GRM-13: feat: replace print() with stdlib logging module

- Create logging_config.py with get_logger() providing dual handlers:
  - Console handler (stderr) controlled by GRM_LOG_LEVEL env var (default INFO)
  - File handler (~/.local/state/grm/logs/grm.log) capturing everything at DEBUG
- Replace all print() calls in executor.py and report.py with logger.info()/error()
- Add error logging before raising AnsibleError in executor.run()
- Add GRM_LOG_LEVEL to README configuration table and logging documentation
- Update all unit tests to mock logger instead of using capsys
- 114 tests, 100% coverage, pyright clean, ruff clean

README.md

@@ -152,6 +152,18 @@ Optional: If `GITEA_ADMIN_TOKEN` is set, the installer will also query the Gitea
 
 ### View Logs
 
+**GRM application logs** (Python CLI output):
+
+```bash
+# Application log file (all messages including DEBUG)
+cat ~/.local/state/grm/logs/grm.log
+
+# Enable debug logging in the current session
+GRM_LOG_LEVEL=DEBUG grm install 192.168.1.10 --user ubuntu --name prod-runner
+```
+
+**Runner logs** (on the remote host):
+
 ```bash
 # Binary mode logs (via systemd template unit)
 sudo journalctl -u gitea-runner@<name> -f
@@ -160,6 +172,15 @@ sudo journalctl -u gitea-runner@<name> -f
 docker logs gitea-runner-<name> -f
 ```
 
+The GRM application writes two parallel log streams:
+
+| Destination | Level | Content |
+|-------------|-------|---------|
+| Console (stderr) | `GRM_LOG_LEVEL` (default: INFO) | User-facing messages and operation reports |
+| `~/.local/state/grm/logs/grm.log` | DEBUG | All messages with timestamps and severity |
+
+Set `GRM_LOG_LEVEL` to one of `DEBUG`, `INFO`, `WARNING`, `ERROR`, or `CRITICAL` to control console verbosity. The log file always captures everything at DEBUG level.
+
 ## Architecture
 
 GRM consists of two layers:
@@ -212,6 +233,7 @@ All tunable values are exposed as Ansible variables in `ansible/roles/gitea-runn
 | `gitea_runner_container_label` | `gitea-runner=true` | Container label |
 | `docker_gpg_key_path` | `/etc/apt/keyrings/docker.asc` | Docker GPG key path |
 | `GRM_LANG` | `en` | CLI language: `en`, `bg`, `de`, `ru`, `zh` |
+| `GRM_LOG_LEVEL` | `INFO` | Console verbosity: `DEBUG`, `INFO`, `WARNING`, `ERROR`, `CRITICAL` |
 
 Override any variable by passing it to the CLI with `--extra-vars` or by setting it in your Ansible inventory.
 

src/gitea_runner_manager/executor.py

@@ -10,6 +10,7 @@ from pathlib import Path
 
 from .exceptions import AnsibleError
 from .i18n import _
+from .logging_config import get_logger
 
 
 class AnsibleExecutor:
@@ -17,31 +18,32 @@ class AnsibleExecutor:
 
     def __init__(self, log_dir: Path | None = None) -> None:
         self._log_dir = log_dir or Path.home() / ".local" / "state" / "grm" / "logs"
+        self._logger = get_logger()
 
     def run(self, cmd: list[str], description: str = "") -> None:
         """Run an Ansible command, redirecting output to a log file."""
         log_file = self._prepare_log(cmd)
         desc = description or _("Running Ansible playbook")
 
-        print(f"[GRM] {desc}")
-        print(f"[GRM] {_('Full log: {log_file}', log_file=log_file)}")
+        self._logger.info(desc)
+        self._logger.info(_("Full log: {log_file}", log_file=log_file))
 
         returncode = self._stream(cmd, log_file)
 
         if returncode != 0:
-            raise AnsibleError(
-                _(
-                    "Ansible failed with exit code {code}. See full log: {log_file}",
-                    code=returncode,
-                    log_file=log_file,
-                )
+            msg = _(
+                "Ansible failed with exit code {code}. See full log: {log_file}",
+                code=returncode,
+                log_file=log_file,
             )
+            self._logger.error(msg)
+            raise AnsibleError(msg)
 
         status = self._extract_status(log_file)
         if status:
-            print(f"[GRM] {status}")
+            self._logger.info(status)
 
-        print(f"[GRM] {_('Done. See full log: {log_file}', log_file=log_file)}")
+        self._logger.info(_("Done. See full log: {log_file}", log_file=log_file))
 
     def _prepare_log(self, cmd: list[str]) -> Path:
         """Create a log file with header."""

src/gitea_runner_manager/logging_config.py

@@ -0,0 +1,46 @@
+"""GRM logging configuration using the standard library."""
+
+from __future__ import annotations
+
+import logging
+import os
+from pathlib import Path
+
+
+def get_logger(name: str = "grm") -> logging.Logger:
+    """Return a configured logger for GRM.
+
+    Console output respects ``GRM_LOG_LEVEL`` (default: INFO).
+    All messages are also written to ``~/.local/state/grm/logs/grm.log``.
+    """
+    logger = logging.getLogger(name)
+    if logger.handlers:
+        return logger
+
+    logger.setLevel(logging.DEBUG)
+
+    # Console handler — user-controlled level
+    console = logging.StreamHandler()
+    console.setLevel(_level_from_env(os.getenv("GRM_LOG_LEVEL", "INFO")))
+    console.setFormatter(logging.Formatter("[GRM] %(message)s"))
+    logger.addHandler(console)
+
+    # File handler — captures everything including DEBUG
+    log_dir = Path.home() / ".local" / "state" / "grm" / "logs"
+    log_dir.mkdir(parents=True, exist_ok=True)
+    file_handler = logging.FileHandler(log_dir / "grm.log")
+    file_handler.setLevel(logging.DEBUG)
+    file_handler.setFormatter(logging.Formatter("%(asctime)s %(levelname)s %(name)s: %(message)s"))
+    logger.addHandler(file_handler)
+
+    return logger
+
+
+def _level_from_env(value: str | None) -> int:
+    """Map a level name to a logging level constant."""
+    if not value:
+        return logging.INFO
+    try:
+        return getattr(logging, value.upper())
+    except AttributeError:
+        return logging.INFO

src/gitea_runner_manager/report.py

@@ -6,6 +6,7 @@ from collections.abc import Generator
 from contextlib import contextmanager
 
 from .i18n import _
+from .logging_config import get_logger
 
 
 class Step:
@@ -56,14 +57,15 @@ def track_steps() -> Generator[StepTracker, None, None]:
 
 def _print_report(steps: list[Step]) -> None:
     """Print a translated operation report to stdout."""
+    logger = get_logger()
     icons = {
         "completed": "✓",
         "failed": "✗",
         "pending": "○",
         "in_progress": "◌",
     }
-    print(f"[GRM] {_('=== Operation Report ===')}")
+    logger.info(_("=== Operation Report ==="))
     for step in steps:
         icon = icons.get(step.status, "?")
         status_label = _(step.status)
-        print(f"[GRM]   {icon} {step.name} ({status_label})")
+        logger.info(f"  {icon} {step.name} ({status_label})")

tests/unit/test_executor.py

@@ -20,31 +20,40 @@ def _mock_popen_process(returncode: int = 0) -> MagicMock:
 
 
 class TestAnsibleExecutorRun:
-    def test_run_success(self, tmp_path: Path, capsys: pytest.CaptureFixture[str]) -> None:
-        executor = AnsibleExecutor(log_dir=tmp_path)
-        with patch("subprocess.Popen") as mock_popen, patch("builtins.open", mock_open()):
-            mock_popen.return_value = _mock_popen_process(returncode=0)
-            executor.run(["echo", "hello"], description="Test run")
+    def test_run_success(self, tmp_path: Path) -> None:
+        mock_logger = MagicMock()
+        with patch("gitea_runner_manager.executor.get_logger", return_value=mock_logger):
+            executor = AnsibleExecutor(log_dir=tmp_path)
+            with patch("subprocess.Popen") as mock_popen, patch("builtins.open", mock_open()):
+                mock_popen.return_value = _mock_popen_process(returncode=0)
+                executor.run(["echo", "hello"], description="Test run")
 
-        captured = capsys.readouterr()
-        assert "[GRM] Test run" in captured.out
-        assert "[GRM] Done" in captured.out
+        messages = [call.args[0] for call in mock_logger.info.call_args_list]
+        assert any("Test run" in msg for msg in messages)
+        assert any("Done" in msg for msg in messages)
 
     def test_run_failure(self, tmp_path: Path) -> None:
-        executor = AnsibleExecutor(log_dir=tmp_path)
-        with patch("subprocess.Popen") as mock_popen, patch("builtins.open", mock_open()):
-            mock_popen.return_value = _mock_popen_process(returncode=1)
-            with pytest.raises(AnsibleError, match="exit code 1"):
-                executor.run(["false"], description="Test run")
+        mock_logger = MagicMock()
+        with patch("gitea_runner_manager.executor.get_logger", return_value=mock_logger):
+            executor = AnsibleExecutor(log_dir=tmp_path)
+            with patch("subprocess.Popen") as mock_popen, patch("builtins.open", mock_open()):
+                mock_popen.return_value = _mock_popen_process(returncode=1)
+                with pytest.raises(AnsibleError, match="exit code 1"):
+                    executor.run(["false"], description="Test run")
 
-    def test_run_default_description(self, tmp_path: Path, capsys: pytest.CaptureFixture[str]) -> None:
-        executor = AnsibleExecutor(log_dir=tmp_path)
-        with patch("subprocess.Popen") as mock_popen, patch("builtins.open", mock_open()):
-            mock_popen.return_value = _mock_popen_process(returncode=0)
-            executor.run(["echo", "hello"])
+        assert mock_logger.error.called
+        assert "exit code 1" in mock_logger.error.call_args[0][0]
 
-        captured = capsys.readouterr()
-        assert "[GRM] Running Ansible playbook" in captured.out
+    def test_run_default_description(self, tmp_path: Path) -> None:
+        mock_logger = MagicMock()
+        with patch("gitea_runner_manager.executor.get_logger", return_value=mock_logger):
+            executor = AnsibleExecutor(log_dir=tmp_path)
+            with patch("subprocess.Popen") as mock_popen, patch("builtins.open", mock_open()):
+                mock_popen.return_value = _mock_popen_process(returncode=0)
+                executor.run(["echo", "hello"])
+
+        messages = [call.args[0] for call in mock_logger.info.call_args_list]
+        assert any("Running Ansible playbook" in msg for msg in messages)
 
     def test_run_with_stdout_lines(self, tmp_path: Path) -> None:
         executor = AnsibleExecutor(log_dir=tmp_path)
@@ -60,20 +69,22 @@ class TestAnsibleExecutorRun:
             handle.write.assert_any_call("line1\n")
             handle.write.assert_any_call("line2\n")
 
-    def test_run_extracts_status(self, tmp_path: Path, capsys: pytest.CaptureFixture[str]) -> None:
-        executor = AnsibleExecutor(log_dir=tmp_path)
+    def test_run_extracts_status(self, tmp_path: Path) -> None:
+        mock_logger = MagicMock()
         log_content = (
             "TASK [gitea-runner : Report runner status]\n"
             "ok: [127.0.0.1] => {\n"
             '    "msg": "Runner \'127.0.0.1\' is installed and running."\n'
             "}\n"
         )
-        with patch("subprocess.Popen") as mock_popen, patch("builtins.open", mock_open(read_data=log_content)):
-            mock_popen.return_value = _mock_popen_process(returncode=0)
-            executor.run(["echo", "hello"], description="Test run")
+        with patch("gitea_runner_manager.executor.get_logger", return_value=mock_logger):
+            executor = AnsibleExecutor(log_dir=tmp_path)
+            with patch("subprocess.Popen") as mock_popen, patch("builtins.open", mock_open(read_data=log_content)):
+                mock_popen.return_value = _mock_popen_process(returncode=0)
+                executor.run(["echo", "hello"], description="Test run")
 
-        captured = capsys.readouterr()
-        assert "Runner '127.0.0.1' is installed and running" in captured.out
+        messages = [call.args[0] for call in mock_logger.info.call_args_list]
+        assert any("Runner '127.0.0.1' is installed and running" in msg for msg in messages)
 
 
 class TestAnsibleExecutorExtractStatus:
@@ -129,32 +140,34 @@ class TestAnsibleExecutorPrepareLog:
 
 
 class TestAnsibleExecutorTranslation:
-    def test_run_translated(self, tmp_path: Path, capsys: pytest.CaptureFixture[str]) -> None:
-        executor = AnsibleExecutor(log_dir=tmp_path)
+    def test_run_translated(self, tmp_path: Path) -> None:
+        mock_logger = MagicMock()
         with (
             patch.dict(os.environ, {"GRM_LANG": "de"}),
-            patch("subprocess.Popen") as mock_popen,
-            patch("builtins.open", mock_open()),
+            patch("gitea_runner_manager.executor.get_logger", return_value=mock_logger),
         ):
-            mock_popen.return_value = _mock_popen_process(returncode=0)
-            executor.run(["echo", "hello"])  # use default description to test translation
+            executor = AnsibleExecutor(log_dir=tmp_path)
+            with patch("subprocess.Popen") as mock_popen, patch("builtins.open", mock_open()):
+                mock_popen.return_value = _mock_popen_process(returncode=0)
+                executor.run(["echo", "hello"])  # use default description to test translation
 
-        captured = capsys.readouterr()
-        assert "Ansible-Playbook wird ausgeführt" in captured.out
-        assert "Fertig" in captured.out
+        messages = [call.args[0] for call in mock_logger.info.call_args_list]
+        assert any("Ansible-Playbook wird ausgeführt" in msg for msg in messages)
+        assert any("Fertig" in msg for msg in messages)
 
-    def test_unsupported_lang_fallback(self, tmp_path: Path, capsys: pytest.CaptureFixture[str]) -> None:
-        executor = AnsibleExecutor(log_dir=tmp_path)
+    def test_unsupported_lang_fallback(self, tmp_path: Path) -> None:
+        mock_logger = MagicMock()
         with (
             patch.dict(os.environ, {"GRM_LANG": "xx"}),
-            patch("subprocess.Popen") as mock_popen,
-            patch("builtins.open", mock_open()),
+            patch("gitea_runner_manager.executor.get_logger", return_value=mock_logger),
         ):
-            mock_popen.return_value = _mock_popen_process(returncode=0)
-            executor.run(["echo", "hello"])
+            executor = AnsibleExecutor(log_dir=tmp_path)
+            with patch("subprocess.Popen") as mock_popen, patch("builtins.open", mock_open()):
+                mock_popen.return_value = _mock_popen_process(returncode=0)
+                executor.run(["echo", "hello"])
 
-        captured = capsys.readouterr()
-        assert "[GRM] Running Ansible playbook" in captured.out  # English fallback
+        messages = [call.args[0] for call in mock_logger.info.call_args_list]
+        assert any("Running Ansible playbook" in msg for msg in messages)  # English fallback
 
 
 class TestAnsibleExecutorAdHoc:

tests/unit/test_logging_config.py

@@ -0,0 +1,88 @@
+"""Unit tests for logging configuration."""
+
+from __future__ import annotations
+
+import logging
+from collections.abc import Generator
+from pathlib import Path
+from unittest.mock import patch
+
+import pytest
+
+from gitea_runner_manager.logging_config import _level_from_env, get_logger
+
+
+@pytest.fixture(autouse=True)
+def _cleanup_loggers() -> Generator[None, None, None]:
+    """Remove test loggers after each test to prevent state leakage."""
+    yield
+    for name in list(logging.Logger.manager.loggerDict.keys()):
+        if name.startswith("test_"):
+            logger = logging.getLogger(name)
+            logger.handlers.clear()
+            del logging.Logger.manager.loggerDict[name]
+
+
+class TestLevelFromEnv:
+    def test_none_defaults_to_info(self) -> None:
+        assert _level_from_env(None) == logging.INFO
+
+    def test_empty_string_defaults_to_info(self) -> None:
+        assert _level_from_env("") == logging.INFO
+
+    def test_valid_levels(self) -> None:
+        assert _level_from_env("debug") == logging.DEBUG
+        assert _level_from_env("DEBUG") == logging.DEBUG
+        assert _level_from_env("warning") == logging.WARNING
+        assert _level_from_env("error") == logging.ERROR
+        assert _level_from_env("critical") == logging.CRITICAL
+
+    def test_invalid_fallback_to_info(self) -> None:
+        assert _level_from_env("foo") == logging.INFO
+        assert _level_from_env("VERBOSE") == logging.INFO
+
+
+class TestGetLogger:
+    def test_returns_logger(self, tmp_path: Path) -> None:
+        with patch("gitea_runner_manager.logging_config.Path.home", return_value=tmp_path):
+            logger = get_logger("test_returns_logger")
+
+        assert isinstance(logger, logging.Logger)
+        assert logger.name == "test_returns_logger"
+        assert len(logger.handlers) == 2  # console + file
+
+    def test_caches_same_instance(self, tmp_path: Path) -> None:
+        with patch("gitea_runner_manager.logging_config.Path.home", return_value=tmp_path):
+            logger1 = get_logger("test_caches_same")
+            logger2 = get_logger("test_caches_same")
+
+        assert logger1 is logger2
+
+    def test_file_handler_writes(self, tmp_path: Path) -> None:
+        with patch("gitea_runner_manager.logging_config.Path.home", return_value=tmp_path):
+            logger = get_logger("test_file_writes")
+            logger.info("hello from test")
+
+        log_file = tmp_path / ".local" / "state" / "grm" / "logs" / "grm.log"
+        assert log_file.exists()
+        content = log_file.read_text()
+        assert "hello from test" in content
+        assert "INFO" in content
+
+    def test_respects_grm_log_level(self, monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
+        monkeypatch.setenv("GRM_LOG_LEVEL", "DEBUG")
+        with patch("gitea_runner_manager.logging_config.Path.home", return_value=tmp_path):
+            logger = get_logger("test_env_level")
+            console = [h for h in logger.handlers if type(h) is logging.StreamHandler]
+
+        assert len(console) == 1
+        assert console[0].level == logging.DEBUG
+
+    def test_grm_log_level_warning(self, monkeypatch: pytest.MonkeyPatch, tmp_path: Path) -> None:
+        monkeypatch.setenv("GRM_LOG_LEVEL", "WARNING")
+        with patch("gitea_runner_manager.logging_config.Path.home", return_value=tmp_path):
+            logger = get_logger("test_env_warning")
+            console = [h for h in logger.handlers if type(h) is logging.StreamHandler]
+
+        assert len(console) == 1
+        assert console[0].level == logging.WARNING

tests/unit/test_report.py

@@ -2,6 +2,8 @@
 
 from __future__ import annotations
 
+from unittest.mock import MagicMock, patch
+
 import pytest
 
 from gitea_runner_manager.exceptions import AnsibleError
@@ -43,60 +45,69 @@ class TestStepTracker:
 
 
 class TestTrackSteps:
-    def test_success(self, capsys: pytest.CaptureFixture[str]) -> None:
-        with track_steps() as tracker:
-            tracker.begin("step1")
-            tracker.done()
-            tracker.begin("step2")
-            tracker.done()
-
-        captured = capsys.readouterr()
-        assert "Operation Report" in captured.out
-        assert "step1" in captured.out
-        assert "step2" in captured.out
-        assert "✓" in captured.out
-        assert "completed" in captured.out
-
-    def test_failure_marks_step(self, capsys: pytest.CaptureFixture[str]) -> None:
-        with pytest.raises(AnsibleError, match="fail"):
+    def test_success(self) -> None:
+        mock_logger = MagicMock()
+        with patch("gitea_runner_manager.report.get_logger", return_value=mock_logger):
             with track_steps() as tracker:
                 tracker.begin("step1")
                 tracker.done()
                 tracker.begin("step2")
-                raise AnsibleError("fail")
+                tracker.done()
 
-        captured = capsys.readouterr()
-        assert "Operation Report" in captured.out
-        assert "step1" in captured.out
-        assert "step2" in captured.out
-        assert "✓" in captured.out
-        assert "✗" in captured.out
-        assert "completed" in captured.out
-        assert "failed" in captured.out
+        messages = [call.args[0] for call in mock_logger.info.call_args_list]
+        assert any("Operation Report" in msg for msg in messages)
+        assert any("step1" in msg for msg in messages)
+        assert any("step2" in msg for msg in messages)
+        assert any("✓" in msg for msg in messages)
+        assert any("completed" in msg for msg in messages)
 
-    def test_pending_shown_on_failure(self, capsys: pytest.CaptureFixture[str]) -> None:
+    def test_failure_marks_step(self) -> None:
+        mock_logger = MagicMock()
         with pytest.raises(AnsibleError, match="fail"):
+            with patch("gitea_runner_manager.report.get_logger", return_value=mock_logger):
+                with track_steps() as tracker:
+                    tracker.begin("step1")
+                    tracker.done()
+                    tracker.begin("step2")
+                    raise AnsibleError("fail")
+
+        messages = [call.args[0] for call in mock_logger.info.call_args_list]
+        assert any("step1" in msg for msg in messages)
+        assert any("step2" in msg for msg in messages)
+        assert any("✓" in msg for msg in messages)
+        assert any("✗" in msg for msg in messages)
+        assert any("completed" in msg for msg in messages)
+        assert any("failed" in msg for msg in messages)
+
+    def test_pending_shown_on_failure(self) -> None:
+        mock_logger = MagicMock()
+        with pytest.raises(AnsibleError, match="fail"):
+            with patch("gitea_runner_manager.report.get_logger", return_value=mock_logger):
+                with track_steps() as tracker:
+                    tracker.begin("step1")
+                    raise AnsibleError("fail")
+
+        messages = [call.args[0] for call in mock_logger.info.call_args_list]
+        assert any("✗" in msg for msg in messages)
+        assert any("failed" in msg for msg in messages)
+
+    def test_empty_report(self) -> None:
+        mock_logger = MagicMock()
+        with patch("gitea_runner_manager.report.get_logger", return_value=mock_logger):
+            with track_steps():
+                pass
+
+        messages = [call.args[0] for call in mock_logger.info.call_args_list]
+        assert any("Operation Report" in msg for msg in messages)
+
+    def test_translated_report(self, monkeypatch: pytest.MonkeyPatch) -> None:
+        monkeypatch.setenv("GRM_LANG", "bg")
+        mock_logger = MagicMock()
+        with patch("gitea_runner_manager.report.get_logger", return_value=mock_logger):
             with track_steps() as tracker:
                 tracker.begin("step1")
-                raise AnsibleError("fail")
+                tracker.done()
 
-        captured = capsys.readouterr()
-        assert "✗" in captured.out
-        assert "failed" in captured.out
-
-    def test_empty_report(self, capsys: pytest.CaptureFixture[str]) -> None:
-        with track_steps():
-            pass
-
-        captured = capsys.readouterr()
-        assert "Operation Report" in captured.out
-
-    def test_translated_report(self, monkeypatch: pytest.MonkeyPatch, capsys: pytest.CaptureFixture[str]) -> None:
-        monkeypatch.setenv("GRM_LANG", "bg")
-        with track_steps() as tracker:
-            tracker.begin("step1")
-            tracker.done()
-
-        captured = capsys.readouterr()
-        assert "Отчет за операцията" in captured.out
-        assert "завършено" in captured.out
+        messages = [call.args[0] for call in mock_logger.info.call_args_list]
+        assert any("Отчет за операцията" in msg for msg in messages)
+        assert any("завършено" in msg for msg in messages)