Add failed and list options

backstep-traceback-auto will now cache a list of failed backups. As
a result I can now add an option to list the lv's that have not been
backed up and an option to back them up.
Signed-off-by: Robert Spencer <rspencer@lbsd.net>

scripts/backstep-traceback-auto

@@ -21,6 +21,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 import argparse
 import ast
 import configparser
+from datetime import datetime
+import json
 import os
 import subprocess
 import sys
@@ -37,7 +39,14 @@ parser.add_argument(
 )
 group = parser.add_mutually_exclusive_group()
 group.add_argument("-d", "--daily", action="store_true", help="Do daily backups")
+group.add_argument("-f", "--failed", action="store_true", help="Do failed backups")
 group.add_argument("-w", "--weekly", action="store_true", help="Do weekly backups")
+parser.add_argument(
+    "-l",
+    "--list-failed",
+    action="store_true",
+    help="List lv's from last failed backup",
+)
 parser.add_argument(
     "-o", "--only", help="Only do a backup of the specified lv", metavar="lv_name"
 )
@@ -45,18 +54,47 @@ parser.add_argument(
     "-t",
     "--test",
     action="store_true",
-    help="Don't do anything, only show what would have been run.",
+    help="Don't do anything, only show what would have been run",
 )
 args = parser.parse_args()
 
+if not args.test:
+    if not os.path.exists("/var/run/backstep-traceback-auto"):
+        os.mkdir("/var/run/backstep-traceback-auto")
+
+    JSON_FILE = "/var/run/backstep-traceback-auto/backstep-traceback-auto.json"
+else:
+    JSON_FILE = "backstep-traceback-auto.json"
+
+if os.path.exists(JSON_FILE):
+    with open(JSON_FILE, encoding="utf8") as json_file:
+        json_dict = json.load(json_file)
+
+    PERIOD = json_dict["period"]
+    lv_list = json_dict["lv_list"]
+
 if args.daily:
     PERIOD = "daily"
-elif args.weekly:
+
+if args.failed:
+    if os.path.exists(JSON_FILE):
+        os.remove(JSON_FILE)
+
+if args.weekly:
     PERIOD = "weekly"
-else:
+
+if not PERIOD:
     print("error: You need to specify a period [daily or weekly].")
     sys.exit(2)
 
+if args.list_failed:
+    if lv_list:
+        print(json.dumps(lv_list, indent=4))
+    else:
+        print("error: There is no failed backup list.")
+
+    sys.exit(0)
+
 if not args.test:
     CONFIG_FILE = "/etc/backstep-traceback/backstep-traceback-auto.ini"
 else:
@@ -110,9 +148,12 @@ else:
         if bwlimit > 0:
             syncopts.append("--bwlimit=" + str(bwlimit))
 
-stack = []
+if not lv_list:
+    lv_list = ast.literal_eval(config.get(PERIOD, "backup_lvs"))
+
+stack_dict = {}
 
-for lv in reversed(ast.literal_eval(config.get(PERIOD, "backup_lvs"))):
+for lv in lv_list:
     if args.only and args.only != lv:
         continue
 
@@ -166,7 +207,7 @@ for lv in reversed(ast.literal_eval(config.get(PERIOD, "backup_lvs"))):
         )
     )
 
-    stack.append(command_line)
+    stack_dict[lv] = command_line
 
 #   Rsync Exit Values
 #   0      Success
@@ -190,20 +231,36 @@ for lv in reversed(ast.literal_eval(config.get(PERIOD, "backup_lvs"))):
 #   30     Timeout in data send/receive
 #   35     Timeout waiting for daemon connection
 
-exit_list = [0, 1, 2, 3, 4, 6, 13, 14, 20, 21, 22, 24, 25]
+exit_list = [1, 2, 3, 4, 6, 13, 14, 20, 21, 22, 24, 25]
 wait_list = [5, 10, 11, 12, 23, 30, 35, 255]
 
-while stack:
-    task = stack.pop()
+lv_list.reverse()
 
-    EXIT_CODE = subprocess.call(task)
+while lv_list:
+    lv = lv_list.pop()
 
-    if EXIT_CODE in exit_list:
-        sys.exit(EXIT_CODE)
-    elif EXIT_CODE in wait_list:
-        stack.append(task)
+    EXIT_CODE = subprocess.call(stack_dict[lv])
+
+    if EXIT_CODE in wait_list:
+        lv_list.append(lv)
 
         if args.verbose:
             print("Sleeping...")
 
         time.sleep(3030)
+    elif EXIT_CODE in exit_list:
+        lv_list.append(lv)
+        lv_list.reverse()
+
+        json_dict = {}
+        json_dict["datetime"] = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
+        json_dict["exitcode"] = EXIT_CODE
+        json_dict["period"] = PERIOD
+        json_dict["lv_list"] = lv_list
+
+        with open(JSON_FILE, "w", encoding="utf8") as json_file:
+            json.dump(json_dict, json_file, indent=4)
+
+        sys.exit(EXIT_CODE)
+
+sys.exit(0)