Reasonable defaults, isolate tests, EOS_LOGGING_LEVEL, EOS_CONFIG_DIR

* Add EOS_CONFIG_DIR to set config dir (relative path to EOS_DIR or
   absolute path).
    - config_folder_path read-only
    - config_file_path read-only
 * Default values to support app start with empty config:
    - latitude/longitude (Berlin)
    - optimization_ev_available_charge_rates_percent (null, so model
      default value is used)
    - Enable Akkudoktor electricity price forecast (docker-compose).
 * Fix some endpoints (empty data, remove unused params, fix types).
 * cacheutil: Use cache dir. Closes #240
 * Support EOS_LOGGING_LEVEL environment variable to set log level.
 * tests: All tests use separate temporary config
    - Add pytest switch --check-config-side-effect to check user
      config file existence after each test. Will also fail if user config
      existed before test execution (but will only check after the test has
      run).
      Enable flag in github workflow.
    - Globally mock platformdirs in config module. Now no longer required
      to patch individually.
      Function calls to config instance (e.g. merge_settings_from_dict)
      were unaffected previously.
 * Set Berlin as default location (default config/docker-compose).

tests/conftest.py

@@ -1,17 +1,17 @@
 import logging
-import shutil
+import os
 import subprocess
 import sys
 import tempfile
 from pathlib import Path
 from typing import Optional
+from unittest.mock import PropertyMock, patch
 
 import pendulum
-import platformdirs
 import pytest
 from xprocess import ProcessStarter
 
-from akkudoktoreos.config.config import get_config
+from akkudoktoreos.config.config import ConfigEOS, get_config
 from akkudoktoreos.utils.logutil import get_logger
 
 logger = get_logger(__name__)
@@ -42,6 +42,12 @@ def pytest_addoption(parser):
     parser.addoption(
         "--full-run", action="store_true", default=False, help="Run with all optimization tests."
     )
+    parser.addoption(
+        "--check-config-side-effect",
+        action="store_true",
+        default=False,
+        help="Verify that user config file is non-existent (will also fail if user config file exists before test run).",
+    )
 
 
 @pytest.fixture
@@ -49,97 +55,107 @@ def is_full_run(request):
     yield bool(request.config.getoption("--full-run"))
 
 
+@pytest.fixture(autouse=True)
+def config_mixin(config_eos):
+    with patch(
+        "akkudoktoreos.core.coreabc.ConfigMixin.config", new_callable=PropertyMock
+    ) as config_mixin_patch:
+        config_mixin_patch.return_value = config_eos
+        yield config_mixin_patch
+
+
+# Test if test has side effect of writing to system (user) config file
+# Before activating, make sure that no user config file exists (e.g. ~/.config/net.akkudoktoreos.eos/EOS.config.json)
+@pytest.fixture(autouse=True)
+def cfg_non_existent(request):
+    yield
+    if bool(request.config.getoption("--check-config-side-effect")):
+        from platformdirs import user_config_dir
+
+        user_dir = user_config_dir(ConfigEOS.APP_NAME)
+        assert not Path(user_dir).joinpath(ConfigEOS.CONFIG_FILE_NAME).exists()
+
+
+@pytest.fixture(autouse=True)
+def user_config_dir(config_default_dirs):
+    with patch(
+        "akkudoktoreos.config.config.user_config_dir",
+        return_value=str(config_default_dirs[0]),
+    ) as user_dir_patch:
+        yield user_dir_patch
+
+
+@pytest.fixture(autouse=True)
+def user_data_dir(config_default_dirs):
+    with patch(
+        "akkudoktoreos.config.config.user_data_dir",
+        return_value=str(config_default_dirs[-1] / "data"),
+    ) as user_dir_patch:
+        yield user_dir_patch
+
+
 @pytest.fixture
-def reset_config(disable_debug_logging):
+def config_eos(
+    disable_debug_logging,
+    user_config_dir,
+    user_data_dir,
+    config_default_dirs,
+    monkeypatch,
+) -> ConfigEOS:
     """Fixture to reset EOS config to default values."""
+    monkeypatch.setenv("data_cache_subpath", str(config_default_dirs[-1] / "data/cache"))
+    monkeypatch.setenv("data_output_subpath", str(config_default_dirs[-1] / "data/output"))
+    config_file = config_default_dirs[0] / ConfigEOS.CONFIG_FILE_NAME
+    assert not config_file.exists()
     config_eos = get_config()
     config_eos.reset_settings()
-    config_eos.reset_to_defaults()
+    assert config_file == config_eos.config_file_path
+    assert config_file.exists()
+    assert config_default_dirs[-1] / "data" == config_eos.data_folder_path
+    assert config_default_dirs[-1] / "data/cache" == config_eos.data_cache_path
+    assert config_default_dirs[-1] / "data/output" == config_eos.data_output_path
     return config_eos
 
 
 @pytest.fixture
 def config_default_dirs():
     """Fixture that provides a list of directories to be used as config dir."""
-    config_eos = get_config()
-    # Default config directory from platform user config directory
-    config_default_dir_user = Path(platformdirs.user_config_dir(config_eos.APP_NAME))
-    # Default config directory from current working directory
-    config_default_dir_cwd = Path.cwd()
-    # Default config directory from default config file
-    config_default_dir_default = Path(__file__).parent.parent.joinpath("src/akkudoktoreos/data")
-    return config_default_dir_user, config_default_dir_cwd, config_default_dir_default
+    with tempfile.TemporaryDirectory() as tmp_user_home_dir:
+        # Default config directory from platform user config directory
+        config_default_dir_user = Path(tmp_user_home_dir) / "config"
+        # Default config directory from current working directory
+        config_default_dir_cwd = Path.cwd()
+        # Default config directory from default config file
+        config_default_dir_default = Path(__file__).parent.parent.joinpath("src/akkudoktoreos/data")
+
+        # Default data directory from platform user data directory
+        data_default_dir_user = Path(tmp_user_home_dir)
+        yield (
+            config_default_dir_user,
+            config_default_dir_cwd,
+            config_default_dir_default,
+            data_default_dir_user,
+        )
 
 
 @pytest.fixture
-def stash_config_file(config_default_dirs):
-    """Fixture to temporarily stash away an existing config file during a test.
-
-    If the specified config file exists, it moves the file to a temporary directory.
-    The file is restored to its original location after the test.
-
-    Keep right most in fixture parameter list to assure application at last.
-
-    Returns:
-        Path: Path to the stashed config file.
-    """
-    config_eos = get_config()
-    config_default_dir_user, config_default_dir_cwd, _ = config_default_dirs
-
-    config_file_path_user = config_default_dir_user.joinpath(config_eos.CONFIG_FILE_NAME)
-    config_file_path_cwd = config_default_dir_cwd.joinpath(config_eos.CONFIG_FILE_NAME)
-
-    original_config_file_user = None
-    original_config_file_cwd = None
-    if config_file_path_user.exists():
-        original_config_file_user = config_file_path_user
-    if config_file_path_cwd.exists():
-        original_config_file_cwd = config_file_path_cwd
-
-    temp_dir = tempfile.TemporaryDirectory()
-    temp_file_user = None
-    temp_file_cwd = None
-
-    # If the file exists, move it to the temporary directory
-    if original_config_file_user:
-        temp_file_user = Path(temp_dir.name) / f"user.{original_config_file_user.name}"
-        shutil.move(original_config_file_user, temp_file_user)
-        assert not original_config_file_user.exists()
-        logger.debug(f"Stashed: '{original_config_file_user}'")
-    if original_config_file_cwd:
-        temp_file_cwd = Path(temp_dir.name) / f"cwd.{original_config_file_cwd.name}"
-        shutil.move(original_config_file_cwd, temp_file_cwd)
-        assert not original_config_file_cwd.exists()
-        logger.debug(f"Stashed: '{original_config_file_cwd}'")
-
-    # Yield the temporary file path to the test
-    yield temp_file_user, temp_file_cwd
-
-    # Cleanup after the test
-    if temp_file_user:
-        # Restore the file to its original location
-        shutil.move(temp_file_user, original_config_file_user)
-        assert original_config_file_user.exists()
-    if temp_file_cwd:
-        # Restore the file to its original location
-        shutil.move(temp_file_cwd, original_config_file_cwd)
-        assert original_config_file_cwd.exists()
-    temp_dir.cleanup()
-
-
-@pytest.fixture
-def server(xprocess, tmp_path: Path):
+def server(xprocess, config_eos, config_default_dirs):
     """Fixture to start the server.
 
     Provides URL of the server.
     """
 
     class Starter(ProcessStarter):
+        # Set environment before any subprocess run, to keep custom config dir
+        env = os.environ.copy()
+        env["EOS_DIR"] = str(config_default_dirs[-1])
+
         # assure server to be installed
         try:
             subprocess.run(
                 [sys.executable, "-c", "import akkudoktoreos.server.fastapi_server"],
                 check=True,
+                env=env,
                 stdout=subprocess.PIPE,
                 stderr=subprocess.PIPE,
             )
@@ -154,11 +170,6 @@ def server(xprocess, tmp_path: Path):
 
         # command to start server process
         args = [sys.executable, "-m", "akkudoktoreos.server.fastapi_server"]
-        config_eos = get_config()
-        settings = {
-            "data_folder_path": tmp_path,
-        }
-        config_eos.merge_settings_from_dict(settings)
 
         # startup pattern
         pattern = "Application startup complete."
@@ -174,6 +185,7 @@ def server(xprocess, tmp_path: Path):
 
     # ensure process is running and return its logfile
     pid, logfile = xprocess.ensure("eos", Starter)
+    print(f"View xprocess logfile at: {logfile}")
 
     # create url/port info to the server
     url = "http://127.0.0.1:8503"