puppet: Move wal-g to external_dep, in /srv/zulip-wal-g-*.

puppet/zulip/manifests/postgresql_backups.pp

@@ -4,18 +4,28 @@ class zulip::postgresql_backups {
   include zulip::postgresql_common
 
   $wal_g_version = '1.1.1-rc'
-  $bin = "/usr/local/bin/wal-g-${wal_g_version}"
+  $bin = "/srv/zulip-wal-g-${wal_g_version}"
   $package = "wal-g-pg-ubuntu-20.04-${::architecture}"
-  zulip::sha256_tarball_to { 'wal-g':
-    url     => "https://github.com/wal-g/wal-g/releases/download/v${wal_g_version}/${package}.tar.gz",
-    sha256  => 'eed4de63c2657add6e0fe70f8c0fbe62a4a54405b9bfc801b1912b6c4f2c7107',
-    install => {
-      'wal-g' => "/usr/local/bin/wal-g-${wal_g_version}",
-    },
+
+  # This tarball contains only a single file
+  zulip::external_dep { 'wal-g':
+    version        => $wal_g_version,
+    url            => "https://github.com/wal-g/wal-g/releases/download/v${wal_g_version}/${package}.tar.gz",
+    sha256         => 'eed4de63c2657add6e0fe70f8c0fbe62a4a54405b9bfc801b1912b6c4f2c7107',
+    tarball_prefix => $package,
   }
   file { '/usr/local/bin/wal-g':
-    ensure => 'link',
-    target => "/usr/local/bin/wal-g-${wal_g_version}",
+    ensure  => 'link',
+    target  => $bin,
+    require => Zulip::External_Dep['wal-g'],
+  }
+  # We used to install versions into /usr/local/bin/wal-g-VERSION,
+  # until we moved to using Zulip::External_Dep which places them in
+  # /srv/zulip-wal-g-VERSION.  Tidy old versions.
+  tidy { '/usr/local/bin/wal-g-*':
+    recurse => 1,
+    path    => '/usr/local/bin/',
+    matches => 'wal-g-*',
   }
   file { '/usr/local/bin/env-wal-g':
     ensure  => file,