refactor: extract Compose state parsing from shell

libexec/mcserver-kit/compose-state.py

@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+"""Classify Docker Compose's JSON container listing for the CLI and TUI."""
+
+import json
+import sys
+
+
+def classify(raw: str) -> str:
+    raw = raw.strip()
+    if not raw:
+        return "absent"
+
+    try:
+        parsed = json.loads(raw)
+    except json.JSONDecodeError:
+        try:
+            parsed = [json.loads(line) for line in raw.splitlines()]
+        except json.JSONDecodeError:
+            return "unavailable"
+
+    if isinstance(parsed, dict):
+        containers = [parsed]
+    elif isinstance(parsed, list) and all(isinstance(item, dict) for item in parsed):
+        containers = parsed
+    else:
+        return "unavailable"
+
+    if any(
+        item.get("Service") == "minecraft"
+        and str(item.get("State", "")).lower() == "running"
+        for item in containers
+    ):
+        return "running"
+    return "stopped" if containers else "absent"
+
+
+if __name__ == "__main__":
+    print(classify(sys.stdin.read()))

libexec/mcserver-kit/server-manager.sh

@@ -89,27 +89,7 @@ container_state() {
     printf 'unavailable\n'
     return
   fi
-  printf '%s\n' "$listing" | python3 -c '
-import json
-import sys
-
-data = sys.stdin.read().strip()
-if not data:
-    print("absent")
-    sys.exit()
-try:
-    containers = json.loads(data) if data.startswith("[") else [json.loads(line) for line in data.splitlines()]
-except (ValueError, TypeError):
-    print("unavailable")
-    sys.exit()
-minecraft = [c for c in containers if c.get("Service") == "minecraft"]
-if any(c.get("State", "").lower() == "running" for c in minecraft):
-    print("running")
-elif containers:
-    print("stopped")
-else:
-    print("absent")
-'
+  printf '%s\n' "$listing" | python3 "${SCRIPT_DIR}/compose-state.py"
 }
 
 server_state() {

tests/run-tests.sh

@@ -615,6 +615,17 @@ CONFIG
   assert_equal '600' "$(stat -c '%a' "$config_file")" 'config editor preserves restricted permissions'
 }
 
+test_compose_state_parser() {
+  local parser="${REPO_ROOT}/libexec/mcserver-kit/compose-state.py"
+  assert_equal 'absent' "$(printf '\n' | python3 "$parser")" 'empty Compose output means no containers'
+  assert_equal 'absent' "$(printf '[]\n' | python3 "$parser")" 'an empty Compose array means no containers'
+  assert_equal 'running' "$(printf '[{"Service":"minecraft","State":"running"}]\n' | python3 "$parser")" 'array output detects the running server'
+  assert_equal 'stopped' "$(printf '{"Service":"minecraft","State":"exited"}\n' | python3 "$parser")" 'object output detects a retained container'
+  assert_equal 'running' "$(printf '%s\n%s\n' '{"Service":"playit","State":"running"}' '{"Service":"minecraft","State":"running"}' | python3 "$parser")" 'newline-delimited output finds the Minecraft container'
+  assert_equal 'unavailable' "$(printf '{invalid\n' | python3 "$parser")" 'malformed Compose JSON is not mistaken for no container'
+  assert_equal 'unavailable' "$(printf '123\n' | python3 "$parser")" 'unexpected Compose JSON shapes are rejected'
+}
+
 test_server_management() {
   local temp_dir="$1"
   local root="${temp_dir}/server-management/servers"
@@ -957,6 +968,7 @@ main() {
   test_setup_command "$TEST_TEMP_DIR"
   test_reset_command "$TEST_TEMP_DIR"
   test_config_value_editor "$TEST_TEMP_DIR"
+  test_compose_state_parser
   test_server_management "$TEST_TEMP_DIR"
   test_server_property_editor "$TEST_TEMP_DIR"
   test_property_import_and_explorer "$TEST_TEMP_DIR"