feat(ps): Add service filtering to ps command (#33)

README.md

@@ -407,7 +407,7 @@ Full `--help` output for each command. See the [Usage](#usage) table above for a
 ╰──────────────────────────────────────────────────────────────────────────────╯
 ╭─ Monitoring ─────────────────────────────────────────────────────────────────╮
 │ logs           Show service logs.                                            │
-│ ps             Show status of all services.                                  │
+│ ps             Show status of services.                                      │
 │ stats          Show overview statistics for hosts and services.              │
 ╰──────────────────────────────────────────────────────────────────────────────╯
 ╭─ Server ─────────────────────────────────────────────────────────────────────╮
@@ -904,11 +904,19 @@ Full `--help` output for each command. See the [Usage](#usage) table above for a
 <!-- ⚠️ This content is auto-generated by `markdown-code-runner`. -->
 ```yaml
 
- Usage: cf ps [OPTIONS]
+ Usage: cf ps [OPTIONS] [SERVICES]...
 
- Show status of all services.
+ Show status of services.
 
+ Without arguments: shows all services (same as --all). With service names:
+ shows only those services. With --host: shows services on that host.
+
+╭─ Arguments ──────────────────────────────────────────────────────────────────╮
+│   services      [SERVICES]...  Services to operate on                        │
+╰──────────────────────────────────────────────────────────────────────────────╯
 ╭─ Options ────────────────────────────────────────────────────────────────────╮
+│ --all     -a            Run on all services                                  │
+│ --host    -H      TEXT  Filter to services on this host                      │
 │ --config  -c      PATH  Path to config file                                  │
 │ --help    -h            Show this message and exit.                          │
 ╰──────────────────────────────────────────────────────────────────────────────╯

src/compose_farm/cli/common.py

@@ -144,17 +144,45 @@ def get_services(
     services: list[str],
     all_services: bool,
     config_path: Path | None,
+    *,
+    host: str | None = None,
+    default_all: bool = False,
 ) -> tuple[list[str], Config]:
     """Resolve service list and load config.
 
+    Handles three mutually exclusive selection methods:
+    - Explicit service names
+    - --all flag
+    - --host filter
+
+    Args:
+        services: Explicit service names
+        all_services: Whether --all was specified
+        config_path: Path to config file
+        host: Filter to services on this host
+        default_all: If True, default to all services when nothing specified (for ps)
+
     Supports "." as shorthand for the current directory name.
+
     """
+    validate_service_selection(services, all_services, host)
     config = load_config_or_exit(config_path)
 
+    if host is not None:
+        validate_host(config, host)
+        svc_list = [s for s in config.services if host in config.get_hosts(s)]
+        if not svc_list:
+            print_warning(f"No services configured for host [magenta]{host}[/]")
+            raise typer.Exit(0)
+        return svc_list, config
+
     if all_services:
         return list(config.services.keys()), config
+
     if not services:
-        print_error("Specify services or use [bold]--all[/]")
+        if default_all:
+            return list(config.services.keys()), config
+        print_error("Specify services or use [bold]--all[/] / [bold]--host[/]")
         raise typer.Exit(1)
 
     # Resolve "." to current directory name
@@ -286,6 +314,22 @@ def validate_host_for_service(cfg: Config, service: str, host: str) -> None:
         raise typer.Exit(1)
 
 
+def validate_service_selection(
+    services: list[str] | None,
+    all_services: bool,
+    host: str | None,
+) -> None:
+    """Validate that only one service selection method is used.
+
+    The three selection methods (explicit services, --all, --host) are mutually
+    exclusive. This ensures consistent behavior across all commands.
+    """
+    methods = sum([bool(services), all_services, host is not None])
+    if methods > 1:
+        print_error("Use only one of: service names, [bold]--all[/], or [bold]--host[/]")
+        raise typer.Exit(1)
+
+
 def run_host_operation(
     cfg: Config,
     svc_list: list[str],

src/compose_farm/cli/lifecycle.py

@@ -21,19 +21,16 @@ from compose_farm.cli.common import (
     maybe_regenerate_traefik,
     report_results,
     run_async,
-    run_host_operation,
 )
 from compose_farm.console import MSG_DRY_RUN, console, print_error, print_success
 from compose_farm.executor import run_on_services, run_sequential_on_services
 from compose_farm.operations import stop_orphaned_services, up_services
 from compose_farm.state import (
-    add_service_to_host,
     get_orphaned_services,
     get_service_host,
     get_services_needing_migration,
     get_services_not_in_state,
     remove_service,
-    remove_service_from_host,
 )
 
 
@@ -45,14 +42,7 @@ def up(
     config: ConfigOption = None,
 ) -> None:
     """Start services (docker compose up -d). Auto-migrates if host changed."""
-    svc_list, cfg = get_services(services or [], all_services, config)
-
-    # Per-host operation: run on specific host only
-    if host:
-        run_host_operation(cfg, svc_list, host, "up -d", "Starting", add_service_to_host)
-        return
-
-    # Normal operation: use up_services with migration logic
+    svc_list, cfg = get_services(services or [], all_services, config, host=host)
     results = run_async(up_services(cfg, svc_list, raw=True))
     maybe_regenerate_traefik(cfg, results)
     report_results(results)
@@ -72,7 +62,7 @@ def down(
     config: ConfigOption = None,
 ) -> None:
     """Stop services (docker compose down)."""
-    # Handle --orphaned flag
+    # Handle --orphaned flag (mutually exclusive with other selection methods)
     if orphaned:
         if services or all_services or host:
             print_error(
@@ -95,14 +85,7 @@ def down(
         report_results(results)
         return
 
-    svc_list, cfg = get_services(services or [], all_services, config)
-
-    # Per-host operation: run on specific host only
-    if host:
-        run_host_operation(cfg, svc_list, host, "down", "Stopping", remove_service_from_host)
-        return
-
-    # Normal operation
+    svc_list, cfg = get_services(services or [], all_services, config, host=host)
     raw = len(svc_list) == 1
     results = run_async(run_on_services(cfg, svc_list, "down", raw=raw))
 

src/compose_farm/cli/monitoring.py

@@ -20,9 +20,8 @@ from compose_farm.cli.common import (
     report_results,
     run_async,
     run_parallel_with_progress,
-    validate_host,
 )
-from compose_farm.console import console, print_error, print_warning
+from compose_farm.console import console
 from compose_farm.executor import run_command, run_on_services
 from compose_farm.state import get_services_needing_migration, group_services_by_host, load_state
 
@@ -127,22 +126,7 @@ def logs(
     config: ConfigOption = None,
 ) -> None:
     """Show service logs."""
-    if all_services and host is not None:
-        print_error("Cannot combine [bold]--all[/] and [bold]--host[/]")
-        raise typer.Exit(1)
-
-    cfg = load_config_or_exit(config)
-
-    # Determine service list based on options
-    if host is not None:
-        validate_host(cfg, host)
-        # Include services where host is in the list of configured hosts
-        svc_list = [s for s in cfg.services if host in cfg.get_hosts(s)]
-        if not svc_list:
-            print_warning(f"No services configured for host [magenta]{host}[/]")
-            return
-    else:
-        svc_list, cfg = get_services(services or [], all_services, config)
+    svc_list, cfg = get_services(services or [], all_services, config, host=host)
 
     # Default to fewer lines when showing multiple services
     many_services = all_services or host is not None or len(svc_list) > 1
@@ -156,11 +140,19 @@ def logs(
 
 @app.command(rich_help_panel="Monitoring")
 def ps(
+    services: ServicesArg = None,
+    all_services: AllOption = False,
+    host: HostOption = None,
     config: ConfigOption = None,
 ) -> None:
-    """Show status of all services."""
-    cfg = load_config_or_exit(config)
-    results = run_async(run_on_services(cfg, list(cfg.services.keys()), "ps"))
+    """Show status of services.
+
+    Without arguments: shows all services (same as --all).
+    With service names: shows only those services.
+    With --host: shows services on that host.
+    """
+    svc_list, cfg = get_services(services or [], all_services, config, host=host, default_all=True)
+    results = run_async(run_on_services(cfg, svc_list, "ps"))
     report_results(results)
 
 

tests/test_cli_logs.py

@@ -150,7 +150,7 @@ class TestLogsHostFilter:
         mock_run_async, _ = _mock_run_async_factory(["svc1", "svc2"])
 
         with (
-            patch("compose_farm.cli.monitoring.load_config_or_exit", return_value=cfg),
+            patch("compose_farm.cli.common.load_config_or_exit", return_value=cfg),
             patch("compose_farm.cli.monitoring.run_async", side_effect=mock_run_async),
             patch("compose_farm.cli.monitoring.run_on_services") as mock_run,
         ):
@@ -174,7 +174,7 @@ class TestLogsHostFilter:
         mock_run_async, _ = _mock_run_async_factory(["svc1", "svc2"])
 
         with (
-            patch("compose_farm.cli.monitoring.load_config_or_exit", return_value=cfg),
+            patch("compose_farm.cli.common.load_config_or_exit", return_value=cfg),
             patch("compose_farm.cli.monitoring.run_async", side_effect=mock_run_async),
             patch("compose_farm.cli.monitoring.run_on_services") as mock_run,
         ):