Merge pull request #453 from bradmw/notify

Reporter (tells user about important stuff)

letsencrypt/cli.py

@@ -1,5 +1,6 @@
 """Let's Encrypt CLI."""
 # TODO: Sanity check all input.  Be sure to avoid shell code etc...
+import atexit
 import argparse
 import logging
 import os
@@ -20,6 +21,7 @@ from letsencrypt import errors
 from letsencrypt import interfaces
 from letsencrypt import le_util
 from letsencrypt import log
+from letsencrypt import reporter
 
 from letsencrypt.display import util as display_util
 from letsencrypt.display import ops as display_ops
@@ -359,6 +361,11 @@ def main(args=sys.argv[1:]):
         displayer = display_util.NcursesDisplay()
     zope.component.provideUtility(displayer)
 
+    # Reporter
+    report = reporter.Reporter()
+    zope.component.provideUtility(report)
+    atexit.register(report.print_messages)
+
     # Logging
     level = -args.verbose_count * 10
     logger = logging.getLogger()

letsencrypt/interfaces.py

@@ -351,3 +351,30 @@ class IValidator(zope.interface.Interface):
 
     def hsts(name):
         """Verify HSTS header is enabled."""
+
+
+class IReporter(zope.interface.Interface):
+    """Interface to collect and display information to the user."""
+
+    HIGH_PRIORITY = zope.interface.Attribute(
+        "Used to denote high priority messages")
+    MEDIUM_PRIORITY = zope.interface.Attribute(
+        "Used to denote medium priority messages")
+    LOW_PRIORITY = zope.interface.Attribute(
+        "Used to denote low priority messages")
+
+    def add_message(self, msg, priority, on_crash=False):
+        """Adds msg to the list of messages to be printed.
+
+        :param str msg: Message to be displayed to the user.
+
+        :param int priority: One of HIGH_PRIORITY, MEDIUM_PRIORITY, or
+            LOW_PRIORITY.
+
+        :param bool on_crash: Whether or not the message should be printed if
+            the program exits abnormally.
+
+        """
+
+    def print_messages(self):
+        """Prints messages to the user and clears the message queue."""

letsencrypt/reporter.py

@@ -0,0 +1,68 @@
+"""Collects and displays information to the user."""
+import collections
+import Queue
+import sys
+import textwrap
+
+import zope.interface
+
+from letsencrypt import interfaces
+
+
+class Reporter(object):
+    """Collects and displays information to the user.
+
+    :ivar `Queue.PriorityQueue` messages: Messages to be displayed to the user.
+
+    """
+
+    zope.interface.implements(interfaces.IReporter)
+
+    HIGH_PRIORITY, MEDIUM_PRIORITY, LOW_PRIORITY = xrange(3)
+    _RESET = '\033[0m'
+    _BOLD = '\033[1m'
+    _msg_type = collections.namedtuple('Msg', 'priority, text, on_crash')
+
+    def __init__(self):
+        self.messages = Queue.PriorityQueue()
+
+    def add_message(self, msg, priority, on_crash=False):
+        """Adds msg to the list of messages to be printed.
+
+        :param str msg: Message to be displayed to the user.
+
+        :param int priority: One of HIGH_PRIORITY, MEDIUM_PRIORITY, or
+            LOW_PRIORITY.
+
+        :param bool on_crash: Whether or not the message should be printed if
+            the program exits abnormally.
+
+        """
+        assert priority >= self.HIGH_PRIORITY and priority <= self.LOW_PRIORITY
+        self.messages.put(self._msg_type(priority, msg, on_crash))
+
+    def print_messages(self):
+        """Prints messages to the user and clears the message queue.
+
+        If there is an unhandled exception, only messages for which on_crash is
+        True are printed.
+
+        """
+        bold_on = False
+        if not self.messages.empty():
+            no_exception = sys.exc_info()[0] is None
+            bold_on = sys.stdout.isatty()
+            if bold_on:
+                sys.stdout.write(self._BOLD)
+            print 'IMPORTANT NOTES:'
+            wrapper = textwrap.TextWrapper(initial_indent=' - ',
+                                           subsequent_indent=' '*3)
+        while not self.messages.empty():
+            msg = self.messages.get()
+            if no_exception or msg.on_crash:
+                if bold_on and msg.priority > self.HIGH_PRIORITY:
+                    sys.stdout.write(self._RESET)
+                    bold_on = False
+                print wrapper.fill(msg.text)
+        if bold_on:
+            sys.stdout.write(self._RESET)

letsencrypt/tests/reporter_test.py

@@ -0,0 +1,73 @@
+"""Tests for letsencrypt/reporter.py"""
+import StringIO
+import sys
+import unittest
+
+
+class ReporterTest(unittest.TestCase):
+    def setUp(self):
+        from letsencrypt import reporter
+        self.reporter = reporter.Reporter()
+
+        self.old_stdout = sys.stdout
+        sys.stdout = StringIO.StringIO()
+
+    def tearDown(self):
+        sys.stdout = self.old_stdout
+
+    def test_tty_print_empty(self):
+        sys.stdout.isatty = lambda: True
+        self.test_no_tty_print_empty()
+
+    def test_no_tty_print_empty(self):
+        self.reporter.print_messages()
+        self.assertEqual(sys.stdout.getvalue(), "")
+        try:
+            raise ValueError
+        except ValueError:
+            self.reporter.print_messages()
+        self.assertEqual(sys.stdout.getvalue(), "")
+
+    def test_tty_successful_exit(self):
+        sys.stdout.isatty = lambda: True
+        self._successful_exit_common()
+
+    def test_no_tty_successful_exit(self):
+        self._successful_exit_common()
+
+    def test_tty_unsuccessful_exit(self):
+        sys.stdout.isatty = lambda: True
+        self._unsuccessful_exit_common()
+
+    def test_no_tty_unsuccessful_exit(self):
+        self._unsuccessful_exit_common()
+
+    def _successful_exit_common(self):
+        self._add_messages()
+        self.reporter.print_messages()
+        output = sys.stdout.getvalue()
+        self.assertTrue("IMPORTANT NOTES:" in output)
+        self.assertTrue("High" in output)
+        self.assertTrue("Med" in output)
+        self.assertTrue("Low" in output)
+
+    def _unsuccessful_exit_common(self):
+        self._add_messages()
+        try:
+            raise ValueError
+        except ValueError:
+            self.reporter.print_messages()
+        output = sys.stdout.getvalue()
+        self.assertTrue("IMPORTANT NOTES:" in output)
+        self.assertTrue("High" in output)
+        self.assertTrue("Med" not in output)
+        self.assertTrue("Low" not in output)
+
+    def _add_messages(self):
+        self.reporter.add_message("High", self.reporter.HIGH_PRIORITY, True)
+        self.reporter.add_message("Med", self.reporter.MEDIUM_PRIORITY)
+        self.reporter.add_message("Low", self.reporter.LOW_PRIORITY)
+
+
+if __name__ == "__main__":
+    unittest.main() # pragma: no cover