feat: add aurweb-config console script

This can be used to update config values for the entirety
of a config. When config values are set through this tool,
$AUR_CONFIG is overridden with a copy of the config file
with all sections and options found in $AUR_CONFIG
+ $AUR_CONFIG_DEFAULTS.

Signed-off-by: Kevin Morris <kevr@0cost.org>

aurweb/scripts/config.py

@@ -0,0 +1,61 @@
+"""
+Perform an action on the aurweb config.
+
+When AUR_CONFIG_IMMUTABLE is set, the `set` action is noop.
+"""
+import argparse
+import configparser
+import os
+import sys
+
+import aurweb.config
+
+
+def action_set(args):
+    # If AUR_CONFIG_IMMUTABLE is defined, skip out on config setting.
+    if os.environ.get("AUR_CONFIG_IMMUTABLE", 0):
+        return
+
+    if not args.value:
+        print("error: no value provided", file=sys.stderr)
+        return
+
+    try:
+        aurweb.config.replace_key(args.section, args.option, args.value)
+        aurweb.config.save()
+    except configparser.NoSectionError:
+        print("error: no section found", file=sys.stderr)
+
+
+def action_get(args):
+    try:
+        value = aurweb.config.get(args.section, args.option)
+        print(value)
+    except (configparser.NoSectionError):
+        print("error: no section found", file=sys.stderr)
+    except (configparser.NoOptionError):
+        print("error: no option found", file=sys.stderr)
+
+
+def parse_args():
+    fmt_cls = argparse.RawDescriptionHelpFormatter
+    actions = ["get", "set"]
+    parser = argparse.ArgumentParser(
+        description="aurweb configuration tool",
+        formatter_class=lambda prog: fmt_cls(prog=prog, max_help_position=80))
+    parser.add_argument("action", choices=actions, help="script action")
+    parser.add_argument("section", help="config section")
+    parser.add_argument("option", help="config option")
+    parser.add_argument("value", nargs="?", default=0,
+                        help="config option value")
+    return parser.parse_args()
+
+
+def main():
+    args = parse_args()
+    action = getattr(sys.modules[__name__], f"action_{args.action}")
+    return action(args)
+
+
+if __name__ == "__main__":
+    main()