tests: replace pycodestyle with black

Drop pycodestyle for code style checking in favor of black. Black is
much faster, stable PEP8 compliant code style checker offering also
automatic formatting. It aims to be very stable and produce smallest
diffs. It's used by many small and big projects.

Running checkstyle with black takes a few seconds with a terse output.
Thus, test-checkstyle-diff is no longer necessary.

Expand scope of checkstyle to all python files in the repo, replacing
test-checkstyle with checkstyle-python.

Also, fixstyle-python is now available for automatic style formatting.

Note: python virtualenv has been consolidated in test/Makefile,
test/requirements*.txt which will eventually be moved to a central
location.  This is required to simply the automated generation of
docker executor images in the CI.

Type: improvement
Change-Id: I022a326603485f58585e879ac0f697fceefbc9c8
Signed-off-by: Klement Sekera <klement.sekera@gmail.com>
Signed-off-by: Dave Wallace <dwallacelf@gmail.com>
diff --git a/docs/_scripts/filter_api.py b/docs/_scripts/filter_api.py
index 4848814..e22bc5e 100755
--- a/docs/_scripts/filter_api.py
+++ b/docs/_scripts/filter_api.py
@@ -24,9 +24,10 @@
 
 patterns = [
     # Search for "define" blocks and treat them as structs
-    (re.compile(r"^.*(manual_.[^\s]+\s+)?define\s+(?P<name>[^\s]+)"),
-     r"typedef struct vl_api_\g<name>_t"),
-
+    (
+        re.compile(r"^.*(manual_.[^\s]+\s+)?define\s+(?P<name>[^\s]+)"),
+        r"typedef struct vl_api_\g<name>_t",
+    ),
     # For every "brief" statement at the start of a comment block, add an
     # xref with whatever is on the same line. This gives us an index page
     # with all the API methods in one place.
@@ -36,14 +37,13 @@
     #  r'/** @xrefitem api "" "VPP API" \g<c> \g<b> \g<c>'),  # capture inline comment close
     # (re.compile(r"/\*\*\s*(?P<b>[\\@]brief)\s+(?P<c>.+)$"),
     #  r'/** @xrefitem api "" "VPP API" \g<c> \g<b> \g<c>'),
-
     # Since structs don't have params, replace @param with @tparam
-    ( re.compile("[\\@]param\\b"), "@tparam"),
+    (re.compile("[\\@]param\\b"), "@tparam"),
 ]
 
 with open(sys.argv[1]) as fd:
     for line in fd:
-        str = line[:-1] # strip \n
+        str = line[:-1]  # strip \n
         for p in patterns:
             str = p[0].sub(p[1], str)
-        sys.stdout.write(str+"\n")
+        sys.stdout.write(str + "\n")
diff --git a/docs/_scripts/filter_c.py b/docs/_scripts/filter_c.py
index 897f9f6..d3e7ee3 100755
--- a/docs/_scripts/filter_c.py
+++ b/docs/_scripts/filter_c.py
@@ -23,51 +23,82 @@
 
 replace_patterns = [
     # Search for VLIB_CLI_COMMAND, extract its parameters and add a docblock for it
-    ( re.compile("(?P<m>VLIB_CLI_COMMAND)\s*[(](?P<name>[a-zA-Z0-9_]+)[)]"),
-        r"/** @brief (@em constructor) \g<m> (\g<name>) */ vlib_cli_command_t \g<name>"),
-    ( re.compile("(?P<m>VLIB_CLI_COMMAND)\s*[(](?P<name>[a-zA-Z0-9_]+),\s*(?P<qual>[^)]*)[)]"),
-        r"/** @brief (@em constructor) \g<m> (\g<name>) */ \g<qual> vlib_cli_command_t \g<name>"),
-
+    (
+        re.compile("(?P<m>VLIB_CLI_COMMAND)\s*[(](?P<name>[a-zA-Z0-9_]+)[)]"),
+        r"/** @brief (@em constructor) \g<m> (\g<name>) */ vlib_cli_command_t \g<name>",
+    ),
+    (
+        re.compile(
+            "(?P<m>VLIB_CLI_COMMAND)\s*[(](?P<name>[a-zA-Z0-9_]+),\s*(?P<qual>[^)]*)[)]"
+        ),
+        r"/** @brief (@em constructor) \g<m> (\g<name>) */ \g<qual> vlib_cli_command_t \g<name>",
+    ),
     # Search for VLIB_REGISTER_NODE, extract its parameters and add a docblock for it
-    ( re.compile("(?P<m>VLIB_REGISTER_NODE)\s*[(](?P<name>[a-zA-Z0-9_]+)[)]"),
-        r"/** @brief (@em constructor) \g<m> (\g<name>) */ vlib_node_registration_t \g<name>"),
-    ( re.compile("(?P<m>VLIB_REGISTER_NODE)\s*[(](?P<name>[a-zA-Z0-9_]+),\s*(?P<qual>[^)]*)[)]"),
-        r"/** @brief (@em constructor) \g<m> (\g<name>) */ \g<qual> vlib_node_registration_t \g<name>"),
-
+    (
+        re.compile("(?P<m>VLIB_REGISTER_NODE)\s*[(](?P<name>[a-zA-Z0-9_]+)[)]"),
+        r"/** @brief (@em constructor) \g<m> (\g<name>) */ vlib_node_registration_t \g<name>",
+    ),
+    (
+        re.compile(
+            "(?P<m>VLIB_REGISTER_NODE)\s*[(](?P<name>[a-zA-Z0-9_]+),\s*(?P<qual>[^)]*)[)]"
+        ),
+        r"/** @brief (@em constructor) \g<m> (\g<name>) */ \g<qual> vlib_node_registration_t \g<name>",
+    ),
     # Search for VLIB_INIT_FUNCTION, extract its parameter and add a docblock for it
-    ( re.compile("(?P<m>VLIB_INIT_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+)[)]"),
-        r"/** @brief (@em constructor) \g<m> (@ref \g<name>) */ vlib_init_function_t * _vlib_init_function_\g<name>"),
-    ( re.compile("(?P<m>VLIB_DECLARE_INIT_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+)[)]"),
-        r"/** @brief (@em constructor) \g<m> (@ref \g<name>) */ vlib_init_function_t * _vlib_init_function_\g<name>"),
-
+    (
+        re.compile("(?P<m>VLIB_INIT_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+)[)]"),
+        r"/** @brief (@em constructor) \g<m> (@ref \g<name>) */ vlib_init_function_t * _vlib_init_function_\g<name>",
+    ),
+    (
+        re.compile("(?P<m>VLIB_DECLARE_INIT_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+)[)]"),
+        r"/** @brief (@em constructor) \g<m> (@ref \g<name>) */ vlib_init_function_t * _vlib_init_function_\g<name>",
+    ),
     # Search for VLIB_LOOP_ENTER_FUNCTION, extract the parameters and add a docblock for it
-    ( re.compile("(?P<m>VLIB_MAIN_LOOP_ENTER_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+)(,[^)]*)?[)]"),
-        r"/** @brief (@em constructor) \g<m> (@ref \g<name>) */ _vlib_main_loop_enter_\g<name>"),
-    ( re.compile("(?P<m>VLIB_MAIN_LOOP_EXIT_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+)(,[^)]*)?[)]"),
-        r"/** @brief (@em constructor) \g<m> (@ref \g<name>) */ _vlib_main_loop_exit_\g<name>"),
-
+    (
+        re.compile(
+            "(?P<m>VLIB_MAIN_LOOP_ENTER_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+)(,[^)]*)?[)]"
+        ),
+        r"/** @brief (@em constructor) \g<m> (@ref \g<name>) */ _vlib_main_loop_enter_\g<name>",
+    ),
+    (
+        re.compile(
+            "(?P<m>VLIB_MAIN_LOOP_EXIT_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+)(,[^)]*)?[)]"
+        ),
+        r"/** @brief (@em constructor) \g<m> (@ref \g<name>) */ _vlib_main_loop_exit_\g<name>",
+    ),
     # Search for VLIB_CONFIG_FUNCTION, extract the parameters and add a docblock for it
-    ( re.compile("(?P<m>VLIB_CONFIG_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+),\s*(?P<n>\"[^\"]+\")(,[^)]*)?[)]"),
-        r"/** @brief (@em constructor) \g<m> (\g<name>, \g<n>) */ vlib_config_function_runtime_t _vlib_config_function_\g<name>"),
-    ( re.compile("(?P<m>VLIB_EARLY_CONFIG_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+),\s*(?P<n>\"[^\"]+\")(,[^)]*)?[)]"),
-        r"/** @brief (@em constructor) \g<m> (\g<name>, \g<n>) */ vlib_config_function_runtime_t _vlib_config_function_\g<name>"),
-
+    (
+        re.compile(
+            '(?P<m>VLIB_CONFIG_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+),\s*(?P<n>"[^"]+")(,[^)]*)?[)]'
+        ),
+        r"/** @brief (@em constructor) \g<m> (\g<name>, \g<n>) */ vlib_config_function_runtime_t _vlib_config_function_\g<name>",
+    ),
+    (
+        re.compile(
+            '(?P<m>VLIB_EARLY_CONFIG_FUNCTION)\s*[(](?P<name>[a-zA-Z0-9_]+),\s*(?P<n>"[^"]+")(,[^)]*)?[)]'
+        ),
+        r"/** @brief (@em constructor) \g<m> (\g<name>, \g<n>) */ vlib_config_function_runtime_t _vlib_config_function_\g<name>",
+    ),
     # Search for "format_thing" and "unformat_thing" when used as a function pointer and add parens
-    ( re.compile("(?P<pre>(^|,)\s*)(?P<name>(un)?format_[a-zA-Z0-9_]+)(?P<post>\s*(,|$))"),
-        r"\g<pre>\g<name>()\g<post>" ),
-
+    (
+        re.compile(
+            "(?P<pre>(^|,)\s*)(?P<name>(un)?format_[a-zA-Z0-9_]+)(?P<post>\s*(,|$))"
+        ),
+        r"\g<pre>\g<name>()\g<post>",
+    ),
     # Search for CLIB_PAD_FROM_TO(...); and replace with padding
     # #define CLIB_PAD_FROM_TO(from,to) u8 pad_##from[(to) - (from)]
-    ( re.compile("(?P<m>CLIB_PAD_FROM_TO)\s*[(](?P<from>[^,]+),\s*(?P<to>[^)]+)[)]"),
-        r"/** Padding. */ u8 pad_\g<from>[(\g<to>) - (\g<from>)]" ),
-
+    (
+        re.compile("(?P<m>CLIB_PAD_FROM_TO)\s*[(](?P<from>[^,]+),\s*(?P<to>[^)]+)[)]"),
+        r"/** Padding. */ u8 pad_\g<from>[(\g<to>) - (\g<from>)]",
+    ),
 ]
 
 
 filename = sys.argv[1]
 cwd = os.getcwd()
-if filename[0:len(cwd)] == cwd:
-    filename = filename[len(cwd):]
+if filename[0 : len(cwd)] == cwd:
+    filename = filename[len(cwd) :]
     if filename[0] == "/":
         filename = filename[1:]
 
@@ -76,12 +107,12 @@
 
     for line in fd:
         line_num += 1
-        str = line[:-1] # filter \n
+        str = line[:-1]  # filter \n
 
         # Look for search/replace patterns
         for p in replace_patterns:
             str = p[0].sub(p[1], str)
 
-        sys.stdout.write(str+"\n")
+        sys.stdout.write(str + "\n")
 
 # All done
diff --git a/docs/_scripts/filter_h.py b/docs/_scripts/filter_h.py
index 0891fa7..31c4c51 100755
--- a/docs/_scripts/filter_h.py
+++ b/docs/_scripts/filter_h.py
@@ -26,17 +26,19 @@
 replace_patterns = [
     # Search for CLIB_PAD_FROM_TO(...); and replace with padding
     # #define CLIB_PAD_FROM_TO(from,to) u8 pad_##from[(to) - (from)]
-    (re.compile(r"(?P<m>CLIB_PAD_FROM_TO)\s*[(](?P<from>[^,]+),"
-                r"\s*(?P<to>[^)]+)[)]"),
-     r"/** Padding. */ u8 pad_\g<from>[(\g<to>) - (\g<from>)]"),
-
+    (
+        re.compile(
+            r"(?P<m>CLIB_PAD_FROM_TO)\s*[(](?P<from>[^,]+)," r"\s*(?P<to>[^)]+)[)]"
+        ),
+        r"/** Padding. */ u8 pad_\g<from>[(\g<to>) - (\g<from>)]",
+    ),
 ]
 
 
 filename = sys.argv[1]
 cwd = os.getcwd()
-if filename[0:len(cwd)] == cwd:
-    filename = filename[len(cwd):]
+if filename[0 : len(cwd)] == cwd:
+    filename = filename[len(cwd) :]
     if filename[0] == "/":
         filename = filename[1:]
 
@@ -51,6 +53,6 @@
         for p in replace_patterns:
             str = p[0].sub(p[1], str)
 
-        sys.stdout.write(str+"\n")
+        sys.stdout.write(str + "\n")
 
 # All done
diff --git a/docs/_scripts/includes_renderer.py b/docs/_scripts/includes_renderer.py
index 6bd501d..a2d422b 100644
--- a/docs/_scripts/includes_renderer.py
+++ b/docs/_scripts/includes_renderer.py
@@ -33,15 +33,14 @@
 
 
 class PluginRenderer(ContentRenderer):
-
     def _render_entry(self, output_file, entry):
         description = "<no-description-found>"
         # we use glob because a plugin can (ioam for now)
         # define the plugin definition in
         # a further subdirectory.
-        path = os.path.join(self.plugin_dir(), entry.name, '**')
+        path = os.path.join(self.plugin_dir(), entry.name, "**")
         for f in glob.iglob(path, recursive=True):
-            if not f.endswith('.c'):
+            if not f.endswith(".c"):
                 continue
             with open(f, "r", encoding="utf-8") as src:
                 for match in self.regex.finditer(src.read()):
@@ -56,7 +55,7 @@
         with open(fname, "w") as output_file:
             with os.scandir(self.plugin_dir()) as pdir:
                 for entry in sorted(pdir, key=lambda entry: entry.name):
-                    if not entry.name.startswith('.') and entry.is_dir():
+                    if not entry.name.startswith(".") and entry.is_dir():
                         self._render_entry(output_file, entry)
 
 
diff --git a/docs/_scripts/siphon/generate.py b/docs/_scripts/siphon/generate.py
index 2ae5a1b..1244c46 100644
--- a/docs/_scripts/siphon/generate.py
+++ b/docs/_scripts/siphon/generate.py
@@ -24,8 +24,10 @@
    themselves on this list."""
 siphon_patterns = []
 
+
 class Generate(object):
     """Matches a siphon comment block start"""
+
     siphon_block_start = re.compile("^\s*/\*\?\s*(.*)$")
 
     """Matches a siphon comment block stop"""
@@ -36,8 +38,10 @@
 
     """Matches a siphon block directive such as
        '%clicmd:group_label Debug CLI%'"""
-    siphon_block_directive = re.compile("(%s)\s*([a-zA-Z0-9_:]+)\s+(.*)\s*(%s)" % \
-            (siphon_block_delimiter, siphon_block_delimiter))
+    siphon_block_directive = re.compile(
+        "(%s)\s*([a-zA-Z0-9_:]+)\s+(.*)\s*(%s)"
+        % (siphon_block_delimiter, siphon_block_delimiter)
+    )
 
     """Matches the start of an initializer block"""
     siphon_initializer = re.compile("\s*=")
@@ -54,7 +58,6 @@
     """Logging handler"""
     log = None
 
-
     def __init__(self, output_directory, input_prefix):
         super(Generate, self).__init__()
         self.log = logging.getLogger("siphon.generate")
@@ -70,14 +73,13 @@
         self.output = {}
         for siphon in self.known_siphons:
             self.output[siphon] = {
-                    "file": "%s/%s.siphon" % (output_directory, siphon),
-                    "global": {},
-                    "items": [],
-                }
+                "file": "%s/%s.siphon" % (output_directory, siphon),
+                "global": {},
+                "items": [],
+            }
 
         self.input_prefix = input_prefix
 
-
     """
     count open and close braces in str
     return (0, index) when braces were found and count becomes 0.
@@ -87,16 +89,17 @@
     return (count, -1) if not all opening braces are closed, count is the
     current depth
     """
+
     def count_braces(self, str, count=0, found=False):
         for index in range(0, len(str)):
-            if str[index] == '{':
-                count += 1;
+            if str[index] == "{":
+                count += 1
                 found = True
-            elif str[index] == '}':
+            elif str[index] == "}":
                 if count == 0:
                     # means we never found an open brace
                     return (-1, -1)
-                count -= 1;
+                count -= 1
 
             if count == 0 and found:
                 return (count, index)
@@ -106,8 +109,8 @@
     def parse(self, filename):
         # Strip the current directory off the start of the
         # filename for brevity
-        if filename[0:len(self.input_prefix)] == self.input_prefix:
-            filename = filename[len(self.input_prefix):]
+        if filename[0 : len(self.input_prefix)] == self.input_prefix:
+            filename = filename[len(self.input_prefix) :]
             if filename[0] == "/":
                 filename = filename[1:]
 
@@ -115,8 +118,8 @@
         directory = os.path.dirname(filename)
         if directory[0:2] == "./":
             directory = directory[2:]
-        elif directory[0:len(self.input_prefix)] == self.input_prefix:
-            directory = directory[len(self.input_prefix):]
+        elif directory[0 : len(self.input_prefix)] == self.input_prefix:
+            directory = directory[len(self.input_prefix) :]
         if directory[0] == "/":
             directory = directory[1:]
 
@@ -133,9 +136,10 @@
 
             for line in fd:
                 line_num += 1
-                str = line[:-1] # filter \n
+                str = line[:-1]  # filter \n
 
                 """See if there is a block directive and if so extract it"""
+
                 def process_block_directive(str, directives):
                     m = self.siphon_block_directive.search(str)
                     if m is not None:
@@ -143,7 +147,7 @@
                         v = m.group(3).strip()
                         directives[k] = v
                         # Return only the parts we did not match
-                        return str[0:m.start(1)] + str[m.end(4):]
+                        return str[0 : m.start(1)] + str[m.end(4) :]
 
                     return str
 
@@ -200,27 +204,25 @@
                     # Skip to next line
                     continue
 
-
                 if siphon is None:
                     # Look for blocks we need to siphon
                     for p in siphon_patterns:
                         if p[0].match(str):
-                            siphon = [ p[1], str + "\n", 0 ]
+                            siphon = [p[1], str + "\n", 0]
                             siphon_line = line_num
 
                             # see if we have an initializer
                             m = self.siphon_initializer.search(str)
                             if m is not None:
                                 # count the braces on this line
-                                (count, index) = \
-                                    self.count_braces(str[m.start():])
+                                (count, index) = self.count_braces(str[m.start() :])
                                 siphon[2] = count
                                 # TODO - it's possible we have the
                                 # initializer all on the first line
                                 # we should check for it, but also
                                 # account for the possibility that
                                 # the open brace is on the next line
-                                #if count == 0:
+                                # if count == 0:
                                 #    # braces balanced
                                 #    close_siphon = siphon
                                 #    siphon = None
@@ -231,12 +233,11 @@
                 else:
                     # See if we should end the siphon here - do we have
                     # balanced braces?
-                    (count, index) = self.count_braces(str,
-                            count=siphon[2], found=True)
+                    (count, index) = self.count_braces(str, count=siphon[2], found=True)
                     if count == 0:
                         # braces balanced - add the substring and
                         # close the siphon
-                        siphon[1] += str[:index+1] + ";\n"
+                        siphon[1] += str[: index + 1] + ";\n"
                         close_siphon = siphon
                         siphon = None
                     else:
@@ -259,15 +260,15 @@
                             details[key] = directives[key]
 
                     # Copy details for this block
-                    details['file'] = filename
-                    details['directory'] = directory
-                    details['line_start'] = siphon_line
-                    details['line_end'] = line_num
-                    details['siphon_block'] = siphon_block.strip()
+                    details["file"] = filename
+                    details["directory"] = directory
+                    details["line_start"] = siphon_line
+                    details["line_end"] = line_num
+                    details["siphon_block"] = siphon_block.strip()
                     details["block"] = close_siphon[1]
 
                     # Store the item
-                    self.output[siphon_name]['items'].append(details)
+                    self.output[siphon_name]["items"].append(details)
 
                     # All done
                     close_siphon = None
@@ -275,7 +276,7 @@
 
             # Update globals
             for key in directives.keys():
-                if ':' not in key:
+                if ":" not in key:
                     continue
 
                 if filename.endswith("/dir.dox"):
@@ -288,19 +289,17 @@
 
                 if sn not in self.output:
                     self.output[sn] = {}
-                if 'global' not in self.output[sn]:
-                    self.output[sn]['global'] = {}
-                if l not in self.output[sn]['global']:
-                    self.output[sn]['global'][l] = {}
+                if "global" not in self.output[sn]:
+                    self.output[sn]["global"] = {}
+                if l not in self.output[sn]["global"]:
+                    self.output[sn]["global"][l] = {}
 
-                self.output[sn]['global'][l][label] = directives[key]
+                self.output[sn]["global"][l][label] = directives[key]
 
     def deliver(self):
         # Write out the data
         for siphon in self.output.keys():
             self.log.info("Saving siphon data %s." % siphon)
             s = self.output[siphon]
-            with open(s['file'], "a") as fp:
-                json.dump(s, fp,
-                    separators=(',', ': '), indent=4, sort_keys=True)
-
+            with open(s["file"], "a") as fp:
+                json.dump(s, fp, separators=(",", ": "), indent=4, sort_keys=True)
diff --git a/docs/_scripts/siphon/generate_clicmd.py b/docs/_scripts/siphon/generate_clicmd.py
index 6d24aaf..2e2f628 100644
--- a/docs/_scripts/siphon/generate_clicmd.py
+++ b/docs/_scripts/siphon/generate_clicmd.py
@@ -17,8 +17,11 @@
 from . import generate
 
 # Register our regexp
-generate.siphon_patterns.append((
-    re.compile("(?P<m>VLIB_CLI_COMMAND)\s*"
-        "[(](?P<name>[a-zA-Z0-9_]+)(,[^)]*)?[)]"),
-    "clicmd"
-))
+generate.siphon_patterns.append(
+    (
+        re.compile(
+            "(?P<m>VLIB_CLI_COMMAND)\s*" "[(](?P<name>[a-zA-Z0-9_]+)(,[^)]*)?[)]"
+        ),
+        "clicmd",
+    )
+)
diff --git a/docs/_scripts/siphon/generate_syscfg.py b/docs/_scripts/siphon/generate_syscfg.py
index 52c802e..105a59c 100644
--- a/docs/_scripts/siphon/generate_syscfg.py
+++ b/docs/_scripts/siphon/generate_syscfg.py
@@ -17,8 +17,12 @@
 from . import generate
 
 # Register our regexp
-generate.siphon_patterns.append((
-    re.compile("(?P<m>VLIB_CONFIG_FUNCTION)\s*"
-        '[(](?P<fn>[a-zA-Z0-9_]+)\s*,\s*"(?P<name>[^"]*)"[)]'),
-    "syscfg"
-))
+generate.siphon_patterns.append(
+    (
+        re.compile(
+            "(?P<m>VLIB_CONFIG_FUNCTION)\s*"
+            '[(](?P<fn>[a-zA-Z0-9_]+)\s*,\s*"(?P<name>[^"]*)"[)]'
+        ),
+        "syscfg",
+    )
+)
diff --git a/docs/_scripts/siphon/parsers.py b/docs/_scripts/siphon/parsers.py
index 162205d..1a7d1f5 100644
--- a/docs/_scripts/siphon/parsers.py
+++ b/docs/_scripts/siphon/parsers.py
@@ -18,9 +18,10 @@
 intNum = pp.Word(pp.nums)
 hexNum = pp.Literal("0x") + pp.Word(pp.hexnums)
 octalNum = pp.Literal("0") + pp.Word("01234567")
-integer = (hexNum | octalNum | intNum) + \
-    pp.Optional(pp.Literal("ULL") | pp.Literal("LL") | pp.Literal("L"))
-floatNum = pp.Regex(r'\d+(\.\d*)?([eE]\d+)?') + pp.Optional(pp.Literal("f"))
+integer = (hexNum | octalNum | intNum) + pp.Optional(
+    pp.Literal("ULL") | pp.Literal("LL") | pp.Literal("L")
+)
+floatNum = pp.Regex(r"\d+(\.\d*)?([eE]\d+)?") + pp.Optional(pp.Literal("f"))
 char = pp.Literal("'") + pp.Word(pp.printables, exact=1) + pp.Literal("'")
 arrayIndex = integer | ident
 
@@ -36,23 +37,29 @@
 # initializer := { [member = ] (variable | expression | { initializer } ) }
 typeName = ident
 varName = ident
-typeSpec = pp.Optional("unsigned") + \
-           pp.oneOf("int long short float double char u8 i8 void") + \
-           pp.Optional(pp.Word("*"), default="")
-typeCast = pp.Combine( "(" + ( typeSpec | typeName ) + ")" ).suppress()
+typeSpec = (
+    pp.Optional("unsigned")
+    + pp.oneOf("int long short float double char u8 i8 void")
+    + pp.Optional(pp.Word("*"), default="")
+)
+typeCast = pp.Combine("(" + (typeSpec | typeName) + ")").suppress()
 
-string = pp.Combine(pp.OneOrMore(pp.QuotedString(quoteChar='"',
-    escChar='\\', multiline=True)), adjacent=False)
+string = pp.Combine(
+    pp.OneOrMore(pp.QuotedString(quoteChar='"', escChar="\\", multiline=True)),
+    adjacent=False,
+)
 literal = pp.Optional(typeCast) + (integer | floatNum | char | string)
-var = pp.Combine(pp.Optional(typeCast) + varName +
-    pp.Optional("[" + arrayIndex + "]"))
+var = pp.Combine(pp.Optional(typeCast) + varName + pp.Optional("[" + arrayIndex + "]"))
 
 # This could be more complete, but suffices for our uses
-expr = (literal | var)
+expr = literal | var
 
 """Parse and render a block of text into a Python dictionary."""
+
+
 class Parser(object):
     """Compiled PyParsing BNF"""
+
     _parser = None
 
     def __init__(self):
@@ -71,6 +78,8 @@
 
 
 """Parser for function-like macros - without the closing semi-colon."""
+
+
 class ParserFunctionMacro(Parser):
     def BNF(self):
         # VLIB_CONFIG_FUNCTION (unix_config, "unix")
@@ -91,6 +100,8 @@
 
 
 """Parser for function-like macros with a closing semi-colon."""
+
+
 class ParseFunctionMacroStmt(ParserFunctionMacro):
     def BNF(self):
         # VLIB_CONFIG_FUNCTION (unix_config, "unix");
@@ -106,6 +117,8 @@
 function-like macro, equals sign, and then a normal C struct initializer
 block.
 """
+
+
 class MacroInitializer(ParserFunctionMacro):
     def BNF(self):
         # VLIB_CLI_COMMAND (show_sr_tunnel_command, static) = {
@@ -115,14 +128,15 @@
         # };
         cs = pp.Forward()
 
-
-        member = pp.Combine(dot + varName + pp.Optional("[" + arrayIndex + "]"),
-            adjacent=False)
-        value = (expr | cs)
+        member = pp.Combine(
+            dot + varName + pp.Optional("[" + arrayIndex + "]"), adjacent=False
+        )
+        value = expr | cs
 
         entry = pp.Group(pp.Optional(member + equals, default="") + value)
-        entries = (pp.ZeroOrMore(entry + comma) + entry + pp.Optional(comma)) | \
-                  (pp.ZeroOrMore(entry + comma))
+        entries = (pp.ZeroOrMore(entry + comma) + entry + pp.Optional(comma)) | (
+            pp.ZeroOrMore(entry + comma)
+        )
 
         cs << (lbrace + entries + rbrace)
 
diff --git a/docs/_scripts/siphon/process.py b/docs/_scripts/siphon/process.py
index e3a7015..341b7cb 100644
--- a/docs/_scripts/siphon/process.py
+++ b/docs/_scripts/siphon/process.py
@@ -88,7 +88,8 @@
             loader=loader,
             trim_blocks=True,
             autoescape=False,
-            keep_trailing_newline=True)
+            keep_trailing_newline=True,
+        )
 
         # Convenience, get a reference to the internal escape and
         # unescape methods in html.parser. These then become
@@ -103,32 +104,38 @@
     # Output renderers
 
     """Returns an object to be used as the sorting key in the item index."""
+
     def index_sort_key(self, group):
         return group
 
     """Returns a string to use as the header at the top of the item index."""
+
     def index_header(self):
         return self.template("index_header")
 
     """Returns the string fragment to use for each section in the item
     index."""
+
     def index_section(self, group):
         return self.template("index_section", group=group)
 
     """Returns the string fragment to use for each entry in the item index."""
+
     def index_entry(self, meta, item):
         return self.template("index_entry", meta=meta, item=item)
 
     """Returns an object, typically a string, to be used as the sorting key
     for items within a section."""
+
     def item_sort_key(self, item):
-        return item['name']
+        return item["name"]
 
     """Returns a key for grouping items together."""
-    def group_key(self, directory, file, macro, name):
-        _global = self._cmds['_global']
 
-        if file in _global and 'group_label' in _global[file]:
+    def group_key(self, directory, file, macro, name):
+        _global = self._cmds["_global"]
+
+        if file in _global and "group_label" in _global[file]:
             self._group[file] = (directory, file)
             return file
 
@@ -136,60 +143,59 @@
         return directory
 
     """Returns a key for identifying items within a grouping."""
+
     def item_key(self, directory, file, macro, name):
         return name
 
     """Returns a string to use as the header when rendering the item."""
+
     def item_header(self, group):
         return self.template("item_header", group=group)
 
     """Returns a string to use as the body when rendering the item."""
+
     def item_format(self, meta, item):
         return self.template("item_format", meta=meta, item=item)
 
     """Returns a string to use as the label for the page reference."""
+
     def page_label(self, group):
-        return "_".join((
-            self.name,
-            self.sanitize_label(group)
-        ))
+        return "_".join((self.name, self.sanitize_label(group)))
 
     """Returns a title to use for a page."""
+
     def page_title(self, group):
-        _global = self._cmds['_global']
+        _global = self._cmds["_global"]
         (directory, file) = self._group[group]
 
-        if file and file in _global and 'group_label' in _global[file]:
-            return _global[file]['group_label']
+        if file and file in _global and "group_label" in _global[file]:
+            return _global[file]["group_label"]
 
-        if directory in _global and 'group_label' in _global[directory]:
-            return _global[directory]['group_label']
+        if directory in _global and "group_label" in _global[directory]:
+            return _global[directory]["group_label"]
 
         return directory
 
     """Returns a string to use as the label for the section reference."""
+
     def item_label(self, group, item):
-        return "__".join((
-            self.name,
-            item
-        ))
+        return "__".join((self.name, item))
 
     """Label sanitizer; for creating Doxygen references"""
+
     def sanitize_label(self, value):
-        return value.replace(" ", "_") \
-                    .replace("/", "_") \
-                    .replace(".", "_")
+        return value.replace(" ", "_").replace("/", "_").replace(".", "_")
 
     """Template processor"""
+
     def template(self, name, **kwargs):
         tpl = self._tplenv.get_template(name + self._format.extension)
-        return tpl.render(
-            this=self,
-            **kwargs)
+        return tpl.render(this=self, **kwargs)
 
     # Processing methods
 
     """Parse the input file into a more usable dictionary structure."""
+
     def load_json(self, files):
         self._cmds = {}
         self._group = {}
@@ -198,34 +204,37 @@
         line_start = 0
         for filename in files:
             filename = os.path.relpath(filename)
-            self.log.info("Parsing items in file \"%s\"." % filename)
+            self.log.info('Parsing items in file "%s".' % filename)
             data = None
             with open(filename, "r") as fd:
                 data = json.load(fd)
 
-            self._cmds['_global'] = data['global']
+            self._cmds["_global"] = data["global"]
 
             # iterate the items loaded and regroup it
             for item in data["items"]:
                 try:
-                    o = self._parser.parse(item['block'])
+                    o = self._parser.parse(item["block"])
                 except Exception:
-                    self.log.error("Exception parsing item: %s\n%s"
-                                   % (json.dumps(item, separators=(',', ': '),
-                                                 indent=4),
-                                      item['block']))
+                    self.log.error(
+                        "Exception parsing item: %s\n%s"
+                        % (
+                            json.dumps(item, separators=(",", ": "), indent=4),
+                            item["block"],
+                        )
+                    )
                     raise
 
                 # Augment the item with metadata
                 o["meta"] = {}
                 for key in item:
-                    if key == 'block':
+                    if key == "block":
                         continue
-                    o['meta'][key] = item[key]
+                    o["meta"][key] = item[key]
 
                 # Load some interesting fields
-                directory = item['directory']
-                file = item['file']
+                directory = item["directory"]
+                file = item["file"]
                 macro = o["macro"]
                 name = o["name"]
 
@@ -240,6 +249,7 @@
 
     """Iterate over the input data, calling render methods to generate the
     output."""
+
     def process(self, out=None):
 
         if out is None:
@@ -257,11 +267,12 @@
 
         # Iterate the dictionary and process it
         for group in sorted(self._cmds.keys(), key=group_sort_key):
-            if group.startswith('_'):
+            if group.startswith("_"):
                 continue
 
-            self.log.info("Processing items in group \"%s\" (%s)." %
-                          (group, group_sort_key(group)))
+            self.log.info(
+                'Processing items in group "%s" (%s).' % (group, group_sort_key(group))
+            )
 
             # Generate the section index entry (write it now)
             out.write(self.index_section(group))
@@ -273,15 +284,16 @@
                 return self.item_sort_key(self._cmds[group][key])
 
             for key in sorted(self._cmds[group].keys(), key=item_sort_key):
-                self.log.debug("--- Processing key \"%s\" (%s)." %
-                               (key, item_sort_key(key)))
+                self.log.debug(
+                    '--- Processing key "%s" (%s).' % (key, item_sort_key(key))
+                )
 
                 o = self._cmds[group][key]
                 meta = {
-                    "directory": o['meta']['directory'],
-                    "file": o['meta']['file'],
-                    "macro": o['macro'],
-                    "name": o['name'],
+                    "directory": o["meta"]["directory"],
+                    "file": o["meta"]["file"],
+                    "macro": o["macro"],
+                    "name": o["name"],
                     "key": key,
                     "label": self.item_label(group, key),
                 }
@@ -304,7 +316,7 @@
 
     def do_cliexstart(self, matchobj):
         title = matchobj.group(1)
-        title = ' '.join(title.splitlines())
+        title = " ".join(title.splitlines())
         content = matchobj.group(2)
         content = re.sub(r"\n", r"\n    ", content)
         return "\n\n.. code-block:: console\n\n    %s\n    %s\n\n" % (title, content)
@@ -316,7 +328,7 @@
 
     def do_cliexcmd(self, matchobj):
         content = matchobj.group(1)
-        content = ' '.join(content.splitlines())
+        content = " ".join(content.splitlines())
         return "\n\n.. code-block:: console\n\n    %s\n\n" % content
 
     def process_list(self, matchobj):
@@ -351,7 +363,9 @@
         s = re.sub(r"@TODO[^\n]*", "", s)
         # ----------- code blocks
         s = re.sub(r"@cliexcmd{(.+?)}", self.do_cliexcmd, s, flags=re.DOTALL)
-        s = re.sub(r"@cliexstart{(.+?)}(.+?)@cliexend", self.do_cliexstart, s, flags=re.DOTALL)
+        s = re.sub(
+            r"@cliexstart{(.+?)}(.+?)@cliexend", self.do_cliexstart, s, flags=re.DOTALL
+        )
         s = re.sub(r"@clistart(.+?)@cliend", self.do_clistart, s, flags=re.DOTALL)
         # ----------- lists
         s = re.sub(r"^\s*-", r"\n@@@@", s, flags=re.MULTILINE)
@@ -377,6 +391,7 @@
         s = re.sub(r"\n[ \f\v\t]*", "\n", s)
         return s
 
+
 class Format(object):
     """Output format class"""
 
@@ -389,6 +404,7 @@
 
 class FormatMarkdown(Format):
     """Markdown output format"""
+
     name = "markdown"
     extension = ".md"
 
@@ -399,6 +415,7 @@
 
 class FormatItemlist(Format):
     """Itemlist output format"""
+
     name = "itemlist"
     extension = ".itemlist"
 
diff --git a/docs/_scripts/siphon/process_clicmd.py b/docs/_scripts/siphon/process_clicmd.py
index bf27051..afc24ae 100644
--- a/docs/_scripts/siphon/process_clicmd.py
+++ b/docs/_scripts/siphon/process_clicmd.py
@@ -17,6 +17,7 @@
 from . import process, parsers
 import os
 
+
 class SiphonCLICMD(process.Siphon):
 
     name = "clicmd"
@@ -32,37 +33,36 @@
         return self.page_label(group) + ".rst"
 
     def index_sort_key(self, group):
-        _global = self._cmds['_global']
+        _global = self._cmds["_global"]
         if group not in self._group:
             return group
         (directory, file) = self._group[group]
 
-        if file in _global and 'group_label' in _global[file]:
-            return _global[file]['group_label']
+        if file in _global and "group_label" in _global[file]:
+            return _global[file]["group_label"]
 
-        if directory in _global and 'group_label' in _global[directory]:
-            return _global[directory]['group_label']
+        if directory in _global and "group_label" in _global[directory]:
+            return _global[directory]["group_label"]
 
         return group
 
     def item_sort_key(self, item):
-        return item['value']['path']
+        return item["value"]["path"]
 
     def item_label(self, group, item):
-        return "_".join((
-            self.name,
-            self.sanitize_label(self._cmds[group][item]['value']['path'])
-        ))
+        return "_".join(
+            (self.name, self.sanitize_label(self._cmds[group][item]["value"]["path"]))
+        )
 
     def page_title(self, group):
-        _global = self._cmds['_global']
+        _global = self._cmds["_global"]
         (directory, file) = self._group[group]
 
-        if file and file in _global and 'group_label' in _global[file]:
-            return _global[file]['group_label']
+        if file and file in _global and "group_label" in _global[file]:
+            return _global[file]["group_label"]
 
-        if directory in _global and 'group_label' in _global[directory]:
-            return _global[directory]['group_label']
+        if directory in _global and "group_label" in _global[directory]:
+            return _global[directory]["group_label"]
 
         file_ext = os.path.basename(directory)
         fname, ext = os.path.splitext(file_ext)
diff --git a/docs/conf.py b/docs/conf.py
index 26ccb3f..550eee8 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -20,14 +20,16 @@
 
 # -- Project information -----------------------------------------------------
 
-project = u'The Vector Packet Processor'
-copyright = u'2018-2022, Linux Foundation'
-author = u'FD.io VPP Community'
+project = "The Vector Packet Processor"
+copyright = "2018-2022, Linux Foundation"
+author = "FD.io VPP Community"
 
 # The short X.Y version
 version = subprocess.run(["git", "describe"], stdout=subprocess.PIPE, text=True).stdout
 # The full version, including alpha/beta/rc tags
-release = subprocess.run(["git", "describe", "--long"], stdout=subprocess.PIPE, text=True).stdout
+release = subprocess.run(
+    ["git", "describe", "--long"], stdout=subprocess.PIPE, text=True
+).stdout
 
 
 # -- General configuration ---------------------------------------------------
@@ -40,29 +42,27 @@
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
 extensions = [
-    'sphinx.ext.autodoc',
-    'sphinx.ext.viewcode',
-    'recommonmark',
-    'sphinxcontrib.spelling']
+    "sphinx.ext.autodoc",
+    "sphinx.ext.viewcode",
+    "recommonmark",
+    "sphinxcontrib.spelling",
+]
 
-spelling_word_list_filename = 'spelling_wordlist.txt'
+spelling_word_list_filename = "spelling_wordlist.txt"
 
 # do not spell check those files
-spelling_exclude_patterns = ['aboutvpp/releasenotes/*']
+spelling_exclude_patterns = ["aboutvpp/releasenotes/*"]
 
 # Add any paths that contain templates here, relative to this directory.
-templates_path = ['_templates']
+templates_path = ["_templates"]
 
 # The suffix(es) of source filenames.
 # You can specify multiple suffix as a list of string:
 #
-source_suffix = {
-    '.rst': 'restructuredtext',
-    '.md': 'markdown'
-}
+source_suffix = {".rst": "restructuredtext", ".md": "markdown"}
 
 # The master toctree document.
-master_doc = 'index'
+master_doc = "index"
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
@@ -74,10 +74,10 @@
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.
 # This pattern also affects html_static_path and html_extra_path .
-exclude_patterns = ['Thumbs.db', '.DS_Store', '_scripts', 'venv', '_generated']
+exclude_patterns = ["Thumbs.db", ".DS_Store", "_scripts", "venv", "_generated"]
 
 # The name of the Pygments (syntax highlighting) style to use.
-pygments_style = 'default'
+pygments_style = "default"
 
 
 # -- Options for HTML output -------------------------------------------------
@@ -88,15 +88,17 @@
 
 # import sphinx_theme
 
-templates_path = ['_templates']
+templates_path = ["_templates"]
 
 html_theme = "sphinx_rtd_theme"
 
-html_theme_path = ["_themes", ]
+html_theme_path = [
+    "_themes",
+]
 
 # The name of an image file (relative to this directory) to place at the top
 # of the sidebar.
-html_logo = '_static/fd-io_red_white.png'
+html_logo = "_static/fd-io_red_white.png"
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
@@ -107,11 +109,12 @@
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-html_static_path = ['_static']
+html_static_path = ["_static"]
 
 
 def setup(app):
-    app.add_css_file('css/rules.css')
+    app.add_css_file("css/rules.css")
+
 
 # Custom sidebar templates, must be a dictionary that maps document names
 # to template names.
@@ -127,7 +130,7 @@
 # -- Options for HTMLHelp output ---------------------------------------------
 
 # Output file base name for HTML help builder.
-htmlhelp_basename = 'Vector Packet Processor'
+htmlhelp_basename = "Vector Packet Processor"
 
 
 # -- Options for LaTeX output ------------------------------------------------
@@ -136,15 +139,12 @@
     # The paper size ('letterpaper' or 'a4paper').
     #
     # 'papersize': 'letterpaper',
-
     # The font size ('10pt', '11pt' or '12pt').
     #
     # 'pointsize': '10pt',
-
     # Additional stuff for the LaTeX preamble.
     #
     # 'preamble': '',
-
     # Latex figure (float) alignment
     #
     # 'figure_align': 'htbp',
@@ -154,9 +154,13 @@
 # (source start file, target name, title,
 #  author, documentclass [howto, manual, or own class]).
 latex_documents = [
-    (master_doc, 'Vector Packet Processor.tex',
-     u'Vector Packet Processor Documentation',
-     u'John DeNisco', 'manual'),
+    (
+        master_doc,
+        "Vector Packet Processor.tex",
+        "Vector Packet Processor Documentation",
+        "John DeNisco",
+        "manual",
+    ),
 ]
 
 
@@ -165,9 +169,13 @@
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
 man_pages = [
-    (master_doc, 'Vector Packet Processor',
-     u'Vector Packet Processor Documentation',
-     [author], 1)
+    (
+        master_doc,
+        "Vector Packet Processor",
+        "Vector Packet Processor Documentation",
+        [author],
+        1,
+    )
 ]
 
 
@@ -177,10 +185,15 @@
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
-    (master_doc, 'Vector Packet Processor',
-     u'Vector Packet Processor Documentation',
-     author, 'Vector Packet Processor', 'One line description of project.',
-     'Miscellaneous'),
+    (
+        master_doc,
+        "Vector Packet Processor",
+        "Vector Packet Processor Documentation",
+        author,
+        "Vector Packet Processor",
+        "One line description of project.",
+        "Miscellaneous",
+    ),
 ]