Drops Python 2 support

REP-1030

In addition to some python 2 => 3 fixes, this change bumps the scikit-learn
version to latest. The previously pinned version of scikit-learn failed trying
to compile all necessary C modules under python 3.7+ due to included header files
that weren't compatible with C the API implemented in python 3.7+.

Simultaneously, with the restrictive compatibility supported by scikit-learn,
it seemed prudent to drop python 2 support altogether. Otherwise, we'd be stuck
with python 3.4 as the newest possible version we could support.

With this change, tests are currently passing under 3.9.2.

Lastly, imports the original training data. At some point, a new version
of the training data was committed to the repo but no classifier was
trained from it. Using a classifier trained from this new data resulted
in most of the tests failing.

.build/Dockerfile

@@ -0,0 +1,20 @@
+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

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

MANIFEST.in

@@ -5,3 +5,10 @@ include classifier
 include LICENSE
 include MANIFEST.in
 include README.rst
+include talon/signature/data/train.data
+include talon/signature/data/classifier
+include talon/signature/data/classifier_01.npy
+include talon/signature/data/classifier_02.npy
+include talon/signature/data/classifier_03.npy
+include talon/signature/data/classifier_04.npy
+include talon/signature/data/classifier_05.npy

requirements.txt

@@ -0,0 +1,11 @@
+chardet>=1.0.1
+cchardet>=0.3.5
+cssselect
+html5lib
+joblib
+lxml>=2.3.3
+numpy
+regex>=1
+scikit-learn==0.24.1 # pickled versions of classifier, else rebuild
+scipy
+six>=1.10.0

run_tests.sh

@@ -0,0 +1,4 @@
+#!/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

@@ -19,17 +19,17 @@ class InstallCommand(install):
         if self.no_ml:
             dist = self.distribution
             dist.packages=find_packages(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(name='talon',
-      version='1.4.7',
+      version='1.4.8',
       description=("Mailgun library "
                    "to extract message quotations and signatures."),
       long_description=open("README.rst").read(),
@@ -48,12 +48,13 @@ setup(name='talon',
           "regex>=1",
           "numpy",
           "scipy",
-          "scikit-learn>=0.16.1", # pickled versions of classifier, else rebuild
+          "scikit-learn==0.24.1", # pickled versions of classifier, else rebuild
-          'chardet>=1.0.1',
+          "chardet>=1.0.1",
-          'cchardet>=0.3.5',
+          "cchardet>=0.3.5",
-          'cssselect',
+          "cssselect",
-          'six>=1.10.0',
+          "six>=1.10.0",
-          'html5lib'
+          "html5lib",
+          "joblib",
           ],
       tests_require=[
           "mock",

talon/quotations.py

@@ -457,7 +457,7 @@ def _extract_from_html(msg_body):
 
     msg_body = msg_body.replace(b'\r\n', b'\n')
 
-    msg_body = re.sub(r"\<\?xml.+\?\>|\<\!DOCTYPE.+]\>", "", msg_body)
+    msg_body = re.sub(br"\<\?xml.+\?\>|\<\!DOCTYPE.+]\>", "", msg_body)
 
     html_tree = html_document_fromstring(msg_body)
 
@@ -516,9 +516,69 @@ def _extract_from_html(msg_body):
     if _readable_text_empty(html_tree_copy):
         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
+    # HTML tags are no longer recognizable HTML tags. Example: <o:p> becomes
+    # <oU0003Ap>. When we port this to golang we should look into using an
+    # XML Parser NOT and HTML5 Parser since we do not know what input a
+    # customer will send us. Switching to a common XML parser in python
+    # opens us up to a host of vulnerabilities.
+    # See https://docs.python.org/3/library/xml.html#xml-vulnerabilities
+    #
+    # The down sides to removing the namespaces is that customers might
+    # judge the XML namespaces important. If that is the case then support
+    # should encourage customers to preform XML parsing of the un-stripped
+    # body to get the full unmodified XML payload.
+    #
+    # Alternatives to this approach are
+    # 1. Ignore the U0003A in tag names and let the customer deal with it.
+    #    This is not ideal, as most customers use stripped-html for viewing
+    #    emails sent from a recipient, as such they cannot control the HTML
+    #    provided by a recipient.
+    # 2. Preform a string replace of 'U0003A' to ':' on the rendered HTML
+    #    string. While this would solve the issue simply, it runs the risk
+    #    of replacing data outside the <tag> which might be essential to
+    #    the customer.
+    remove_namespaces(html_tree_copy)
     return html.tostring(html_tree_copy)
 
 
+def remove_namespaces(root):
+    """
+    Given the root of an HTML document iterate through all the elements
+    and remove any namespaces that might have been provided and remove
+    any attributes that contain a namespace
+
+    <html xmlns:o="urn:schemas-microsoft-com:office:office">
+    becomes
+    <html>
+
+    <o:p>Hi</o:p>
+    becomes
+    <p>Hi</p>
+
+    Start tags do NOT have a namespace; COLON characters have no special meaning.
+    if we don't remove the namespace the parser translates the tag name into a
+    unicode representation. For example <o:p> becomes <oU0003Ap>
+
+    See https://www.w3.org/TR/2011/WD-html5-20110525/syntax.html#start-tags
+
+
+    """
+    for child in root.iter():
+        for key, value in child.attrib.items():
+            # If the attribute includes a colon
+            if key.rfind("U0003A") != -1:
+                child.attrib.pop(key)
+
+        # If the tag includes a colon
+        idx = child.tag.rfind("U0003A")
+        if idx != -1:
+            child.tag = child.tag[idx+6:]
+
+    return root
+
+
 def split_emails(msg):
     """
     Given a message (which may consist of an email conversation thread with

talon/signature/data/__init__.py

@@ -0,0 +1 @@
+

talon/signature/learning/classifier.py

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

test-requirements.txt

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

tests/html_quotations_test.py

@@ -8,6 +8,7 @@ import re
 from talon import quotations, utils as u
 from . import *
 from .fixtures import *
+from lxml import html
 
 RE_WHITESPACE = re.compile("\s")
 RE_DOUBLE_WHITESPACE = re.compile("\s")
@@ -424,3 +425,23 @@ def test_readable_html_empty():
 def test_bad_html():
     bad_html = "<html></html>"
     eq_(bad_html, quotations.extract_from_html(bad_html))
+
+
+def test_remove_namespaces():
+    msg_body = """
+    <html xmlns:o="urn:schemas-microsoft-com:office:office" xmlns="http://www.w3.org/TR/REC-html40">
+        <body>
+            <o:p>Dear Sir,</o:p>
+            <o:p>Thank you for the email.</o:p>
+            <blockquote>thing</blockquote>
+        </body>
+    </html>
+    """
+
+    rendered = quotations.extract_from_html(msg_body)
+
+    assert_true("<p>" in rendered)
+    assert_true("xmlns" in rendered)
+
+    assert_true("<o:p>" not in rendered)
+    assert_true("<xmlns:o>" not in rendered)

tests/text_quotations_test.py

@@ -826,10 +826,10 @@ 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.decode('utf8'))
+    eq_(msg_body, parsed)
 
 
-def test_appointment():
+def test_appointment_2():
     msg_body = """Invitation for an interview:
 
 Date: Wednesday 3, October 2011 
@@ -838,4 +838,4 @@ Address: 130 Fox St
 
 Please bring in your ID."""
     parsed = quotations.extract_from_plain(msg_body)
-    eq_(msg_body, parsed.decode('utf8'))
+    eq_(msg_body, parsed)