an OpenBSD mirror and of a QEMU guest.

The file has two packages. App::FuguVM::Proxy inherits the supervisor and adds the guest URL. App::FuguVM::Proxy::Cache inherits the cache and adds the mirror patterns and the version-scoped prune.

METHODS

Every method of Fugu::Proxy and Fugu::Proxy::Cache applies. These are the additions.

run_child

App::FuguVM::Proxy->run_child($port, $cache_dir)

The entry point of the spawned child. The child builds its own cache, warms the metadata table, and serves until a SIGTERM arrives.

guest_url

$proxy->guest_url

Return the proxy URL as the guest reaches it. QEMU user-mode networking puts the host at 10.0.2.2, and no other address gets out of the SLIRP network. The loopback address serves the same proxy, but the guest cannot reach it.

The method returns undef while the proxy does not run.

prune

my $removed = $cache->prune(@keep_versions);

Remove the cached download tree of every OpenBSD version other than the ones named. The method returns an array reference of { version, path, size }, one for each removed tree.

Nothing else bounds this cache. fuguvm cache clear --stale prunes installed images, which live beside these downloads under the same cache_dir, but no common key connects them. Thus a version bump left the full file sets of the previous version behind for good. Nothing read them again, because every cacheable pattern is version-scoped, and every copy that a continuous-integration cache made still carried them.

The method removes whole directories and not matching files. Removal of the files alone leaves the empty version tree behind, and a continuous-integration cache walks that tree.

The method does not touch a directory whose name is not a version. In practice there are none: every pattern puts its content under pub/OpenBSD/<version>/ or pub/OpenBSD/syspatch/<version>/. A cache under $HOME is the wrong place to delete on a guess.

CACHEABLE CONTENT

The cache keeps the release file sets, the packages, the syspatch sets, the checksums and their signatures, the miniroot images, the kernels, the build info and the index files. Every pattern names a version, and that is what makes prune safe.

Everything else is not cacheable, and neither is any response whose status is not 200. A cached 404 is a mirror that stays broken after the upstream is fixed.

SEE ALSO

Fugu::Proxy, App::FuguVM::Miniroot, App::FuguVM::Guest

AUTHOR

Dick Olsson <hi@senzilla.io>