cephadm: create systemd_unit.py for systemd unit related functions

Continue to modularize cephadm by moving the functions related to
generating systemd unit files to a new module.

Signed-off-by: John Mulligan <jmulligan@redhat.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/src/cephadm/cephadmlib/systemd_unit.py b/src/cephadm/cephadmlib/systemd_unit.py
new file mode 100644
index 00000000000..849833804c2
--- /dev/null
+++ b/src/cephadm/cephadmlib/systemd_unit.py
@@ -0,0 +1,73 @@
+# systemd_unit.py - creating/managing systemd unit files
+
+import os
+
+from . import templating
+from .call_wrappers import call_throws
+from .container_engines import Docker, Podman
+from .context import CephadmContext
+from .file_utils import write_new
+from .logging import write_cluster_logrotate_config
+
+
+def get_unit_file(ctx: CephadmContext, fsid: str) -> str:
+    has_docker_engine = isinstance(ctx.container_engine, Docker)
+    has_podman_engine = isinstance(ctx.container_engine, Podman)
+    has_podman_split_version = (
+        has_podman_engine and ctx.container_engine.supports_split_cgroups
+    )
+    return templating.render(
+        ctx,
+        templating.Templates.ceph_service,
+        fsid=fsid,
+        has_docker_engine=has_docker_engine,
+        has_podman_engine=has_podman_engine,
+        has_podman_split_version=has_podman_split_version,
+    )
+
+
+def install_base_units(ctx, fsid):
+    # type: (CephadmContext, str) -> None
+    """
+    Set up ceph.target and ceph-$fsid.target units.
+    """
+    # global unit
+    existed = os.path.exists(ctx.unit_dir + '/ceph.target')
+    with write_new(ctx.unit_dir + '/ceph.target', perms=None) as f:
+        f.write('[Unit]\n'
+                'Description=All Ceph clusters and services\n'
+                '\n'
+                '[Install]\n'
+                'WantedBy=multi-user.target\n')
+    if not existed:
+        # we disable before enable in case a different ceph.target
+        # (from the traditional package) is present; while newer
+        # systemd is smart enough to disable the old
+        # (/lib/systemd/...) and enable the new (/etc/systemd/...),
+        # some older versions of systemd error out with EEXIST.
+        call_throws(ctx, ['systemctl', 'disable', 'ceph.target'])
+        call_throws(ctx, ['systemctl', 'enable', 'ceph.target'])
+        call_throws(ctx, ['systemctl', 'start', 'ceph.target'])
+
+    # cluster unit
+    existed = os.path.exists(ctx.unit_dir + '/ceph-%s.target' % fsid)
+    with write_new(ctx.unit_dir + f'/ceph-{fsid}.target', perms=None) as f:
+        f.write(
+            '[Unit]\n'
+            'Description=Ceph cluster {fsid}\n'
+            'PartOf=ceph.target\n'
+            'Before=ceph.target\n'
+            '\n'
+            '[Install]\n'
+            'WantedBy=multi-user.target ceph.target\n'.format(
+                fsid=fsid)
+        )
+    if not existed:
+        call_throws(ctx, ['systemctl', 'enable', 'ceph-%s.target' % fsid])
+        call_throws(ctx, ['systemctl', 'start', 'ceph-%s.target' % fsid])
+
+    # don't overwrite file in order to allow users to manipulate it
+    if os.path.exists(ctx.logrotate_dir + f'/ceph-{fsid}'):
+        return
+
+    write_cluster_logrotate_config(ctx, fsid)