Merge pull request #15 from dwhswenson/logging

Add --log (logging conf) option to main command

Author: dwhswenson

paths_cli/cli.py

@@ -4,6 +4,8 @@
 """
 # builds off the example of MultiCommand in click's docs
 import collections
+import logging
+import logging.config
 import os
 
 import click
@@ -36,16 +38,30 @@ def __init__(self, *args, **kwargs):
                 self.plugin_folders.append(folder)
 
         plugin_files = self._list_plugin_files(self.plugin_folders)
-        self.plugins = self._load_plugin_files(plugin_files)
+        plugins = self._load_plugin_files(plugin_files)
 
         self._get_command = {}
         self._sections = collections.defaultdict(list)
-        for plugin in self.plugins:
-            self._get_command[plugin.name] = plugin.func
-            self._sections[plugin.section].append(plugin.name)
+        self.plugins = []
+        for plugin in plugins:
+            self._register_plugin(plugin)
 
         super(OpenPathSamplingCLI, self).__init__(*args, **kwargs)
 
+    def _register_plugin(self, plugin):
+        self.plugins.append(plugin)
+        self._get_command[plugin.name] = plugin.func
+        self._sections[plugin.section].append(plugin.name)
+
+    def _deregister_plugin(self, plugin):
+        # mainly used in testing
+        self.plugins.remove(plugin)
+        del self._get_command[plugin.name]
+        self._sections[plugin.section].remove(plugin.name)
+
+    def plugin_for_command(self, command_name):
+        return {p.name: p for p in self.plugins}[name]
+
     @staticmethod
     def _list_plugin_files(plugin_folders):
         def is_plugin(filename):
@@ -118,16 +134,17 @@ def format_commands(self, ctx, formatter):
     openpathsampling strip-snapshots --help
 """
 
-OPS_CLI = OpenPathSamplingCLI(
-    name="openpathsampling",
-    help=_MAIN_HELP,
-    context_settings=CONTEXT_SETTINGS
-)
-
-def main():  # no-cov
-    OPS_CLI()
+@click.command(cls=OpenPathSamplingCLI, name="openpathsampling",
+               help=_MAIN_HELP, context_settings=CONTEXT_SETTINGS)
+@click.option('--log', type=click.Path(exists=True, readable=True),
+              help="logging configuration file")
+def main(log):
+    if log:
+        logging.config.fileConfig(log, disable_existing_loggers=False)
+    # TODO: if log not given, check for logging.conf in .openpathsampling/
 
+    logger = logging.getLogger(__name__)
+    logger.debug("About to run command")  # TODO: maybe log invocation?
 
 if __name__ == '__main__':  # no-cov
-    main()
-    # print("list commands:", cli.list_commands())
+    cli()

paths_cli/tests/null_command.py

@@ -0,0 +1,24 @@
+import logging
+import click
+@click.command(
+    'null-command',
+    short_help="Do nothing (testing)"
+)
+def null_command():
+    logger = logging.getLogger(__name__)
+    logger.info("Running null command")
+
+CLI = null_command
+SECTION = "Workflow"
+
+class NullCommandContext(object):
+    """Context that registers/deregisters the null command (for tests)"""
+    def __init__(self, cli):
+        self.plugin = cli._load_plugin_files([__file__])[0]
+        self.cli = cli
+
+    def __enter__(self):
+        self.cli._register_plugin(self.plugin)
+
+    def __exit__(self, type, value, traceback):
+        self.cli._deregister_plugin(self.plugin)

paths_cli/tests/test_cli.py

@@ -0,0 +1,58 @@
+import pytest
+from click.testing import CliRunner
+
+import logging
+
+from paths_cli.cli import *
+from .null_command import NullCommandContext
+
+class TestOpenPathSamplingCLI(object):
+    def setup(self):
+        # TODO: patch out the directory to fake the plugins
+        self.cli = OpenPathSamplingCLI()
+
+    def test_plugins(self):
+        pytest.skip()
+        pass
+
+    def test_get_command(self):
+        # test renamings
+        pytest.skip()
+        pass
+
+    def test_format_commands(self):
+        pytest.skip()
+        # use a mock to get the formatter
+        # test that it skips a section if it is empty
+        pass
+
+@pytest.mark.parametrize('with_log', [True, False])
+def test_main_log(with_log):
+    logged_stdout = "About to run command\n"
+    cmd_stdout = "Running null command\n"
+    logfile_text = "\n".join([
+        "[loggers]", "keys=root", "",
+        "[handlers]", "keys=std", "",
+        "[formatters]", "keys=default", "",
+        "[formatter_default]", "format=%(message)s", "",
+        "[handler_std]", "class=StreamHandler", "level=NOTSET",
+        "formatter=default", "args=(sys.stdout,)", ""
+        "[logger_root]", "level=DEBUG", "handlers=std"
+    ])
+    runner = CliRunner()
+    invocation = {
+        True: ['--log', 'logging.conf', 'null-command'],
+        False: ['null-command']
+    }[with_log]
+    expected = {
+        True: logged_stdout + cmd_stdout,
+        False: ""
+    }[with_log]
+    with runner.isolated_filesystem():
+        with open("logging.conf", mode='w') as log_conf:
+            log_conf.write(logfile_text)
+
+        with NullCommandContext(main):
+            result = runner.invoke(main, invocation)
+    found = result.stdout_bytes
+    assert found.decode('utf-8') == expected