Merge e947e0f into f959040

CHANGELOG.md

@@ -9,6 +9,9 @@ We follow [Semantic Versions](https://semver.org/).
 - Implement `--debug` CLI option (sets the logging level to `DEBUG`)
 - Add class `Config` that provides configuration for the Slow Start Rewatch
 - Add a substitution of placeholders to the `Config` class
+- Add class `App` - the main application class
+- Add class `SlowStartRewatchException` - the base class for exceptions
+- Set up exception handling
 
 
 ## Version 0.1.0

slow_start_rewatch/__main__.py

@@ -2,11 +2,15 @@
 
 import logging
 import sys
+import traceback
 from logging.config import dictConfig
 
 import click
 import structlog
 
+from slow_start_rewatch.app import App
+from slow_start_rewatch.config import Config
+from slow_start_rewatch.exceptions import SlowStartRewatchException
 from slow_start_rewatch.version import distribution_name, version
 
 # Set up logging:
@@ -58,6 +62,7 @@
     wrapper_class=structlog.stdlib.BoundLogger,
     cache_logger_on_first_use=True,
 )
+log = structlog.get_logger()
 
 
 @click.command()
@@ -68,7 +73,27 @@ def main(debug) -> None:
     if debug:
         logging.getLogger().setLevel(logging.DEBUG)
 
-    sys.exit(0)
+    config = Config()
+
+    app = App(config)
+
+    try:
+        app.run()
+    except SlowStartRewatchException as exception:
+        click.echo(click.style(str(exception), fg="red"), err=True)
+
+        if exception.hint:
+            click.echo(exception.hint)
+
+        sys.exit(exception.exit_code)
+    except Exception:
+        log.exception("unhandled_exception")
+        click.echo(
+            click.style("An unexpected error has occurred:\n", fg="red") +
+            traceback.format_exc(),
+            err=True,
+        )
+        sys.exit(1)
 
 
 if __name__ == "__main__":

slow_start_rewatch/app.py

@@ -0,0 +1,17 @@
+# -*- coding: utf-8 -*-
+
+import click
+
+from slow_start_rewatch.config import Config
+
+
+class App(object):
+    """The main application object."""
+
+    def __init__(self, config: Config) -> None:
+        """Initialize App."""
+        self.config = config
+
+    def run(self) -> None:
+        """Runs the application."""
+        click.echo("Starting the Slow Start Rewatch...")

slow_start_rewatch/exceptions.py

@@ -0,0 +1,18 @@
+# -*- coding: utf-8 -*-
+
+from typing import Optional
+
+
+class SlowStartRewatchException(Exception):
+    """An exception that slow_start_rewatch can handle."""
+
+    def __init__(self, message: str, hint: Optional[str] = None, exit_code=1):
+        """Initialize SlowStartRewatchException."""
+        super().__init__(message)
+        self.message = message
+        self.hint = hint
+        self.exit_code = exit_code
+
+    def __str__(self):
+        """Return string representation of the exception."""
+        return self.message

tests/conftest.py

@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+
+"""
+This module is used to provide configuration, fixtures, and plugins for pytest.
+
+It may be also used for extending doctest's context:
+1. https://docs.python.org/3/library/doctest.html
+2. https://docs.pytest.org/en/latest/doctest.html
+"""
+
+from dotty_dict import dotty
+
+from slow_start_rewatch.config import Config
+
+
+class MockConfig(Config):
+    """Simplified version of the Config class."""
+
+    def __init__(self, config_data=None) -> None:
+        """Initialize MockConfig."""
+        self.config = dotty(config_data)

tests/test_app.py

@@ -0,0 +1,13 @@
+# -*- coding: utf-8 -*-
+
+from slow_start_rewatch.app import App
+from tests.conftest import MockConfig
+
+
+def test_run_successfully(capsys):
+    """Test that the App runs."""
+    app = App(MockConfig())
+    app.run()
+    captured = capsys.readouterr()
+
+    assert "Slow Start" in captured.out

tests/test_main.py

@@ -1,31 +1,39 @@
 # -*- coding: utf-8 -*-
 
 import logging
+from unittest.mock import patch
 
 from click.testing import CliRunner
 
 from slow_start_rewatch.__main__ import main
+from slow_start_rewatch.app import App
+from slow_start_rewatch.exceptions import SlowStartRewatchException
 
 
-def test_run_successfully():
+@patch.object(App, "run")
+def test_run_successfully(mock_run):
     """Test launching the program without params."""
     runner = CliRunner()
 
     cli_result = runner.invoke(main)
+    assert mock_run.call_count == 1
     assert cli_result.exit_code == 0
     assert logging.getLogger().getEffectiveLevel() == logging.CRITICAL
 
 
-def test_check_version():
+@patch.object(App, "run")
+def test_check_version(mock_run):
     """Test the launch with the ``--version`` option."""
     runner = CliRunner()
 
     cli_result = runner.invoke(main, ["--version"])
     assert cli_result.exit_code == 0
     assert "slow-start-rewatch, version" in cli_result.output
+    assert mock_run.call_count == 0
 
 
-def test_debug(request):
+@patch.object(App, "run")
+def test_debug(mock_run, request):
     """
     Test the launch with the ``--debug`` option.
 
@@ -44,3 +52,43 @@ def test_debug(request):
 
     assert logger.getEffectiveLevel() == logging.DEBUG
     assert cli_result.exit_code == 0
+
+
+@patch.object(App, "run")
+def test_handled_exception_with_hint(mock_run):
+    """Test the output of a handled exception (with a hint)."""
+    runner = CliRunner()
+    mock_run.side_effect = SlowStartRewatchException(
+        message="The cute app is pouting.",
+        hint="Give her headpats.",
+    )
+
+    cli_result = runner.invoke(main)
+    assert cli_result.exit_code == 1
+    assert "pouting" in cli_result.output
+    assert "headpats" in cli_result.output
+
+
+@patch.object(App, "run")
+def test_handled_exception_without_hint(mock_run):
+    """Test the output of an exception without a hint."""
+    runner = CliRunner()
+    mock_run.side_effect = SlowStartRewatchException(
+        message="The cute app is unreachable.",
+    )
+
+    cli_result = runner.invoke(main)
+    assert cli_result.exit_code == 1
+    assert "unreachable" in cli_result.output
+
+
+@patch.object(App, "run")
+def test_unhandled_exception(mock_run):
+    """Test the output of an unhandled exception."""
+    runner = CliRunner()
+    mock_run.side_effect = Exception("Reddit API is pouting.")
+
+    cli_result = runner.invoke(main)
+    assert cli_result.exit_code == 1
+    assert "unexpected error" in cli_result.output
+    assert "pouting" in cli_result.output