Add docker_compose_compat setting

Signed-off-by: Uosis <uosisl+github@gmail.com>

docs/Extensions.md

@@ -139,6 +139,24 @@ The options to the network modes are passed to the `--network` option of the `po
 as-is.
 
 
+## Docker Compose Compatibility
+
+podman-compose aims to be compatible with docker-compose, but there are some differences in
+behavior and features. The following sections describe how to enable compatibility with docker-compose
+and how to handle some of the differences.
+
+Compatibility settings can either be set explicitly as described below, or by setting the `docker_compose_compat` meta
+settings to `true` under the global `x-podman` key:
+
+```yaml
+x-podman:
+    docker_compose_compat: true
+```
+
+This will enable all compatibility settings described below, and is equivalent to setting each of them to `true`.
+
+This setting can also be changed by setting the `PODMAN_COMPOSE_DOCKER_COMPOSE_COMPAT` environment variable.
+
 ## Compatibility of name separators between docker-compose and podman-compose
 
 Currently, podman-compose is using underscores (`_` character) as a separator in names of

newsfragments/docker-compose-compat.feature

@@ -0,0 +1 @@
+- Add new docker_compose_compat x-podman meta setting to enable all Docker Compose compatibility settings

podman_compose.py

@@ -1957,6 +1957,7 @@ COMPOSE_DEFAULT_LS = [
 
 class PodmanCompose:
     class XPodmanSettingKey(Enum):
+        DOCKER_COMPOSE_COMPAT = "docker_compose_compat"
         DEFAULT_NET_NAME_COMPAT = "default_net_name_compat"
         DEFAULT_NET_BEHAVIOR_COMPAT = "default_net_behavior_compat"
         NAME_SEPARATOR_COMPAT = "name_separator_compat"
@@ -2127,6 +2128,20 @@ class PodmanCompose:
                     ", ".join(known_keys.keys()),
                 )
 
+        # If Docker Compose compatibility is enabled, set compatibility settings
+        # that are not explicitly set already.
+        if self.x_podman.get(PodmanCompose.XPodmanSettingKey.DOCKER_COMPOSE_COMPAT, False):
+
+            def set_if_not_already_set(key: PodmanCompose.XPodmanSettingKey, value: bool) -> None:
+                if key not in self.x_podman:
+                    self.x_podman[key] = value
+
+            set_if_not_already_set(
+                PodmanCompose.XPodmanSettingKey.DEFAULT_NET_BEHAVIOR_COMPAT, True
+            )
+            set_if_not_already_set(PodmanCompose.XPodmanSettingKey.NAME_SEPARATOR_COMPAT, True)
+            set_if_not_already_set(PodmanCompose.XPodmanSettingKey.IN_POD, False)
+
     def _parse_compose_file(self) -> None:
         args = self.global_args
         # cmd = args.command

tests/integration/in_pod/test_podman_compose_in_pod.py

@@ -467,6 +467,57 @@ class TestPodmanComposeInPod(unittest.TestCase, RunSubprocessMixin):
             # can not actually find this pod because it was not created
             self.run_subprocess_assert_returncode(command_rm_pod, 1)
 
+    def test_x_podman_in_pod_not_exists_command_line_in_pod_not_exists_docker_compat(self) -> None:
+        """
+        Test that podman-compose will not create a pod when docker compat is requested.
+        """
+        command_up = [
+            "python3",
+            os.path.join(base_path(), "podman_compose.py"),
+            "-f",
+            os.path.join(
+                base_path(),
+                "tests",
+                "integration",
+                "in_pod",
+                "custom_x-podman_not_exists",
+                "docker-compose.yml",
+            ),
+            "up",
+            "-d",
+        ]
+
+        down_cmd = [
+            "python3",
+            podman_compose_path(),
+            "-f",
+            os.path.join(
+                base_path(),
+                "tests",
+                "integration",
+                "in_pod",
+                "custom_x-podman_not_exists",
+                "docker-compose.yml",
+            ),
+            "down",
+        ]
+
+        env = {
+            "PODMAN_COMPOSE_DOCKER_COMPOSE_COMPAT": "1",
+        }
+
+        try:
+            self.run_subprocess_assert_returncode(
+                command_up, failure_exitcode_when_rootful(), env=env
+            )
+
+        finally:
+            self.run_subprocess_assert_returncode(down_cmd, env=env)
+
+            command_rm_pod = ["podman", "pod", "rm", "pod_custom_x-podman_not_exists"]
+            # can not actually find this pod because it was not created
+            self.run_subprocess_assert_returncode(command_rm_pod, 1)
+
     def test_x_podman_in_pod_not_exists_command_line_in_pod_not_exists_env_var(self) -> None:
         """
         Test that podman-compose will not create a pod when env var is set.

tests/integration/name_separator_compat/test_podman_compose_name_separator_compat.py

@@ -14,6 +14,7 @@ class TestComposeNameSeparatorCompat(unittest.TestCase, RunSubprocessMixin):
     @parameterized.expand([
         ('default', {}, '_'),
         ('default', {'PODMAN_COMPOSE_NAME_SEPARATOR_COMPAT': '1'}, '-'),
+        ('default', {'PODMAN_COMPOSE_DOCKER_COMPOSE_COMPAT': '1'}, '-'),
         ('compat', {}, '-'),
         ('compat', {'PODMAN_COMPOSE_NAME_SEPARATOR_COMPAT': '1'}, '-'),
         ('compat', {'PODMAN_COMPOSE_NAME_SEPARATOR_COMPAT': '0'}, '_'),