set up print and logging for sage_bootstrap

src/sage_bootstrap/.gitignore

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+/.tox
+/MANIFEST

src/sage_bootstrap/sage-bootstrap

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+#!/usr/bin/env python
+
+import sage_bootstrap
+
+print('done')
+
+from sage_bootstrap.config import Configuration
+
+print(Configuration())

src/sage_bootstrap/sage_bootstrap/__init__.py

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+
+from sage_bootstrap.config import Configuration
+config = Configuration()
+
+from sage_bootstrap.stdio import init_streams
+init_streams(config)
+
+from sage_bootstrap.logger import init_logger
+init_logger(config)

src/sage_bootstrap/sage_bootstrap/config.py

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+# -*- coding: utf-8 -*-
+"""
+Set Up Logging
+
+Logging can be customized using the ``SAGE_BOOTSTRAP`` environment
+variable. It is a comma-separated list of ``key:value`` pairs. They
+are not case sensitive. Valid pairs are:
+
+* ``log:[level]``, where ``[level]`` is one of 
+
+    * ``debug``
+    * ``info``
+    * ``warning``
+    * ``critical``
+    * ``error``
+
+* ``interactive:true`` or ``interactive:false``, to override isatty detection.
+"""
+
+
+#*****************************************************************************
+#       Copyright (C) 2015 Volker Braun <vbraun.name@gmail.com>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#                  http://www.gnu.org/licenses/
+#*****************************************************************************
+
+
+import sys
+import os
+import logging
+
+
+LOG_LEVELS = (
+    'debug',
+    'info',
+    'warning',
+    'critical',
+    'error'
+)
+
+
+
+
+class Configuration(object):
+
+    _initialized = False
+
+    log = 'info'
+
+    interactive = os.isatty(sys.stdout.fileno())
+
+    def __init__(self):
+        if not Configuration._initialized:
+            Configuration._init_from_environ()
+        if self.log not in LOG_LEVELS:
+            raise ValueError('invalid log level: {0}'.format(self.log))
+        assert isinstance(self.interactive, bool)
+
+    @classmethod
+    def _init_from_environ(cls):
+        env = os.environ.get('SAGE_BOOTSTRAP', '').lower()
+        for pair in env.split(','):
+            if not pair.strip():
+                continue
+            key, value = pair.split(':', 1)
+            key = key.strip()
+            value = value.strip()
+            if key == 'log':
+                cls.log = value
+            elif key == 'interactive':
+                if value == 'true':
+                    cls.interactive = True
+                elif value == 'false':
+                    cls.interactive = False
+                else:
+                    raise ValueError('interactive value must be "true" or "false", got "{0}"'
+                                     .format(value))
+            else:
+                raise ValueError('unknown key: "{0}"'.format(key))
+        cls._initialized = True
+
+    def __repr__(self):
+        return '\n'.join([
+            'Configuration:',
+            '  * log = {0}'.format(self.log),
+            '  * interactive = {0}'.format(self.interactive)
+        ])

src/sage_bootstrap/sage_bootstrap/logger.py

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+# -*- coding: utf-8 -*-
+"""
+Set Up Logging
+
+When using a script interactively, logging should go to stdout and be
+human-readable. When using a script as part of a pipe (usually
+involving tee), logging should go to stderr.
+"""
+
+
+#*****************************************************************************
+#       Copyright (C) 2015 Volker Braun <vbraun.name@gmail.com>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#                  http://www.gnu.org/licenses/
+#*****************************************************************************
+
+import sys
+import os
+import logging
+
+logger = logging.getLogger()
+
+
+default_formatter = logging.Formatter(
+    '%(levelname)s [%(module)s.%(funcName)s:%(lineno)s]: %(message)s')
+
+plain_formatter = logging.Formatter('%(message)s')
+
+
+class ExcludeInfoFilter(logging.Filter):
+
+    def filter(self, record):
+        return record.levelno != logging.INFO
+
+class OnlyInfoFilter(logging.Filter):
+
+    def filter(self, record):
+        return record.levelno == logging.INFO
+
+
+def init_logger(config):
+    level = getattr(logging, config.log.upper())
+    logger.setLevel(level)
+    ch_stderr = logging.StreamHandler(sys.stderr)
+    ch_stderr.setLevel(logging.DEBUG)
+    ch_stderr.setFormatter(default_formatter)
+    if config.interactive:
+        ch_stderr.addFilter(ExcludeInfoFilter())
+        ch_stdout = logging.StreamHandler(sys.stdout)
+        ch_stdout.setLevel(logging.DEBUG)
+        ch_stdout.setFormatter(plain_formatter)
+        ch_stdout.addFilter(OnlyInfoFilter())
+        logger.addHandler(ch_stdout)
+    logger.addHandler(ch_stderr)
+

src/sage_bootstrap/sage_bootstrap/stdio.py

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+# -*- coding: utf-8 -*-
+"""
+Set Up Input/output
+
+Output should always be unbuffered so that it appears immediately on
+the terminal.
+"""
+
+#*****************************************************************************
+#       Copyright (C) 2015 Volker Braun <vbraun.name@gmail.com>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#                  http://www.gnu.org/licenses/
+#*****************************************************************************
+
+
+import sys
+import os    
+
+
+class UnbufferedStream(object):
+
+   def __init__(self, stream):
+       self.stream = stream
+
+   def write(self, data):
+       self.stream.write(data)
+       self.stream.flush()
+
+   def __getattr__(self, attr):
+       return getattr(self.stream, attr)
+
+
+REAL_STDOUT = sys.stdout
+REAL_STDERR = sys.stderr
+
+
+def init_streams(config):
+   if not config.interactive:
+      sys.stdout = UnbufferedStream(REAL_STDOUT)

src/sage_bootstrap/setup.py

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+#!/usr/bin/env python
+
+from distutils.core import setup
+
+setup(
+    name='sage_bootstrap',
+    description='',
+    author='Volker Braun',
+    author_email='vbraun.name@gmail.com',
+    packages=['sage_bootstrap'],
+    scripts=['sage-bootstrap'],
+    version='1.0',
+    url='https://www.sagemath.org',
+)

src/sage_bootstrap/test/runnable.py

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+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+"""
+Utility to test running with different values for ``SAGE_BOOTSTRAP``
+"""
+
+#*****************************************************************************
+#       Copyright (C) 2015 Volker Braun <vbraun.name@gmail.com>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#                  http://www.gnu.org/licenses/
+#*****************************************************************************
+
+
+# This function's line numbers are in unit tests, try to not move it
+# up or down. This is why it is up here at the beginning.
+def print_log():
+    import logging
+    log = logging.getLogger()
+    log.debug('This is the debug log level')
+    log.info('This is the info log level')
+    log.warning('This is the warning log level')
+    log.critical('This is the critical log level')
+    log.error('This is the error log level')
+    print('This is printed')
+
+# From here on the line number does not matter
+
+import sys
+import os
+import json
+import subprocess
+
+
+def run_with(command, SAGE_BOOTSTRAP):
+    env = dict(os.environ)
+    env['SAGE_BOOTSTRAP'] = SAGE_BOOTSTRAP
+    proc = subprocess.Popen(
+        [sys.executable, __file__, command],
+        env=env,
+        stdout=subprocess.PIPE, stderr=subprocess.PIPE,
+    )
+    out, err = proc.communicate()
+    return out.decode('ascii'), err.decode('ascii')
+
+
+def run_config_with(SAGE_BOOTSTRAP):
+    out, err = run_with('print_config', SAGE_BOOTSTRAP)
+    assert not err, err
+    return json.loads(out)
+
+
+def print_config():
+    from sage_bootstrap.config import Configuration
+    from sage_bootstrap.stdio import REAL_STDOUT, REAL_STDERR
+    config = Configuration()
+    result = dict(
+        log=config.log,
+        interactive=config.interactive,
+        stdout='default stdout' if sys.stdout == REAL_STDOUT else str(type(sys.stdout)),
+        stderr='default stderr' if sys.stderr == REAL_STDERR else str(type(sys.stderr)),
+    )
+    print(json.dumps(result))
+
+
+def run_log_with(SAGE_BOOTSTRAP):
+    return run_with('print_log', SAGE_BOOTSTRAP)
+
+
+commands = dict(
+    print_config=print_config,
+    print_log=print_log,
+)
+
+
+if __name__ == '__main__':
+    sys.path.insert(0,
+        os.path.abspath(os.path.join(os.path.dirname(__file__), '..')))
+    import sage_bootstrap
+    commands[sys.argv[1]]()

src/sage_bootstrap/test/test_config.py

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+# -*- coding: utf-8 -*-
+
+#*****************************************************************************
+#       Copyright (C) 2015 Volker Braun <vbraun.name@gmail.com>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#                  http://www.gnu.org/licenses/
+#*****************************************************************************
+
+
+import unittest
+from sage_bootstrap.config import Configuration, LOG_LEVELS
+from .runnable import run_config_with
+
+
+class ConfigurationTestCase(unittest.TestCase):
+
+    def test_default(self):
+        """
+        Test the default configuration
+        """
+        config = Configuration()
+        self.assertEqual(config.log, 'info')
+        self.assertTrue(config.interactive)
+
+    def test_example(self):
+        """
+        Test all ``SAGE_BOOTSTRAP`` settings
+        """
+        SAGE_BOOTSTRAP=' loG:CrItIcAl, interactive:TRUE'
+        result = run_config_with(SAGE_BOOTSTRAP)
+        self.assertEqual(len(result), 4)
+        self.assertEqual(result['log'], u'critical')
+        self.assertTrue(result['interactive'])
+        self.assertEqual(result['stdout'], 'default stdout')
+        self.assertEqual(result['stderr'], 'default stderr')
+
+
+    def test_logging(self):
+        """
+        Test that the different log levels are understood
+        """
+        for level in LOG_LEVELS:
+            self.assertEqual(
+                run_config_with('LOG:{0}'.format(level.upper()))['log'],
+                level)
+
+    def test_logging(self):
+        """
+        Test that overriding the isatty detection works
+        """
+        interactive = run_config_with('interactive:true')
+        self.assertTrue(interactive['interactive'])
+        self.assertEqual(interactive['stdout'], 'default stdout')
+        self.assertEqual(interactive['stderr'], 'default stderr')
+        in_pipe = run_config_with('interactive:false')
+        self.assertFalse(in_pipe['interactive'])
+        self.assertEqual(in_pipe['stdout'], u"<class 'sage_bootstrap.stdio.UnbufferedStream'>")
+        self.assertEqual(in_pipe['stderr'], 'default stderr')
+
+