Convert backup shell script to Python.

This will allow us to add more functionality such as updating status
with backup information.

images/kubedrutil/kubedrutil/cli/commands/cmd_backup.py

@@ -0,0 +1,122 @@
+
+import os
+import json
+import pprint
+import subprocess
+import time
+
+import click
+
+from kubedrutil.cli import context
+from kubedrutil.common import kubeclient
+
+def get_config():
+    config = {}
+
+    for name in ["AWS_ACCESS_KEY", "AWS_SECRET_KEY", "RESTIC_PASSWORD",
+                 "ETCD_ENDPOINT", "ETCD_CREDS_DIR", "ETCD_SNAP_PATH",
+                 "RESTIC_REPO", "BACKUP_SRC", "KDR_POLICY_NAME"]:
+
+        val = os.environ.get(name, None)
+        if not val:
+            raise Exception("Env variable {} is not set".format(name))
+
+        config[name] = val
+
+    return config
+
+def build_snapshot_cmd(config):
+    cmd = [
+        "etcdctl",
+        "--endpoints={}".format(config["ETCD_ENDPOINT"]),
+        "--cacert={}/ca.crt".format(config["ETCD_CREDS_DIR"]),
+        "--cert={}/client.crt".format(config["ETCD_CREDS_DIR"]),
+        "--key={}/client.key".format(config["ETCD_CREDS_DIR"]),
+	"--debug", "snapshot", "save",
+        config["ETCD_SNAP_PATH"]
+    ]
+
+    return cmd
+
+def create_etcd_snapshot(config):
+    snapshot_cmd = build_snapshot_cmd(config)
+    print("Running the etcd snapshot command: ({})".format(snapshot_cmd))
+    os.environ["ETCDCTL_API"] = "3"
+
+    # etcdctl is writing debug information to STDERR so don't capture it.
+    resp = subprocess.run(snapshot_cmd, check=True, encoding='utf-8')
+
+    # The command doesn't return non-zero error code even when it fails
+    # (at least in some cases) so explicitly check for the snapshot file.
+    fileinfo = os.stat(config["ETCD_SNAP_PATH"])
+    if fileinfo.st_size <= 0:
+        raise Exception("etcd snapshot file {} has invalid size".format(config["ETCD_SNAP_PATH"]))
+
+    pprint.pprint(resp)
+
+def copy_certificates(config):
+    src_dir = config.get('CERTS_SRC_DIR', None)
+    dest_dir = config.get('CERTS_DEST_DIR', None)
+
+    if src_dir and dest_dir:
+        os.makedirs(dest_dir, exist_ok=True)
+        copy_cmd = ["cp", "-R",  '"{}"/*'.format(src_dir), '"{}"'.format(dest_dir)]
+        resp = subprocess.run(copy_cmd, stderr=subprocess.PIPE, check=True, encoding='utf-8', shell=True)
+        pprint.pprint(resp)
+
+def restic_backup(config):
+    restic_cmd = ["restic", "--json",  "-r",  config['RESTIC_REPO'],
+                  "--verbose", "backup",  config['BACKUP_SRC']]
+    print("Running restic backup command: ({})".format(restic_cmd))
+    resp = subprocess.run(restic_cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, check=True, 
+                          encoding='utf-8')
+    pprint.pprint("    rc = {}".format(resp.returncode))
+
+    # Find snapshot id. Process all the lines.
+    snapshot_id = None
+    print()
+    for line in resp.stdout.splitlines():
+        print(line)
+        line = line.strip()
+
+        if not line:
+            continue
+
+        data = json.loads(line)
+        if 'snapshot_id' in data:
+            snapshot_id = data['snapshot_id']
+
+    if not snapshot_id:
+        raise Exception("Could not find snapshot ID")
+
+    return snapshot_id
+
+def create_mbr(policy, snapshot_id):
+    mbr_name = "mbr-{}".format(snapshot_id)
+    print("mbr_name: {}".format(mbr_name))
+    mbr_api = kubeclient.MetadataBackupRecordAPI("kubedr-system")
+    mbr_spec = {
+        "snapshotId": snapshot_id,
+        "policy": policy
+    }
+    pprint.pprint(mbr_spec)
+    print("Creating MBR...")
+    mbr_api.create(mbr_name, mbr_spec)
+
+def backup(config):
+    create_etcd_snapshot(config)
+    copy_certificates(config)
+    snapshot_id = restic_backup(config)
+    create_mbr(config["KDR_POLICY_NAME"], snapshot_id)
+
+@click.command()
+@context.pass_context
+def cli(ctx):
+    """Perform backup of etcd and optionally, certificates as well.
+
+    """
+
+    config = get_config()
+    backup(config)
+    # Process more data from restic response and set status.
+    # Also check for command errors.

images/kubedrutil/kubedrutil/common/kubeclient.py

@@ -120,6 +120,12 @@ def __init__(self, namespace="default"):
         self.kind = "MetadataBackupPolicy"
         self.plural = "metadatabackuppolicies"
 
+class MetadataBackupRecordAPI(KubedrV1AlphaResource):
+    def __init__(self, namespace="default"):
+        super().__init__(namespace)
+        self.kind = "MetadataBackupRecord"
+        self.plural = "metadatabackuprecords"
+
 def create_backuploc_creds(name, access_key, secret_key, restic_password):
     creds_data = {
         "access_key": base64.b64encode(access_key.encode("utf-8")).decode("utf-8"),