Add options for important=yes userdata

Check if user-specified packages and user-specified commands are in
important lists and if so add userdata important=yes

Fixes #38.

extra/snap-pac.ini

@@ -2,6 +2,7 @@
 
 # Each section corresponds with a snapper configuration. Add additional sections to add
 # other configurations to be snapshotted. By default, only the root configuration is snapshotted.
+# Create a setion named [DEFAULT] to have a setting apply for all snapper configurations
 
 [root]
 # How many characters to limit the description for snapper.
@@ -19,6 +20,13 @@ cleanup_algorithm = number
 # Post snapshot description. Default is the list of packages involved in the pacman transaction
 #post_description = pacman post snapshot
 
+# Uncomment to add "important=yes" to userdata for snapshots referring to these packages
+#important_packages = ["linux"]
+
+# Uncomment to add "important=yes" to userdata for snapshots that were created with the
+#following commands
+#important_commands = ["pacman -Syu"]
+
 # Example for another snapper configuration named "home"
 # [home]
 # snapshot = True

scripts/snap_pac.py

@@ -18,6 +18,7 @@
 
 from argparse import ArgumentParser
 from configparser import ConfigParser
+import json
 import logging
 from pathlib import Path
 import os
@@ -30,7 +31,8 @@ logging.basicConfig(format="%(message)s", level=logging.INFO)
 
 class SnapperCmd:
 
-    def __init__(self, config, snapshot_type, cleanup_algorithm, description="", nodbus=False, pre_number=None):
+    def __init__(self, config, snapshot_type, cleanup_algorithm, description="",
+                 nodbus=False, pre_number=None, important=False):
         self.cmd = ["snapper"]
         if nodbus:
             self.cmd.append("--no-dbus")
@@ -40,6 +42,8 @@ class SnapperCmd:
         self.cmd.append("--print-number")
         if description:
             self.cmd.append(f"--description \"{description}\"")
+        if important:
+            self.cmd.append("--userdata \"important=yes\"")
         if snapshot_type == "post":
             if pre_number is not None:
                 self.cmd.append(f"--pre-number {pre_number}")
@@ -69,7 +73,7 @@ def setup_config_parser(ini_file, parent_cmd, packages):
         "snapshot": False,
         "cleanup_algorithm": "number",
         "pre_description": parent_cmd,
-        "post_description": packages,
+        "post_description": " ".join(packages),
         "desc_limit": 72
     }
     config["root"] = {
@@ -100,13 +104,25 @@ def get_pre_number(snapshot_type, prefile):
     return pre_number
 
 
+def check_important_commands(config, snapper_config, parent_cmd):
+    important_commands = json.loads(config.get(snapper_config, "important_commands"))
+    return parent_cmd in important_commands
+
+
+def check_important_packages(config, snapper_config, packages):
+    important_packages = json.loads(config.get(snapper_config, "important_packages"))
+    print(important_packages)
+    print(packages)
+    return any(x in important_packages for x in packages)
+
+
 def main(snap_pac_ini, snapper_conf_file, args):
 
     if os.getenv("SNAP_PAC_SKIP", "n").lower() in ["y", "yes", "true", "1"]:
         return False
 
     parent_cmd = os.popen(f"ps -p {os.getppid()} -o args=").read().strip()
-    packages = " ".join([line.rstrip("\n") for line in sys.stdin])
+    packages = [line.rstrip("\n") for line in sys.stdin]
     config = setup_config_parser(snap_pac_ini, parent_cmd, packages)
     snapper_configs = get_snapper_configs(snapper_conf_file)
     chroot = os.stat("/") != os.stat("/proc/1/root/.")
@@ -123,7 +139,11 @@ def main(snap_pac_ini, snapper_conf_file, args):
             description = get_description(args.type, config, snapper_config)
             pre_number = get_pre_number(args.type, prefile)
 
-            snapper_cmd = SnapperCmd(snapper_config, args.type, cleanup_algorithm, description, chroot, pre_number)
+            important = (check_important_commands(config, snapper_config, parent_cmd) or
+                         check_important_packages(config, snapper_config, packages))
+
+            snapper_cmd = SnapperCmd(snapper_config, args.type, cleanup_algorithm,
+                                     description, chroot, pre_number, important)
             num = snapper_cmd()
             logging.info(f"==> {snapper_config}: {num}")
 

tests/test_script.py

@@ -6,8 +6,8 @@ import os
 import pytest
 
 from scripts.snap_pac import (
-   SnapperCmd, get_pre_number, get_snapper_configs, main, setup_config_parser,
-   get_description
+   SnapperCmd, check_important_commands, check_important_packages, get_pre_number, get_snapper_configs,
+   main, setup_config_parser, get_description
 )
 
 
@@ -54,6 +54,11 @@ def prefile():
         SnapperCmd("root", "post", "number", "bar", True, 1234),
         "snapper --no-dbus --config root create --type post --cleanup-algorithm number --print-number"
         " --description \"bar\" --pre-number 1234"
+    ),
+    (
+        SnapperCmd("root", "post", "number", "bar", False, 1234, True),
+        "snapper --config root create --type post --cleanup-algorithm number --print-number"
+        " --description \"bar\" --userdata \"important=yes\" --pre-number 1234"
     )
 ])
 def test_snapper_cmd(snapper_cmd, actual_cmd):
@@ -84,7 +89,7 @@ def test_setup_config_parser(config):
         f.write("desc_limit = 3\n")
         f.write("post_description = a really long description\n")
         name = f.name
-    config2 = setup_config_parser(name, "foo", "bar")
+    config2 = setup_config_parser(name, "foo", ["bar"])
     assert config == config2
 
 
@@ -104,3 +109,25 @@ def test_no_prefile():
 @pytest.mark.parametrize("snapshot_type, description", [("pre", "foo"), ("post", "a r")])
 def test_get_description(snapshot_type, description, config):
     assert get_description(snapshot_type, config, "home") == description
+
+
+def test_important_commands():
+    parent_cmd = "pacman -Syu"
+    with tempfile.NamedTemporaryFile("w", delete=False) as f:
+        f.write("[DEFAULT]\n")
+        f.write("important_commands = [\"pacman -Syu\"]\n")
+        name = f.name
+    config = setup_config_parser(name, parent_cmd, ["bar"])
+    important = check_important_commands(config, "root", parent_cmd)
+    assert important
+
+
+def test_important_packages():
+    packages = ["bar", "linux", "vim"]
+    with tempfile.NamedTemporaryFile("w", delete=False) as f:
+        f.write("[DEFAULT]\n")
+        f.write("important_packages = [\"linux\"]\n")
+        name = f.name
+    config = setup_config_parser(name, "pacman -S", packages)
+    important = check_important_packages(config, "root", packages)
+    assert important