Continue with quotation cut even if html cut throws an exception

.build/Dockerfile

@@ -1,20 +0,0 @@
-FROM python:3.9-slim-buster AS deps
-
-RUN apt-get update && \
-    apt-get install -y build-essential git curl python3-dev libatlas3-base libatlas-base-dev liblapack-dev libxml2 libxml2-dev libffi6 libffi-dev musl-dev libxslt-dev
-
-FROM deps AS testable
-ARG REPORT_PATH
-
-VOLUME ["/var/mailgun", "/etc/mailgun/ssl", ${REPORT_PATH}]
-
-ADD . /app
-WORKDIR /app
-COPY wheel/* /wheel/
-
-RUN mkdir -p ${REPORT_PATH}
-
-RUN python ./setup.py build bdist_wheel -d /wheel && \
-    pip install --no-deps /wheel/*
-
-ENTRYPOINT ["/bin/sh", "/app/run_tests.sh"]

.gitignore

@@ -54,6 +54,3 @@ _trial_temp
 
 # OSX
 .DS_Store
-
-# vim-backup
-*.bak

requirements.txt

@@ -1,11 +0,0 @@
-chardet>=1.0.1
-# cchardet>=0.3.5
-cssselect
-html5lib
-joblib
-lxml>=2.3.3
-numpy
-regex>=1
-scikit-learn>=1.0.0
-scipy
-six>=1.10.0

run_tests.sh

@@ -1,4 +0,0 @@
-#!/usr/bin/env bash
-set -ex
-REPORT_PATH="${REPORT_PATH:-./}"
-nosetests --with-xunit --with-coverage --cover-xml --cover-xml-file $REPORT_PATH/coverage.xml --xunit-file=$REPORT_PATH/nosetests.xml --cover-package=talon .

setup.py

@@ -5,10 +5,10 @@ from setuptools.command.install import install
 
 class InstallCommand(install):
     user_options = install.user_options + [
-        ("no-ml", None, "Don't install without Machine Learning modules."),
+        ('no-ml', None, "Don't install without Machine Learning modules."),
     ]
 
-    boolean_options = install.boolean_options + ["no-ml"]
+    boolean_options = install.boolean_options + ['no-ml']
 
     def initialize_options(self):
         install.initialize_options(self)
@@ -18,47 +18,46 @@ class InstallCommand(install):
         install.finalize_options(self)
         if self.no_ml:
             dist = self.distribution
-            dist.packages = find_packages(
+            dist.packages=find_packages(exclude=[
-                exclude=[
+                'tests',
-                    "tests",
+                'tests.*',
-                    "tests.*",
+                'talon.signature',
-                    "talon.signature",
+                'talon.signature.*',
-                    "talon.signature.*",
+            ])
-                ]
+            for not_required in ['numpy', 'scipy', 'scikit-learn==0.16.1']:
-            )
-            for not_required in ["numpy", "scipy", "scikit-learn==0.24.1"]:
                 dist.install_requires.remove(not_required)
 
 
-setup(
+setup(name='talon',
-    name="talon-o2w",
+      version='1.4.8',
-    version="1.6.1",
+      description=("Mailgun library "
-    description=(
+                   "to extract message quotations and signatures."),
-        "Mailgun library " "to extract message quotations and signatures."
-    ),
       long_description=open("README.rst").read(),
-    author="Mailgun Inc.",
+      author='Mailgun Inc.',
-    author_email="admin@mailgunhq.com",
+      author_email='admin@mailgunhq.com',
-    url="https://github.com/mailgun/talon",
+      url='https://github.com/mailgun/talon',
-    license="APACHE2",
+      license='APACHE2',
       cmdclass={
-        "install": InstallCommand,
+          'install': InstallCommand,
       },
-    packages=find_packages(exclude=["tests", "tests.*"]),
+      packages=find_packages(exclude=['tests', 'tests.*']),
       include_package_data=True,
       zip_safe=True,
       install_requires=[
-        "lxml",
+          "lxml>=2.3.3",
-        "regex",
+          "regex>=1",
           "numpy",
           "scipy",
-        "scikit-learn>=1.0.0",
+          "scikit-learn==0.16.1", # pickled versions of classifier, else rebuild
-        "chardet",
+          'chardet>=1.0.1',
-        #          "cchardet",
+          'cchardet>=0.3.5',
-        "cssselect",
+          'cssselect',
-        "six",
+          'six>=1.10.0',
-        "html5lib",
+          'html5lib'
-        "joblib",
           ],
-    tests_require=["mock", "nose", "coverage"],
+      tests_require=[
+          "mock",
+          "nose>=1.2.1",
+          "coverage"
+          ]
       )

talon/quotations.py

@@ -6,17 +6,18 @@ original messages (without quoted messages)
 """
 
 from __future__ import absolute_import
-
+import regex as re
 import logging
 from copy import deepcopy
 
-import regex as re
+from lxml import html, etree
-from lxml import etree, html
-from six.moves import range
 
+from talon.utils import (get_delimiter, html_tree_to_text,
+                         html_document_fromstring)
 from talon import html_quotations
-from talon.utils import (get_delimiter, html_document_fromstring,
+from six.moves import range
-                         html_tree_to_text)
+import six
+
 
 log = logging.getLogger(__name__)
 
@@ -93,7 +94,7 @@ RE_ON_DATE_WROTE_SMB = re.compile(
     )
 
 RE_QUOTATION = re.compile(
-    r"""
+    r'''
     (
         # quotation border: splitter line or a number of quotation marker lines
         (?:
@@ -111,10 +112,10 @@ RE_QUOTATION = re.compile(
 
     # after quotations should be text only or nothing at all
     [te]*$
-    """, re.VERBOSE)
+    ''', re.VERBOSE)
 
 RE_EMPTY_QUOTATION = re.compile(
-    r"""
+    r'''
     (
         # quotation border: splitter line or a number of quotation marker lines
         (?:
@@ -124,7 +125,7 @@ RE_EMPTY_QUOTATION = re.compile(
         )
     )
     e*
-    """, re.VERBOSE)
+    ''', re.VERBOSE)
 
 # ------Original Message------ or ---- Reply Message ----
 # With variations in other languages.
@@ -192,6 +193,9 @@ RE_PARENTHESIS_LINK = re.compile("\(https?://")
 
 SPLITTER_MAX_LINES = 6
 MAX_LINES_COUNT = 1000
+# an extensive research shows that exceeding this limit
+# leads to excessive processing time
+MAX_HTML_LEN = 2794202
 
 QUOT_PATTERN = re.compile('^>+ ?')
 NO_QUOT_LINE = re.compile('^[^>].*[\S].*')
@@ -342,6 +346,9 @@ def _replace_link_brackets(msg_body):
 
     Converts msg_body into a unicode
     """
+    if isinstance(msg_body, bytes):
+        msg_body = msg_body.decode('utf8')
+
     def link_wrapper(link):
         newline_index = msg_body[:link.start()].rfind("\n")
         if msg_body[newline_index + 1] == ">":
@@ -381,6 +388,8 @@ def postprocess(msg_body):
 
 def extract_from_plain(msg_body):
     """Extracts a non quoted message from provided plain text."""
+    stripped_text = msg_body
+
     delimiter = get_delimiter(msg_body)
     msg_body = preprocess(msg_body, delimiter)
     # don't process too long messages
@@ -412,27 +421,25 @@ def extract_from_html(msg_body):
 
     Returns a unicode string.
     """
-    if msg_body.strip() == "":
+    if isinstance(msg_body, six.text_type):
-        return msg_body
+        msg_body = msg_body.encode('utf8')
+    elif not isinstance(msg_body, bytes):
+        msg_body = msg_body.encode('ascii')
 
-    msg_body = msg_body.replace("\r\n", "\n")
+    result = _extract_from_html(msg_body)
-    # Cut out xml and doctype tags to avoid conflict with unicode decoding.
+    if isinstance(result, bytes):
-    msg_body = re.sub(r"\<\?xml.+\?\>|\<\!DOCTYPE.+]\>", "", msg_body)
+        result = result.decode('utf8')
-    html_tree = html_document_fromstring(msg_body)
-    if html_tree is None:
-        return msg_body
-
-    result = extract_from_html_tree(html_tree)
-    if not result:
-        return msg_body
 
     return result
 
 
-def extract_from_html_tree(html_tree):
+def _extract_from_html(msg_body):
     """
-    Extract not quoted message from provided parsed html tree using tags and
+    Extract not quoted message from provided html message body
-    plain text algorithm.
+    using tags and plain text algorithm.
+
+    Cut out first some encoding html tags such as xml and doctype
+    for avoiding conflict with unicode decoding
 
     Cut out the 'blockquote', 'gmail_quote' tags.
     Cut Microsoft quotations.
@@ -445,6 +452,20 @@ def extract_from_html_tree(html_tree):
     then checking deleted checkpoints,
     then deleting necessary tags.
     """
+    if msg_body.strip() == b'':
+        return msg_body
+
+    msg_body = msg_body.replace(b'\r\n', b'\n')
+
+    msg_body = re.sub(r"\<\?xml.+\?\>|\<\!DOCTYPE.+]\>", "", msg_body)
+
+    html_tree = html_document_fromstring(msg_body)
+
+    if html_tree is None:
+        return msg_body
+
+    cut_quotations = False
+    try:
         cut_quotations = (html_quotations.cut_gmail_quote(html_tree) or
                           html_quotations.cut_zimbra_quote(html_tree) or
                           html_quotations.cut_blockquote(html_tree) or
@@ -452,6 +473,10 @@ def extract_from_html_tree(html_tree):
                           html_quotations.cut_by_id(html_tree) or
                           html_quotations.cut_from_block(html_tree)
                           )
+    except Exception as e:
+        log.exception('during html quotations cut')
+        pass
+
     html_tree_copy = deepcopy(html_tree)
 
     number_of_checkpoints = html_quotations.add_checkpoint(html_tree, 0)
@@ -462,7 +487,7 @@ def extract_from_html_tree(html_tree):
 
     # Don't process too long messages
     if len(lines) > MAX_LINES_COUNT:
-        return None
+        return msg_body
 
     # Collect checkpoints on each line
     line_checkpoints = [
@@ -481,7 +506,7 @@ def extract_from_html_tree(html_tree):
     lines_were_deleted, first_deleted, last_deleted = return_flags
 
     if not lines_were_deleted and not cut_quotations:
-        return None
+        return msg_body
 
     if lines_were_deleted:
         #collect checkpoints from deleted lines
@@ -495,7 +520,7 @@ def extract_from_html_tree(html_tree):
         )
 
     if _readable_text_empty(html_tree_copy):
-        return None
+        return msg_body
 
     # NOTE: We remove_namespaces() because we are using an HTML5 Parser, HTML
     # parsers do not recognize namespaces in HTML tags. As such the rendered
@@ -521,11 +546,7 @@ def extract_from_html_tree(html_tree):
     #    of replacing data outside the <tag> which might be essential to
     #    the customer.
     remove_namespaces(html_tree_copy)
-    s = html.tostring(html_tree_copy, encoding="ascii")
+    return html.tostring(html_tree_copy)
-    if not s:
-        return None
-
-    return s.decode("ascii")
 
 
 def remove_namespaces(root):
@@ -644,10 +665,10 @@ def _readable_text_empty(html_tree):
 
 
 def is_splitter(line):
-    """
+    '''
     Returns Matcher object if provided string is a splitter and
     None otherwise.
-    """
+    '''
     for pattern in SPLITTER_PATTERNS:
         matcher = re.match(pattern, line)
         if matcher:
@@ -655,12 +676,12 @@ def is_splitter(line):
 
 
 def text_content(context):
-    """XPath Extension function to return a node text content."""
+    '''XPath Extension function to return a node text content.'''
     return context.context_node.xpath("string()").strip()
 
 
 def tail(context):
-    """XPath Extension function to return a node tail text."""
+    '''XPath Extension function to return a node tail text.'''
     return context.context_node.tail or ''
 
 

talon/signature/__init__.py

@@ -23,14 +23,17 @@ trained against, don't forget to regenerate:
 from __future__ import absolute_import
 import os
 
-from talon.signature import extraction
+from . import extraction
-from talon.signature.extraction import extract
+from . extraction import extract  #noqa
-from talon.signature.learning import classifier
+from . learning import classifier
+
+
+DATA_DIR = os.path.join(os.path.dirname(__file__), 'data')
+
+EXTRACTOR_FILENAME = os.path.join(DATA_DIR, 'classifier')
+EXTRACTOR_DATA = os.path.join(DATA_DIR, 'train.data')
 
 
 def initialize():
-    data_dir = os.path.join(os.path.dirname(__file__), 'data')
+    extraction.EXTRACTOR = classifier.load(EXTRACTOR_FILENAME,
-    extractor_filename = os.path.join(data_dir, 'classifier')
+                                           EXTRACTOR_DATA)
-    extractor_data_filename = os.path.join(data_dir, 'train.data')
-    extraction.EXTRACTOR = classifier.load(extractor_filename,
-                                           extractor_data_filename)

talon/signature/bruteforce.py

@@ -62,7 +62,7 @@ RE_SIGNATURE_CANDIDATE = re.compile(r'''
 
 
 def extract_signature(msg_body):
-    '''
+    """
     Analyzes message for a presence of signature block (by common patterns)
     and returns tuple with two elements: message text without signature block
     and the signature itself.
@@ -72,7 +72,7 @@ def extract_signature(msg_body):
 
     >>> extract_signature('Hey man!')
     ('Hey man!', None)
-    '''
+    """
     try:
         # identify line delimiter first
         delimiter = get_delimiter(msg_body)

talon/signature/learning/classifier.py

@@ -8,7 +8,7 @@ body belongs to the signature.
 from __future__ import absolute_import
 
 from numpy import genfromtxt
-import joblib
+from sklearn.externals import joblib
 from sklearn.svm import LinearSVC
 
 

talon/signature/learning/helpers.py

@@ -5,17 +5,21 @@
 * regexp's constants used when evaluating signature's features
 
 """
-import unicodedata
 
+from __future__ import absolute_import
+import unicodedata
 import regex as re
 
+from talon.utils import to_unicode
+
 from talon.signature.constants import SIGNATURE_MAX_LINES
 
+
 rc = re.compile
 
 RE_EMAIL = rc('\S@\S')
 RE_RELAX_PHONE = rc('(\(? ?[\d]{2,3} ?\)?.{,3}?){2,}')
-RE_URL = rc(r"""https?://|www\.[\S]+\.[\S]""")
+RE_URL = rc(r'''https?://|www\.[\S]+\.[\S]''')
 
 # Taken from:
 # http://www.cs.cmu.edu/~vitor/papers/sigFilePaper_finalversion.pdf
@@ -51,7 +55,7 @@ BAD_SENDER_NAMES = [
 
 
 def binary_regex_search(prog):
-    """Returns a function that returns 1 or 0 depending on regex search result.
+    '''Returns a function that returns 1 or 0 depending on regex search result.
 
     If regular expression compiled into prog is present in a string
     the result of calling the returned function with the string will be 1
@@ -62,12 +66,12 @@ def binary_regex_search(prog):
     1
     >>> binary_regex_search(re.compile("12"))("34")
     0
-    """
+    '''
     return lambda s: 1 if prog.search(s) else 0
 
 
 def binary_regex_match(prog):
-    """Returns a function that returns 1 or 0 depending on regex match result.
+    '''Returns a function that returns 1 or 0 depending on regex match result.
 
     If a string matches regular expression compiled into prog
     the result of calling the returned function with the string will be 1
@@ -78,7 +82,7 @@ def binary_regex_match(prog):
     1
     >>> binary_regex_match(re.compile("12"))("3 12")
     0
-    """
+    '''
     return lambda s: 1 if prog.match(s) else 0
 
 
@@ -98,7 +102,7 @@ def flatten_list(list_to_flatten):
 
 
 def contains_sender_names(sender):
-    """Returns a functions to search sender\'s name or it\'s part.
+    '''Returns a functions to search sender\'s name or it\'s part.
 
     >>> feature = contains_sender_names("Sergey N.  Obukhov <xxx@example.com>")
     >>> feature("Sergey Obukhov")
@@ -111,7 +115,7 @@ def contains_sender_names(sender):
     1
     >>> contains_sender_names("<serobnic@mail.ru>")("serobnic")
     1
-    """
+    '''
     names = '( |$)|'.join(flatten_list([[e, e.capitalize()]
                                         for e in extract_names(sender)]))
     names = names or sender
@@ -131,25 +135,20 @@ def extract_names(sender):
     >>> extract_names('')
     []
     """
+    sender = to_unicode(sender, precise=True)
     # Remove non-alphabetical characters
     sender = "".join([char if char.isalpha() else ' ' for char in sender])
     # Remove too short words and words from "black" list i.e.
     # words like `ru`, `gmail`, `com`, `org`, etc.
-    names = list()
+    sender = [word for word in sender.split() if len(word) > 1 and
-    for word in sender.split():
+              not word in BAD_SENDER_NAMES]
-        if len(word) < 2:
+    # Remove duplicates
-            continue
+    names = list(set(sender))
-        if word in BAD_SENDER_NAMES:
-            continue
-        if word in names:
-            continue
-        names.append(word)
-
     return names
 
 
 def categories_percent(s, categories):
-    """Returns category characters percent.
+    '''Returns category characters percent.
 
     >>> categories_percent("qqq ggg hhh", ["Po"])
     0.0
@@ -161,8 +160,9 @@ def categories_percent(s, categories):
     50.0
     >>> categories_percent("s.s,5s", ["Po", "Nd"])
     50.0
-    """
+    '''
     count = 0
+    s = to_unicode(s, precise=True)
     for c in s:
         if unicodedata.category(c) in categories:
             count += 1
@@ -170,18 +170,19 @@ def categories_percent(s, categories):
 
 
 def punctuation_percent(s):
-    """Returns punctuation percent.
+    '''Returns punctuation percent.
 
     >>> punctuation_percent("qqq ggg hhh")
     0.0
     >>> punctuation_percent("q,w.")
     50.0
-    """
+    '''
     return categories_percent(s, ['Po'])
 
 
 def capitalized_words_percent(s):
-    """Returns capitalized words percent."""
+    '''Returns capitalized words percent.'''
+    s = to_unicode(s, precise=True)
     words = re.split('\s', s)
     words = [w for w in words if w.strip()]
     words = [w for w in words if len(w) > 2]    
@@ -207,26 +208,20 @@ def many_capitalized_words(s):
 
 
 def has_signature(body, sender):
-    """Checks if the body has signature. Returns True or False."""
+    '''Checks if the body has signature. Returns True or False.'''
     non_empty = [line for line in body.splitlines() if line.strip()]
     candidate = non_empty[-SIGNATURE_MAX_LINES:]
     upvotes = 0
-    sender_check = contains_sender_names(sender)
     for line in candidate:
         # we check lines for sender's name, phone, email and url,
         # those signature lines don't take more then 27 lines
         if len(line.strip()) > 27:
             continue
-
+        elif contains_sender_names(sender)(line):
-        if sender_check(line):
             return True
-
+        elif (binary_regex_search(RE_RELAX_PHONE)(line) +
-        if (binary_regex_search(RE_RELAX_PHONE)(line) +
               binary_regex_search(RE_EMAIL)(line) +
               binary_regex_search(RE_URL)(line) == 1):
             upvotes += 1
-
     if upvotes > 1:
         return True
-
-    return False

talon/utils.py

@@ -1,17 +1,110 @@
 # coding:utf-8
-from __future__ import annotations
 
+from __future__ import absolute_import
+
+from random import shuffle
+
+import cchardet
+import chardet
 import html5lib
 import regex as re
-from html5lib import HTMLParser
+import six
 from lxml.cssselect import CSSSelector
-from lxml.etree import _Element
 from lxml.html import html5parser
 
 from talon.constants import RE_DELIMITER
 
 
-def get_delimiter(msg_body: str) -> str:
+def safe_format(format_string, *args, **kwargs):
+    """
+    Helper: formats string with any combination of bytestrings/unicode
+    strings without raising exceptions
+    """
+    try:
+        if not args and not kwargs:
+            return format_string
+        else:
+            return format_string.format(*args, **kwargs)
+
+    # catch encoding errors and transform everything into utf-8 string
+    # before logging:
+    except (UnicodeEncodeError, UnicodeDecodeError):
+        format_string = to_utf8(format_string)
+        args = [to_utf8(p) for p in args]
+        kwargs = {k: to_utf8(v) for k, v in six.iteritems(kwargs)}
+        return format_string.format(*args, **kwargs)
+
+    # ignore other errors
+    except:
+        return u''
+
+
+def to_unicode(str_or_unicode, precise=False):
+    """
+    Safely returns a unicode version of a given string
+    >>> utils.to_unicode('привет')
+        u'привет'
+    >>> utils.to_unicode(u'привет')
+        u'привет'
+    If `precise` flag is True, tries to guess the correct encoding first.
+    """
+    if not isinstance(str_or_unicode, six.text_type):
+        encoding = quick_detect_encoding(str_or_unicode) if precise else 'utf-8'
+        return six.text_type(str_or_unicode, encoding, 'replace')
+    return str_or_unicode
+
+
+def detect_encoding(string):
+    """
+    Tries to detect the encoding of the passed string.
+
+    Defaults to UTF-8.
+    """
+    assert isinstance(string, bytes)
+    try:
+        detected = chardet.detect(string)
+        if detected:
+            return detected.get('encoding') or 'utf-8'
+    except Exception as e:
+        pass
+    return 'utf-8'
+
+
+def quick_detect_encoding(string):
+    """
+    Tries to detect the encoding of the passed string.
+
+    Uses cchardet. Fallbacks to detect_encoding.
+    """
+    assert isinstance(string, bytes)
+    try:
+        detected = cchardet.detect(string)
+        if detected:
+            return detected.get('encoding') or detect_encoding(string)
+    except Exception as e:
+        pass
+    return detect_encoding(string)
+
+
+def to_utf8(str_or_unicode):
+    """
+    Safely returns a UTF-8 version of a given string
+    >>> utils.to_utf8(u'hi')
+        'hi'
+    """
+    if not isinstance(str_or_unicode, six.text_type):
+        return str_or_unicode.encode("utf-8", "ignore")
+    return str(str_or_unicode)
+
+
+def random_token(length=7):
+    vals = ("a b c d e f g h i j k l m n o p q r s t u v w x y z "
+            "0 1 2 3 4 5 6 7 8 9").split(' ')
+    shuffle(vals)
+    return ''.join(vals[:length])
+
+
+def get_delimiter(msg_body):
     delimiter = RE_DELIMITER.search(msg_body)
     if delimiter:
         delimiter = delimiter.group()
@@ -21,7 +114,7 @@ def get_delimiter(msg_body: str) -> str:
     return delimiter
 
 
-def html_tree_to_text(tree: _Element) -> str:
+def html_tree_to_text(tree):
     for style in CSSSelector('style')(tree):
         style.getparent().remove(style)
 
@@ -53,22 +146,26 @@ def html_tree_to_text(tree: _Element) -> str:
             not text.endswith("\n") and not el_text):
             text += "\n"
 
-    text = _rm_excessive_newlines(text)
+    retval = _rm_excessive_newlines(text)
-    return text
+    return _encode_utf8(retval)
 
 
-def html_to_text(s: str) -> str | None:
+def html_to_text(string):
     """
     Dead-simple HTML-to-text converter:
         >>> html_to_text("one<br>two<br>three")
-        <<< "one\ntwo\nthree"
+        >>> "one\ntwo\nthree"
 
     NOTES:
         1. the string is expected to contain UTF-8 encoded HTML!
+        2. returns utf-8 encoded str (not unicode)
         3. if html can't be parsed returns None
     """
-    s = _prepend_utf8_declaration(s)
+    if isinstance(string, six.text_type):
-    s = s.replace("\n", "")
+        string = string.encode('utf8')
+
+    s = _prepend_utf8_declaration(string)
+    s = s.replace(b"\n", b"")
     tree = html_fromstring(s)
 
     if tree is None:
@@ -77,46 +174,74 @@ def html_to_text(s: str) -> str | None:
     return html_tree_to_text(tree)
 
 
-def html_fromstring(s: str) -> _Element:
+def html_fromstring(s):
     """Parse html tree from string. Return None if the string can't be parsed.
     """
+    if isinstance(s, six.text_type):
+        s = s.encode('utf8')
+    try:
+        if html_too_big(s):
+            return None
+
         return html5parser.fromstring(s, parser=_html5lib_parser())
+    except Exception:
+        pass
 
 
-def html_document_fromstring(s: str) -> _Element:
+def html_document_fromstring(s):
     """Parse html tree from string. Return None if the string can't be parsed.
     """
+    if isinstance(s, six.text_type):
+        s = s.encode('utf8')
+    try:
+        if html_too_big(s):
+            return None
+
         return html5parser.document_fromstring(s, parser=_html5lib_parser())
+    except Exception:
+        pass
 
 
-def cssselect(expr: str, tree: str) -> list[_Element]:
+def cssselect(expr, tree):
     return CSSSelector(expr)(tree)
 
 
-def _contains_charset_spec(s: str) -> str:
+def html_too_big(s):
+    if isinstance(s, six.text_type):
+        s = s.encode('utf8')
+    return s.count(b'<') > _MAX_TAGS_COUNT
+
+
+def _contains_charset_spec(s):
     """Return True if the first 4KB contain charset spec
     """
-    return s.lower().find('html; charset=', 0, 4096) != -1
+    return s.lower().find(b'html; charset=', 0, 4096) != -1
 
 
-def _prepend_utf8_declaration(s: str) -> str:
+def _prepend_utf8_declaration(s):
     """Prepend 'utf-8' encoding declaration if the first 4KB don't have any
     """
     return s if _contains_charset_spec(s) else _UTF8_DECLARATION + s
 
 
-def _rm_excessive_newlines(s: str) -> str:
+def _rm_excessive_newlines(s):
     """Remove excessive newlines that often happen due to tons of divs
     """
     return _RE_EXCESSIVE_NEWLINES.sub("\n\n", s).strip()
 
 
-def _html5lib_parser() -> HTMLParser:
+def _encode_utf8(s):
+    """Encode in 'utf-8' if unicode
+    """
+    return s.encode('utf-8') if isinstance(s, six.text_type) else s
+
+
+def _html5lib_parser():
     """
     html5lib is a pure-python library that conforms to the WHATWG HTML spec
     and is not vulnarable to certain attacks common for XML libraries
     """
-    return HTMLParser(
+    return html5lib.HTMLParser(
         # build lxml tree
         html5lib.treebuilders.getTreeBuilder("lxml"),
         # remove namespace value from inside lxml.html.html5paser element tag
@@ -126,10 +251,14 @@ def _html5lib_parser() -> HTMLParser:
     )
 
 
-_UTF8_DECLARATION = ('<meta http-equiv="Content-Type" content="text/html;'
+_UTF8_DECLARATION = (b'<meta http-equiv="Content-Type" content="text/html;'
-                     'charset=utf-8">')
+                     b'charset=utf-8">')
 
 _BLOCKTAGS = ['div', 'p', 'ul', 'li', 'h1', 'h2', 'h3']
 _HARDBREAKS = ['br', 'hr', 'tr']
 
 _RE_EXCESSIVE_NEWLINES = re.compile("\n{2,10}")
+
+# an extensive research shows that exceeding this limit
+# might lead to excessive processing time
+_MAX_TAGS_COUNT = 419

test-requirements.txt

@@ -1,3 +0,0 @@
-coverage
-mock
-nose>=1.2.1

tests/__init__.py

@@ -1,6 +1,4 @@
 from __future__ import absolute_import
-from nose.tools import *
-from mock import *
 
 import talon
 

tests/html_quotations_test.py

@@ -2,19 +2,14 @@
 
 from __future__ import absolute_import
 
-# noinspection PyUnresolvedReferences
+from tests.fixtures import REPLY_QUOTATIONS_SHARE_BLOCK, OLK_SRC_BODY_SECTION, REPLY_SEPARATED_BY_HR
-import re
+from nose.tools import eq_, ok_, assert_false, assert_true
-from unittest.mock import Mock, patch
-
-from nose.tools import assert_false, assert_true, eq_, ok_
-
-from tests.fixtures import (OLK_SRC_BODY_SECTION,
-                            REPLY_QUOTATIONS_SHARE_BLOCK,
-                            REPLY_SEPARATED_BY_HR)
 from talon import quotations, utils as u
+from mock import Mock, patch
+import re
 
-RE_WHITESPACE = re.compile(r"\s")
+RE_WHITESPACE = re.compile("\s")
-RE_DOUBLE_WHITESPACE = re.compile(r"\s")
+RE_DOUBLE_WHITESPACE = re.compile("\s")
 
 
 def test_quotation_splitter_inside_blockquote():
@@ -169,7 +164,7 @@ def test_unicode_in_reply():
 
 <blockquote>
   Quote
-</blockquote>"""
+</blockquote>""".encode("utf-8")
 
     eq_("<html><head></head><body>Reply&#160;&#160;Text<br><div><br></div>"
         "</body></html>",
@@ -317,6 +312,7 @@ def extract_reply_and_check(filename):
     msg_body = f.read()
     reply = quotations.extract_from_html(msg_body)
     plain_reply = u.html_to_text(reply)
+    plain_reply = plain_reply.decode('utf8')
 
     eq_(RE_WHITESPACE.sub('', "Hi. I am fine.\n\nThanks,\nAlex"),
         RE_WHITESPACE.sub('', plain_reply))
@@ -393,6 +389,18 @@ def test_gmail_forwarded_msg():
     eq_(RE_WHITESPACE.sub('', msg_body), RE_WHITESPACE.sub('', extracted))
 
 
+@patch.object(u, '_MAX_TAGS_COUNT', 4)
+def test_too_large_html():
+    msg_body = 'Reply' \
+               '<div class="gmail_quote">' \
+               '<div class="gmail_quote">On 11-Apr-2011, at 6:54 PM, Bob &lt;bob@example.com&gt; wrote:' \
+               '<div>Test</div>' \
+               '</div>' \
+               '</div>'
+    eq_(RE_WHITESPACE.sub('', msg_body),
+        RE_WHITESPACE.sub('', quotations.extract_from_html(msg_body)))
+
+
 def test_readable_html_empty():
     msg_body = """
 <blockquote>

tests/quotations_test.py

@@ -1,10 +1,10 @@
 # -*- coding: utf-8 -*-
 
 from __future__ import absolute_import
-from . import *
-from . fixtures import *
 
+from mock import Mock, patch
 from talon import quotations
+from nose.tools import eq_
 
 
 @patch.object(quotations, 'extract_from_html')

tests/signature/bruteforce_test.py

@@ -1,9 +1,10 @@
 # -*- coding: utf-8 -*-
 
 from __future__ import absolute_import
-from .. import *
+from nose.tools import eq_
 
 from talon.signature import bruteforce
+from mock import patch, Mock
 
 
 def test_empty_body():

tests/signature/extraction_test.py

@@ -2,14 +2,14 @@
 
 from __future__ import absolute_import
 
-import os
-
-from six.moves import range
-
 from talon.signature import bruteforce, extraction, extract
 from talon.signature import extraction as e
 from talon.signature.learning import dataset
-from .. import *
+from nose.tools import eq_
+from .. import STRIPPED, UNICODE_MSG
+from six.moves import range
+from mock import patch
+import os
 
 
 def test_message_shorter_SIGNATURE_MAX_LINES():

tests/signature/learning/dataset_test.py

@@ -1,14 +1,13 @@
 # -*- coding: utf-8 -*-
 
 from __future__ import absolute_import
-from ... import *
-import os
-
-from numpy import genfromtxt
-
-from talon.signature.learning import dataset as d
 
+from ... import EML_MSG_FILENAME, MSG_FILENAME_WITH_BODY_SUFFIX, TMP_DIR, EMAILS_DIR
 from talon.signature.learning.featurespace import features
+from talon.signature.learning import dataset as d
+from nose.tools import eq_, assert_false, ok_
+from numpy import genfromtxt
+import os
 
 
 def test_is_sender_filename():

tests/signature/learning/featurespace_test.py

@@ -1,9 +1,10 @@
 # -*- coding: utf-8 -*-
 
 from __future__ import absolute_import
-from ... import *
 
 from talon.signature.learning import featurespace as fs
+from nose.tools import eq_, assert_false, ok_
+from mock import patch
 
 
 def test_apply_features():

tests/signature/learning/helpers_test.py

@@ -1,13 +1,13 @@
 # -*- coding: utf-8 -*-
 
 from __future__ import absolute_import
-from ... import *
-
-import regex as re
 
 from talon.signature.learning import helpers as h
-from talon.signature.learning.helpers import *
+from talon.signature.learning.helpers import RE_RELAX_PHONE, RE_NAME
+from nose.tools import eq_, ok_, assert_false, assert_in
+from mock import patch, Mock
 from six.moves import range
+import re
 
 # First testing regex constants.
 VALID = '''

tests/text_quotations_test.py

@@ -1,16 +1,15 @@
 # -*- coding: utf-8 -*-
 
 from __future__ import absolute_import
-from . import *
-from . fixtures import *
 
-import os
+from tests.fixtures import STANDARD_REPLIES
-
-import email.iterators
 from talon import quotations
-import six
 from six.moves import range
-from six import StringIO
+from nose.tools import eq_
+from mock import patch
+import email.iterators
+import six
+import os
 
 
 @patch.object(quotations, 'MAX_LINES_COUNT', 1)
@@ -35,6 +34,7 @@ On 11-Apr-2011, at 6:54 PM, Roman Tkachenko <romant@example.com> wrote:
 
     eq_("Test reply", quotations.extract_from_plain(msg_body))
 
+
 def test_pattern_on_date_polymail():
     msg_body = """Test reply
 
@@ -190,14 +190,17 @@ Test"""
     eq_('Test reply', quotations.extract_from_plain(
         msg_body.format(six.text_type(original_message_indicator))))
 
+
 def test_english_original_message():
     _check_pattern_original_message('Original Message')
     _check_pattern_original_message('Reply Message')
 
+
 def test_german_original_message():
     _check_pattern_original_message(u'Ursprüngliche Nachricht')
     _check_pattern_original_message('Antwort Nachricht')
 
+
 def test_danish_original_message():
     _check_pattern_original_message('Oprindelig meddelelse')
 
@@ -296,6 +299,7 @@ On 04/19/2011 07:10 AM, Roman Tkachenko wrote:
 > Hello"""
     eq_("Hi", quotations.extract_from_plain(msg_body))
 
+
 def test_with_indent():
     msg_body = """YOLO salvia cillum kogi typewriter mumblecore cardigan skateboard Austin.
 
@@ -303,7 +307,8 @@ def test_with_indent():
 
 Brunch mumblecore pug Marfa tofu, irure taxidermy hoodie readymade pariatur.
     """
-    eq_("YOLO salvia cillum kogi typewriter mumblecore cardigan skateboard Austin.", quotations.extract_from_plain(msg_body))
+    eq_("YOLO salvia cillum kogi typewriter mumblecore cardigan skateboard Austin.",
+        quotations.extract_from_plain(msg_body))
 
 
 def test_short_quotation_with_newline():
@@ -343,6 +348,7 @@ Subject: The manager has commented on your Loop
 Blah-blah-blah
 """))
 
+
 def test_german_from_block():
     eq_('Allo! Follow up MIME!', quotations.extract_from_plain(
     """Allo! Follow up MIME!
@@ -355,6 +361,7 @@ Betreff: The manager has commented on your Loop
 Blah-blah-blah
 """))
 
+
 def test_french_multiline_from_block():
     eq_('Lorem ipsum', quotations.extract_from_plain(
     u"""Lorem ipsum
@@ -367,6 +374,7 @@ Objet : Follow Up
 Blah-blah-blah
 """))
 
+
 def test_french_from_block():
     eq_('Lorem ipsum', quotations.extract_from_plain(
     u"""Lorem ipsum
@@ -375,6 +383,7 @@ Le 23 janv. 2015 à 22:03, Brendan xxx <brendan.xxx@xxx.com<mailto:brendan.xxx@x
 
 Bonjour!"""))
 
+
 def test_polish_from_block():
     eq_('Lorem ipsum', quotations.extract_from_plain(
     u"""Lorem ipsum
@@ -385,6 +394,7 @@ napisał:
 Blah!
 """))
 
+
 def test_danish_from_block():
     eq_('Allo! Follow up MIME!', quotations.extract_from_plain(
     """Allo! Follow up MIME!
@@ -397,6 +407,7 @@ Emne: The manager has commented on your Loop
 Blah-blah-blah
 """))
 
+
 def test_swedish_from_block():
     eq_('Allo! Follow up MIME!', quotations.extract_from_plain(
     u"""Allo! Follow up MIME!
@@ -408,6 +419,7 @@ Till: Isacson Leiff
 Blah-blah-blah
 """))
 
+
 def test_swedish_from_line():
     eq_('Lorem', quotations.extract_from_plain(
     """Lorem
@@ -416,6 +428,7 @@ Den 14 september, 2015 02:23:18, Valentino Rudy (valentino@rudy.be) skrev:
 Veniam laborum mlkshk kale chips authentic. Normcore mumblecore laboris, fanny pack readymade eu blog chia pop-up freegan enim master cleanse.
 """))
 
+
 def test_norwegian_from_line():
     eq_('Lorem', quotations.extract_from_plain(
     u"""Lorem
@@ -424,6 +437,7 @@ På 14 september 2015 på 02:23:18, Valentino Rudy (valentino@rudy.be) skrev:
 Veniam laborum mlkshk kale chips authentic. Normcore mumblecore laboris, fanny pack readymade eu blog chia pop-up freegan enim master cleanse.
 """))
 
+
 def test_dutch_from_block():
     eq_('Gluten-free culpa lo-fi et nesciunt nostrud.', quotations.extract_from_plain(
     """Gluten-free culpa lo-fi et nesciunt nostrud.
@@ -433,6 +447,7 @@ Op 17-feb.-2015, om 13:18 heeft Julius Caesar <pantheon@rome.com> het volgende g
 Small batch beard laboris tempor, non listicle hella Tumblr heirloom.
 """))
 
+
 def test_vietnamese_from_block():
     eq_('Hello', quotations.extract_from_plain(
     u"""Hello
@@ -442,6 +457,7 @@ Vào 14:24 8 tháng 6, 2017, Hùng Nguyễn <hungnguyen@xxx.com> đã viết:
 > Xin chào
 """))
 
+
 def test_quotation_marker_false_positive():
     msg_body = """Visit us now for assistance...
 >>> >>>  http://www.domain.com <<<
@@ -826,10 +842,10 @@ The user experience was unparallelled. Please continue production. I'm sending p
 that this line is intact."""
 
     parsed = quotations.extract_from_plain(msg_body)
-    eq_(msg_body, parsed)
+    eq_(msg_body, parsed.decode('utf8'))
 
 
-def test_appointment_2():
+def test_appointment():
     msg_body = """Invitation for an interview:
 
 Date: Wednesday 3, October 2011 
@@ -838,4 +854,4 @@ Address: 130 Fox St
 
 Please bring in your ID."""
     parsed = quotations.extract_from_plain(msg_body)
-    eq_(msg_body, parsed)
+    eq_(msg_body, parsed.decode('utf8'))

tests/utils_test.py

@@ -2,8 +2,12 @@
 
 from __future__ import absolute_import
 
+
+from nose.tools import eq_, ok_, assert_false
 from talon import utils as u
-from . import *
+from mock import patch, Mock
+import cchardet
+import six
 
 
 def test_get_delimiter():
@@ -12,6 +16,58 @@ def test_get_delimiter():
     eq_('\n', u.get_delimiter('abc'))
 
 
+def test_unicode():
+    eq_(u'hi', u.to_unicode('hi'))
+    eq_(type(u.to_unicode('hi')), six.text_type)
+    eq_(type(u.to_unicode(u'hi')), six.text_type)
+    eq_(type(u.to_unicode('привет')), six.text_type)
+    eq_(type(u.to_unicode(u'привет')), six.text_type)
+    eq_(u"привет", u.to_unicode('привет'))
+    eq_(u"привет", u.to_unicode(u'привет'))
+    # some latin1 stuff
+    eq_(u"Versión", u.to_unicode(u'Versi\xf3n'.encode('iso-8859-2'), precise=True))
+
+
+def test_detect_encoding():
+    eq_('ascii', u.detect_encoding(b'qwe').lower())
+    ok_(u.detect_encoding(
+        u'Versi\xf3n'.encode('iso-8859-2')).lower() in [
+            'iso-8859-1', 'iso-8859-2'])
+    eq_('utf-8', u.detect_encoding(u'привет'.encode('utf8')).lower())
+    # fallback to utf-8
+    with patch.object(u.chardet, 'detect') as detect:
+        detect.side_effect = Exception
+        eq_('utf-8', u.detect_encoding('qwe'.encode('utf8')).lower())
+
+
+def test_quick_detect_encoding():
+    eq_('ascii', u.quick_detect_encoding(b'qwe').lower())
+    ok_(u.quick_detect_encoding(
+        u'Versi\xf3n'.encode('windows-1252')).lower() in [
+            'windows-1252', 'windows-1250'])
+    eq_('utf-8', u.quick_detect_encoding(u'привет'.encode('utf8')).lower())
+
+
+@patch.object(cchardet, 'detect')
+@patch.object(u, 'detect_encoding')
+def test_quick_detect_encoding_edge_cases(detect_encoding, cchardet_detect):
+    cchardet_detect.return_value = {'encoding': 'ascii'}
+    eq_('ascii', u.quick_detect_encoding(b"qwe"))
+    cchardet_detect.assert_called_once_with(b"qwe")
+
+    # fallback to detect_encoding
+    cchardet_detect.return_value = {}
+    detect_encoding.return_value = 'utf-8'
+    eq_('utf-8', u.quick_detect_encoding(b"qwe"))
+
+    # exception
+    detect_encoding.reset_mock()
+    cchardet_detect.side_effect = Exception()
+    detect_encoding.return_value = 'utf-8'
+    eq_('utf-8', u.quick_detect_encoding(b"qwe"))
+    ok_(detect_encoding.called)
+
+
 def test_html_to_text():
     html = """<body>
 <p>Hello world!</p>
@@ -25,11 +81,11 @@ Haha
 </p>
 </body>"""
     text = u.html_to_text(html)
-    eq_("Hello world! \n\n  * One! \n  * Two \nHaha", text)
+    eq_(b"Hello world! \n\n  * One! \n  * Two \nHaha", text)
-    eq_(u"привет!", u.html_to_text("<b>привет!</b>"))
+    eq_(u"привет!", u.html_to_text("<b>привет!</b>").decode('utf8'))
 
     html = '<body><br/><br/>Hi</body>'
-    eq_('Hi', u.html_to_text(html))
+    eq_(b'Hi', u.html_to_text(html))
 
     html = """Hi
 <style type="text/css">
@@ -49,23 +105,60 @@ font: 13px 'Lucida Grande', Arial, sans-serif;
 
 }
 </style>"""
-    eq_('Hi', u.html_to_text(html))
+    eq_(b'Hi', u.html_to_text(html))
 
     html = """<div>
 <!-- COMMENT 1 -->
 <span>TEXT 1</span>
 <p>TEXT 2 <!-- COMMENT 2 --></p>
 </div>"""
-    eq_('TEXT 1 \nTEXT 2', u.html_to_text(html))
+    eq_(b'TEXT 1 \nTEXT 2', u.html_to_text(html))
 
 
 def test_comment_no_parent():
-    s = '<!-- COMMENT 1 --> no comment'
+    s = b'<!-- COMMENT 1 --> no comment'
     d = u.html_document_fromstring(s)
-    eq_("no comment", u.html_tree_to_text(d))
+    eq_(b"no comment", u.html_tree_to_text(d))
+
+
+@patch.object(u.html5parser, 'fromstring', Mock(side_effect=Exception()))
+def test_html_fromstring_exception():
+    eq_(None, u.html_fromstring("<html></html>"))
+
+
+@patch.object(u, 'html_too_big', Mock())
+@patch.object(u.html5parser, 'fromstring')
+def test_html_fromstring_too_big(fromstring):
+    eq_(None, u.html_fromstring("<html></html>"))
+    assert_false(fromstring.called)
+
+
+@patch.object(u.html5parser, 'document_fromstring')
+def test_html_document_fromstring_exception(document_fromstring):
+    document_fromstring.side_effect = Exception()
+    eq_(None, u.html_document_fromstring("<html></html>"))
+
+
+@patch.object(u, 'html_too_big', Mock())
+@patch.object(u.html5parser, 'document_fromstring')
+def test_html_document_fromstring_too_big(document_fromstring):
+    eq_(None, u.html_document_fromstring("<html></html>"))
+    assert_false(document_fromstring.called)
 
 
 @patch.object(u, 'html_fromstring', Mock(return_value=None))
 def test_bad_html_to_text():
     bad_html = "one<br>two<br>three"
     eq_(None, u.html_to_text(bad_html))
+
+
+@patch.object(u, '_MAX_TAGS_COUNT', 3)
+def test_html_too_big():
+    eq_(False, u.html_too_big("<div></div>"))
+    eq_(True, u.html_too_big("<div><span>Hi</span></div>"))
+
+
+@patch.object(u, '_MAX_TAGS_COUNT', 3)
+def test_html_to_text():
+    eq_(b"Hello", u.html_to_text("<div>Hello</div>"))
+    eq_(None, u.html_to_text("<div><span>Hi</span></div>"))