Refactor container exclude labels

docker_custodian/docker_gc.py

@@ -13,6 +13,7 @@ import docker
 import docker.errors
 import requests.exceptions
 
+from collections import namedtuple
 from docker_custodian.args import timedelta_type
 from docker.utils import kwargs_from_env
 
@@ -22,6 +23,8 @@ log = logging.getLogger(__name__)
 # This seems to be something docker uses for a null/zero date
 YEAR_ZERO = "0001-01-01T00:00:00Z"
 
+ExcludeLabel = namedtuple('ExcludeLabel', ['key', 'value'])
+
 
 def cleanup_containers(
     client,
@@ -59,8 +62,11 @@ def cleanup_containers(
 
 
 def filter_excluded_containers(containers, exclude_container_labels):
+    if not exclude_container_labels:
+        return containers
+
     def include_container(container):
-        if exclude_container_labels and should_exclude_container_with_labels(
+        if should_exclude_container_with_labels(
             container,
             exclude_container_labels,
         ):
@@ -70,22 +76,20 @@ def filter_excluded_containers(containers, exclude_container_labels):
 
 
 def should_exclude_container_with_labels(container, exclude_container_labels):
-    for exclude_container_label in exclude_container_labels:
-        split_exclude_label = exclude_container_label.split('=', 1)
-        if len(split_exclude_label) == 2:
-            exclude_key, exclude_value = split_exclude_label
+    for exclude_label in exclude_container_labels:
+        if exclude_label.value:
             matching_keys = fnmatch.filter(
-                container['Labels'].keys(), exclude_key
+                container['Labels'].keys(),
+                exclude_label.key,
             )
             label_values_to_check = [
                 container['Labels'][matching_key]
                 for matching_key in matching_keys
             ]
-            if fnmatch.filter(label_values_to_check, exclude_value):
+            if fnmatch.filter(label_values_to_check, exclude_label.value):
                 return True
         else:
-            exclude_key = split_exclude_label[0]
-            if fnmatch.filter(container['Labels'].keys(), exclude_key):
+            if fnmatch.filter(container['Labels'].keys(), exclude_label.key):
                 return True
     return False
 
@@ -261,6 +265,24 @@ def build_exclude_set(image_tags, exclude_file):
     return exclude_set
 
 
+def format_exclude_labels(exclude_label_args):
+    exclude_labels = []
+    for exclude_label_arg in exclude_label_args:
+        split_exclude_label = exclude_label_arg.split('=', 1)
+        exclude_label_key = split_exclude_label[0]
+        if len(split_exclude_label) == 2:
+            exclude_label_value = split_exclude_label[1]
+        else:
+            exclude_label_value = None
+        exclude_labels.append(
+            ExcludeLabel(
+                key=exclude_label_key,
+                value=exclude_label_value,
+            )
+        )
+    return exclude_labels
+
+
 def main():
     logging.basicConfig(
         level=logging.INFO,
@@ -272,12 +294,16 @@ def main():
                               timeout=args.timeout,
                               **kwargs_from_env())
 
+    exclude_container_labels = format_exclude_labels(
+        args.exclude_container_label
+    )
+
     if args.max_container_age:
         cleanup_containers(
             client,
             args.max_container_age,
             args.dry_run,
-            args.exclude_container_label,
+            exclude_container_labels,
         )
 
     if args.max_image_age:
@@ -325,7 +351,7 @@ def get_args(args=None):
              "image tag per line.")
     parser.add_argument(
         '--exclude-container-label',
-        action='append',
+        action='append', type=str, default=[],
         help="Never remove containers with this label key or label key=value")
 
     return parser.parse_args(args=args)

tests/docker_gc_test.py

@@ -78,13 +78,18 @@ def test_filter_excluded_containers():
     ]
     result = docker_gc.filter_excluded_containers(mock_containers, None)
     assert mock_containers == list(result)
-    exclude_labels = ['too', 'foo']
+    exclude_labels = [
+        docker_gc.ExcludeLabel(key='too', value=None),
+        docker_gc.ExcludeLabel(key='foo', value=None),
+    ]
     result = docker_gc.filter_excluded_containers(
         mock_containers,
         exclude_labels,
     )
     assert [mock_containers[0], mock_containers[2]] == list(result)
-    exclude_labels = ['too*=lol']
+    exclude_labels = [
+        docker_gc.ExcludeLabel(key='too*', value='lol'),
+    ]
     result = docker_gc.filter_excluded_containers(
         mock_containers,
         exclude_labels,
@@ -482,6 +487,19 @@ def test_build_exclude_set():
     assert exclude_set == expected
 
 
+def test_format_exclude_labels():
+    exclude_label_args = [
+        'voo*',
+        'doo=poo',
+    ]
+    expected = [
+        docker_gc.ExcludeLabel(key='voo*', value=None),
+        docker_gc.ExcludeLabel(key='doo', value='poo'),
+    ]
+    exclude_labels = docker_gc.format_exclude_labels(exclude_label_args)
+    assert expected == exclude_labels
+
+
 def test_build_exclude_set_empty():
     exclude_set = docker_gc.build_exclude_set(None, None)
     assert exclude_set == set()
@@ -500,5 +518,6 @@ def test_main(mock_client):
                 max_container_age=200,
                 exclude_image=[],
                 exclude_image_file=None,
+                exclude_container_label=[],
             )
             docker_gc.main()