fix(docker): surface enumeration failures

bot_bottle/backend/docker/compose.py

@@ -52,19 +52,20 @@ def slug_from_compose_project(project: str) -> str:
 
 
 def list_compose_projects(
-    *, include_stopped: bool = True, warn_on_error: bool = True,
+    *,
+    include_stopped: bool = True,
+    warn_on_error: bool = True,
+    raise_on_error: bool = False,
 ) -> list[str]:
     """All compose project names starting with `bot-bottle-`.
     `include_stopped=True` (default) runs `docker compose ls --all`
     so exited projects appear too; pass False to get only projects
     with at least one running container.
 
-    Returns [] on docker daemon errors or malformed output rather
-    than raising — callers should treat the empty list as "no
-    projects discoverable", not "no projects exist". `warn_on_error`
-    stays true for explicit operator commands like cleanup, but active
-    discovery paths set it false so dashboard refreshes don't spam
-    stderr while Docker Desktop is stopped."""
+    Best-effort callers get ``[]`` on Docker errors or malformed output.
+    Enumeration callers pass ``raise_on_error=True`` so a failed query is not
+    reported as an authoritative empty result.
+    """
     argv = ["docker", "compose", "ls", "--format", "json"]
     if include_stopped:
         argv.insert(3, "--all")
@@ -72,19 +73,25 @@ def list_compose_projects(
         result = subprocess.run(
             argv, capture_output=True, text=True, check=False,
         )
-    except FileNotFoundError:
-        # docker binary not on PATH — same shape as a daemon-down
-        # error from the caller's POV: no projects discoverable.
+    except FileNotFoundError as exc:
+        if raise_on_error:
+            raise RuntimeError("docker compose ls failed: docker not found") from exc
         return []
     if result.returncode != 0:
+        message = f"docker compose ls failed: {result.stderr.strip()}"
+        if raise_on_error:
+            raise RuntimeError(message)
         if warn_on_error:
-            warn(f"docker compose ls failed: {result.stderr.strip()}")
+            warn(message)
         return []
     try:
         projects = json.loads(result.stdout or "[]")
     except json.JSONDecodeError as e:
+        message = f"docker compose ls returned malformed JSON: {e}"
+        if raise_on_error:
+            raise RuntimeError(message) from e
         if warn_on_error:
-            warn(f"docker compose ls returned malformed JSON: {e}")
+            warn(message)
         return []
     names: list[str] = []
     for p in projects:
@@ -97,7 +104,10 @@ def list_compose_projects(
 
 
 def list_active_slugs(
-    *, include_stopped: bool = False, warn_on_error: bool = True,
+    *,
+    include_stopped: bool = False,
+    warn_on_error: bool = True,
+    raise_on_error: bool = False,
 ) -> list[str]:
     """Slugs (project name minus prefix) of currently-running
     bottles. Used by the dashboard's operator-edit verbs to choose
@@ -108,6 +118,7 @@ def list_active_slugs(
             for p in list_compose_projects(
                 include_stopped=include_stopped,
                 warn_on_error=warn_on_error,
+                raise_on_error=raise_on_error,
             )
         ) if slug
     )

bot_bottle/backend/docker/enumerate.py

@@ -1,9 +1,8 @@
 """Active-agent enumeration for the docker backend.
 
 Returns `ActiveAgent` records the CLI `active` command and the
-dashboard agents pane consume. Empty when docker isn't reachable
-— gated by `has_backend('docker')` at the cross-backend caller
-so this module trusts that docker is available when called.
+dashboard agents pane consume. Docker query failures raise rather
+than masquerading as an authoritative empty result.
 
 The parser (`_parse_services_by_project`) is exposed for direct
 unit testing; the docker `docker ps` invocation is in
@@ -19,11 +18,12 @@ from .compose import compose_project_name, list_active_slugs
 
 
 def enumerate_active() -> list[ActiveAgent]:
-    """All currently-running docker-backed agents. Caller is
-    responsible for gating on `has_backend('docker')` if it
-    matters; if docker is missing the `docker ps` call below
-    returns an empty list silently."""
-    slugs = list_active_slugs(include_stopped=False, warn_on_error=False)
+    """All currently-running docker-backed agents."""
+    slugs = list_active_slugs(
+        include_stopped=False,
+        warn_on_error=False,
+        raise_on_error=True,
+    )
     if not slugs:
         return []
     services_by_project = _query_services_by_project()
@@ -74,8 +74,8 @@ def _query_services_by_project() -> dict[str, set[str]]:
             ],
             capture_output=True, text=True, check=False,
         )
-    except FileNotFoundError:
-        return {}
+    except FileNotFoundError as exc:
+        raise RuntimeError("docker ps failed: docker not found") from exc
     if r.returncode != 0:
-        return {}
+        raise RuntimeError(f"docker ps failed: {r.stderr.strip()}")
     return _parse_services_by_project(r.stdout or "")

tests/unit/test_compose.py

@@ -69,6 +69,19 @@ class TestComposeProjectListing(unittest.TestCase):
             self.assertEqual([], list_active_slugs(warn_on_error=False))
         warn.assert_not_called()
 
+    def test_compose_ls_error_can_be_raised_for_enumeration(self):
+        with mock.patch(
+            "bot_bottle.backend.docker.compose.subprocess.run",
+            return_value=subprocess.CompletedProcess(
+                args=["docker"], returncode=1, stdout="", stderr="no daemon",
+            ),
+        ):
+            with self.assertRaisesRegex(RuntimeError, "no daemon"):
+                list_active_slugs(
+                    warn_on_error=False,
+                    raise_on_error=True,
+                )
+
 
 if __name__ == "__main__":
     unittest.main()

tests/unit/test_docker_enumerate_active.py

@@ -19,9 +19,11 @@ of issue #77 — the dashboard now delegates to this layer.
 
 from __future__ import annotations
 
+import subprocess
 import tempfile
 import unittest
 from pathlib import Path
+from unittest.mock import patch
 
 from tests.unit import use_bottle_root
 from bot_bottle import bottle_state
@@ -72,6 +74,18 @@ class TestParseServicesByProject(unittest.TestCase):
         self.assertEqual({"bot-bottle-dev-abc": {"egress"}}, out)
 
 
+class TestQueryServicesByProject(unittest.TestCase):
+    def test_docker_ps_failure_is_not_an_empty_result(self):
+        with patch(
+            "bot_bottle.backend.docker.enumerate.subprocess.run",
+            return_value=subprocess.CompletedProcess(
+                args=["docker"], returncode=1, stdout="", stderr="daemon down",
+            ),
+        ):
+            with self.assertRaisesRegex(RuntimeError, "daemon down"):
+                _enumerate._query_services_by_project()
+
+
 class _FakeHomeMixin:
     def _setup_fake_home(self) -> None:
         self._tmp = tempfile.TemporaryDirectory(prefix="enum-active.")