Add some hacking checks borrowed from neutron

- [O343] Python 3: do not use basestring.
- [O344] Python 3: do not use dict.iteritems.
- [O345] Usage of Python eventlet module not allowed

Change-Id: I0d70bbc4608cc08f0944b836814462acdcf7269f

HACKING.rst

@@ -25,6 +25,9 @@ Octavia Specific Commandments
 - [O340] Don't use xrange()
 - [O341] Don't translate logs.
 - [0342] Exception messages should be translated
+- [O343] Python 3: do not use basestring.
+- [O344] Python 3: do not use dict.iteritems.
+- [O345] Usage of Python eventlet module not allowed
 
 Creating Unit Tests
 -------------------

octavia/hacking/checks.py

@@ -223,6 +223,50 @@ def check_raised_localized_exceptions(logical_line, filename):
             yield (logical_line.index(exception_msg), msg)
 
 
+def check_no_basestring(logical_line):
+    """O343 - basestring is not Python3-compatible.
+
+    :param logical_line: The logical line to check.
+    :returns: None if the logical line passes the check, otherwise a tuple
+    is yielded that contains the offending index in logical line and a
+    message describe the check validation failure.
+    """
+    if re.search(r"\bbasestring\b", logical_line):
+        msg = ("O343: basestring is not Python3-compatible, use "
+               "six.string_types instead.")
+        yield(0, msg)
+
+
+def check_python3_no_iteritems(logical_line):
+    """O344 - Use dict.items() instead of dict.iteritems().
+
+    :param logical_line: The logical line to check.
+    :returns: None if the logical line passes the check, otherwise a tuple
+    is yielded that contains the offending index in logical line and a
+    message describe the check validation failure.
+    """
+    if re.search(r".*\.iteritems\(\)", logical_line):
+        msg = ("O344: Use dict.items() instead of dict.iteritems() to be "
+               "compatible with both Python 2 and Python 3. In Python 2, "
+               "dict.items() may be inefficient for very large dictionaries. "
+               "If you can prove that you need the optimization of an "
+               "iterator for Python 2, then you can use six.iteritems(dict).")
+        yield(0, msg)
+
+
+def check_no_eventlet_imports(logical_line):
+    """O345 - Usage of Python eventlet module not allowed.
+
+    :param logical_line: The logical line to check.
+    :returns: None if the logical line passes the check, otherwise a tuple
+    is yielded that contains the offending index in logical line and a
+    message describe the check validation failure.
+    """
+    if re.match(r'(import|from)\s+[(]?eventlet', logical_line):
+        msg = 'O345 Usage of Python eventlet module not allowed'
+        yield logical_line.index('eventlet'), msg
+
+
 def factory(register):
     register(assert_true_instance)
     register(assert_equal_or_not_none)
@@ -235,3 +279,6 @@ def factory(register):
     register(no_log_warn)
     register(no_xrange)
     register(check_raised_localized_exceptions)
+    register(check_no_basestring)
+    register(check_python3_no_iteritems)
+    register(check_no_eventlet_imports)