Merge ~xavpaice/charm-telegraf:lint-20.08 into charm-telegraf:master

[Xav Paice]

Extra Linting completed for 20.08 charm release

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

This merge proposal is being monitored by mergebot. Change the status to Approved to merge.

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

Unable to determine commit message from repository - please click "Set commit message" and enter the commit message manually.

[James Troup (elmo)]

LGTM

review: Approve

[Alvaro Uria (aluria)]

+1 to this and the other 2 related MPs (makefile and blacken)

review: Approve

[🤖 Canonical IS Merge Bot (canonical-is-mergebot)]

Change successfully merged at revision 5b7391d840a618ab91dc1597864bb29138a04d19

diff --git a/src/files/telegraf_exec_metrics.py b/src/files/telegraf_exec_metrics.py
index f03e23a..d9b3402 100755
--- a/src/files/telegraf_exec_metrics.py
+++ b/src/files/telegraf_exec_metrics.py
@@ -1,29 +1,32 @@
 #!/usr/bin/env python3
-import os
-import re
-import sys
+import argparse
 import json
 import logging
-import argparse
-import subprocess
+import os
+import re
 import shutil
+import subprocess
+import sys
 from collections import OrderedDict
 from textwrap import dedent
 
-from insights.tests import context_wrap
 from insights.parsers.softnet_stat import SoftNetStats
-
+from insights.tests import context_wrap
 
 LOG = logging.getLogger()
 
 METRICS = OrderedDict()
 
 
-def register_metric(MetricClass):
-    """A decorator to create a metric class instance and register it"""
-    metric = MetricClass()
+def register_metric(metricclass):
+    """Create metric class instance.
+
+    Decorator that creates a metric class and registers it.
+    """
+    metric = metricclass()
     METRICS[metric.name] = metric
-    return MetricClass
+
+    return metricclass
 
 
 class FileMetric:
@@ -46,18 +49,22 @@ class FileMetric:
         LOG.info("rendering config to %s", config_path)
         script = os.path.abspath(__file__)
         output = self.config_template.format(
-            python=python or sys.executable, script=script, name=self.name,
+            python=python or sys.executable, script=script, name=self.name
         )
         LOG.debug(output)
+
         if not dry_run:
             with open(config_path, mode="w", encoding="utf8") as f:
                 f.write(output)
+
         return output
 
     def remove_config(self, configs_dir, dry_run=False):
         config_path = self.config_path(configs_dir)
+
         if os.path.isfile(config_path):
             LOG.info("removing %s", config_path)
+
             if not dry_run:
                 os.remove(config_path)
         else:
@@ -78,6 +85,7 @@ class SockStatFileMetric(FileMetric):
 
     def parse(self, content):
         results = {}
+
         for line in content.splitlines():
             LOG.debug("parsing line: %s", line)
             # line example: TCP: inuse 62 orphan 0 tw 5 alloc 222 mem 20
@@ -86,9 +94,11 @@ class SockStatFileMetric(FileMetric):
             count = len(items)
             assert count % 2 == 0
             group = {}
+
             for i in range(0, count, 2):
                 group[items[i]] = int(items[i + 1])
             results[key.strip()] = group
+
         return results
 
 
@@ -175,18 +185,22 @@ class BuddyinfoFileMetric(FileMetric):
         re_line = re.compile(
             r"Node\s+(?P<node>\d+).*zone\s+(?P<zone>\w+)\s+(?P<pages>.*)"
         )
+
         for line in content.splitlines():
             LOG.debug(line)
             match = re_line.match(line)
+
             if match:
                 data = match.groupdict()
                 LOG.debug(data)
                 pages = data["pages"].split()
+
                 if not human_sizes:
                     human_sizes = [
                         self._get_human_size(page_size * 2 ** i)
                         for i, _ in enumerate(pages)
                     ]
+
                 for k, v in zip(human_sizes, pages):
                     items.append(
                         {
@@ -196,6 +210,7 @@ class BuddyinfoFileMetric(FileMetric):
                             "count": int(v),
                         }
                     )
+
         return items
 
 
@@ -228,14 +243,17 @@ class ZoneinfoFileMetric(FileMetric):
             re.MULTILINE + re.DOTALL,
         )
         items = []
+
         for match in pattern.finditer(content):
             data = match.groupdict()
             LOG.debug(data)
             # convert str to int
+
             for k, v in data.items():
                 if v.isdigit():
                     data[k] = int(v)
             items.append(data)
+
         return items
 
 
@@ -246,11 +264,14 @@ class CmdMetric(FileMetric):
     def get_cmd_output(self, cmd, is_json=False):
         LOG.debug("running cmd: %s", " ".join(cmd))
         output = subprocess.check_output(cmd).decode("utf8").strip()
+
         return json.loads(output) if is_json else output
 
     def get_input_content(self):
         if self.input_file:
-            # if provided, still read cmd output from a file, helpful for debuging/testing.
+            # if provided, still read cmd output from a file, helpful
+            # for debuging/testing.
+
             return super().get_input_content()
         else:
             return self.get_cmd_output(self.cmd)
@@ -277,17 +298,18 @@ class NetNSCmdMetric(CmdMetric):
         items = []
         # find openstack/neutron netns list pattern
         pattern = re.compile(r"^([\w-]+)\s+\(id:\s+(\d+)\)", flags=re.M)
+
         for match in pattern.finditer(content):
             items.append(
-                {"namespace": match.group(1), "id": match.group(2), "state": 1,}
+                {"namespace": match.group(1), "id": match.group(2), "state": 1}
             )
 
         # no re matches, should be in simple list format
+
         if not items:
             for line in content.splitlines():
-                items.append(
-                    {"namespace": line.strip(), "state": 1,}
-                )
+                items.append({"namespace": line.strip(), "state": 1})
+
         return items
 
 
@@ -321,8 +343,10 @@ class OvsDumpFlowsCmdMetric(CmdMetric):
         flows = {}
 
         ovs_cmd = "ovs-ofctl"
+
         if not shutil.which(ovs_cmd):
             LOG.error('openvswitch command "%s" is not available, exit', ovs_cmd)
+
             return flows
 
         for bridge in ["br-int", "br-tun", "br-data"]:
@@ -335,7 +359,6 @@ class OvsDumpFlowsCmdMetric(CmdMetric):
     def parse(self, input_content):
         """Parse input content for each bridge and convert to a json list.
 
-
         Example final json result:
 
         [
@@ -356,12 +379,14 @@ class OvsDumpFlowsCmdMetric(CmdMetric):
         # input_content here is a dict with cmd output for each bridge for this metric
         flows = input_content
         items = []
+
         for bridge, output in flows.items():
             # when invoked via python (or redirected) it includes an extra line
             # like 'NXST_FLOW reply (xid=0x4):'
             # so need to substract one
             lines = output.splitlines()
             items.append({"bridge": bridge, "count": len(lines) - 1})
+
         return items
 
 
@@ -381,8 +406,9 @@ class OvsDpCtlCmdMetric(CmdMetric):
     )
 
     def parse_fields(self, text):
-        """
-        parse lines following pattern to a dictionary,
+        """Parse lines following pattern to a dictionary.
+
+        Parse lines following pattern to a dictionary,
         converting int/floats as relevant
          'hit:706 missed:456 lost:0'
         """
@@ -396,23 +422,26 @@ class OvsDpCtlCmdMetric(CmdMetric):
             # parse lines of key/values into a dict
             # hit:706 missed:489 lost:1
             data = {}
+
             for datapair in text.split():
                 k, v = datapair.split(":")
                 # do nothing if the line has question marks (no data), e.g.:
                 # RX packets:0 errors:? dropped:? overruns:? frame:?
+
                 if "?" in v:
                     continue
                 # reuse field parsing logic by recursion, no nested dicts
                 data[k] = self.parse_fields(v)
+
             return data
+
         return text
 
     def parse(self, input_content):
-        """
-        parse the output of `ovs-appctl dpctl/show -s`
-        """
+        """Parse the output of `ovs-appctl dpctl/show -s`."""
         result = []
         datapath_entry = None
+
         for line in input_content.splitlines():
             if line[0].isalnum():  # datapath header, other lines start w/space or tab
                 if datapath_entry:  # store the current one before creating a new one
@@ -422,9 +451,10 @@ class OvsDpCtlCmdMetric(CmdMetric):
                     "port": "",
                     "portname": "",
                 }
+
                 continue
 
-            label, rest = (l.strip() for l in line.split(":", maxsplit=1))
+            label, rest = (item.strip() for item in line.split(":", maxsplit=1))
 
             if label.startswith("port"):
                 # complete previous entry, and initialise a new one for the new port
@@ -434,12 +464,14 @@ class OvsDpCtlCmdMetric(CmdMetric):
                 }
                 datapath_entry["port"] = label.split()[-1]
                 datapath_entry["portname"] = rest
+
                 continue
 
             if datapath_entry["port"]:  # parsing lines corresponding to a port block
                 if "X packets" in label:
                     # parse the RX|TX packets line using a prefix
                     prefix, data = line.strip().split(maxsplit=1)
+
                     for k, v in self.parse_fields(data).items():
                         datapath_entry["{}_{}".format(prefix, k)] = v
                 else:  # parse the non-packet lines (collisions/bytes)
@@ -449,12 +481,14 @@ class OvsDpCtlCmdMetric(CmdMetric):
                     # use RX/TX as a prefix by removing the space
                     data = line.replace(" bytes", "_bytes")
                     datapath_entry.update(self.parse_fields(data))
+
                 continue
 
             # all other cases, are datapairs or metrics
             datapath_entry[label] = self.parse_fields(rest.rstrip())
 
         # handle the end of the output
+
         if datapath_entry:
             result.append(datapath_entry)
 
@@ -462,17 +496,18 @@ class OvsDpCtlCmdMetric(CmdMetric):
 
 
 def render_config_files(configs_dir, python, disabled_metrics="", dry_run=False):
-    """Render config files for any metrics not disabled, and remove any disabled"""
-
+    """Render config files for any metrics not disabled, and remove any disabled."""
     disabled_metrics_set = (
         set(disabled_metrics.split(":")) if disabled_metrics else set([])
     )
+
     for metric in disabled_metrics_set:
         try:
             METRICS[metric].remove_config(configs_dir, dry_run=dry_run)
         except KeyError:
             LOG.warning("metric name %s not in %s", metric, ",".join(METRICS))
     enabled_metrics_set = set(METRICS.keys()) - disabled_metrics_set
+
     for metric in enabled_metrics_set:
         METRICS[metric].render_config(configs_dir, python, dry_run=dry_run)
 
@@ -484,10 +519,7 @@ def main():
     )
     choices = list(METRICS)  # sorted dict
     argparser.add_argument(
-        "--metric",
-        choices=choices,
-        default=choices[0],
-        help="which metric to execuate",
+        "--metric", choices=choices, default=choices[0], help="which metric to execuate"
     )
     argparser.add_argument(
         "-f",
@@ -499,7 +531,8 @@ def main():
         "--render-config-files",
         dest="render_config_files",
         action="store_true",
-        help="render config files for all metrics, use --disabled-metrics to exclude specific ones",
+        help="render config files for all metrics, use --disabled-metrics to "
+        "exclude specific ones",
     )
     argparser.add_argument(
         "--disabled-metrics",
@@ -511,7 +544,8 @@ def main():
         "--python",
         dest="python",
         default=sys.executable,
-        help="python interperter path in config file to execute this script, required for venv",
+        help="python interperter path in config file to execute this script, "
+        "required for venv",
     )
     # useful for testing
     argparser.add_argument(
@@ -521,10 +555,10 @@ def main():
         help="telegraf configs dir for exec metrics",
     )
     argparser.add_argument(
-        "--dry-run", action="store_true", help="dry run without real actions",
+        "--dry-run", action="store_true", help="dry run without real actions"
     )
     argparser.add_argument(
-        "-v", "--verbose", action="store_true", help="be verbose in log",
+        "-v", "--verbose", action="store_true", help="be verbose in log"
     )
 
     cli = argparser.parse_args()
@@ -542,6 +576,7 @@ def main():
         )
     else:
         metric = METRICS[cli.metric]
+
         if cli.input_file:
             metric.input_file = cli.input_file
         output = metric.parse(metric.get_input_content())
diff --git a/src/hooks/relations/apache-website/requires.py b/src/hooks/relations/apache-website/requires.py
index ecb663a..861fb8f 100644
--- a/src/hooks/relations/apache-website/requires.py
+++ b/src/hooks/relations/apache-website/requires.py
@@ -14,9 +14,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from charms.reactive import hook
-from charms.reactive import RelationBase
-from charms.reactive import scopes
+from charms.reactive import RelationBase, hook, scopes
 
 
 class WSGIRequires(RelationBase):
diff --git a/src/hooks/relations/statistics/requires.py b/src/hooks/relations/statistics/requires.py
index 4aafb2a..702db6f 100644
--- a/src/hooks/relations/statistics/requires.py
+++ b/src/hooks/relations/statistics/requires.py
@@ -14,9 +14,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from charms.reactive import hook
-from charms.reactive import RelationBase
-from charms.reactive import scopes
+from charms.reactive import RelationBase, hook, scopes
 
 
 class WSGIRequires(RelationBase):
@@ -26,6 +24,7 @@ class WSGIRequires(RelationBase):
     def changed(self):
         conv = self.conversation()
         conv.set_state("{relation_name}.connected")
+
         if conv.get_remote("enabled"):
             # this unit's conversation has a port, so
             # it is part of the set of available units
diff --git a/src/hooks/relations/telegraf-exec/requires.py b/src/hooks/relations/telegraf-exec/requires.py
index 42bb783..453203b 100644
--- a/src/hooks/relations/telegraf-exec/requires.py
+++ b/src/hooks/relations/telegraf-exec/requires.py
@@ -16,9 +16,7 @@
 
 import json
 
-from charms.reactive import hook
-from charms.reactive import RelationBase
-from charms.reactive import scopes
+from charms.reactive import RelationBase, hook, scopes
 
 
 class ExecRequires(RelationBase):
@@ -29,6 +27,7 @@ class ExecRequires(RelationBase):
         conv = self.conversation()
         conv.set_state("{relation_name}.connected")
         commands_json_dict = conv.get_remote("commands")  # list of commands to run
+
         if commands_json_dict is not None and json.loads(commands_json_dict):
             conv.set_state("{relation_name}.available")
 
@@ -40,12 +39,16 @@ class ExecRequires(RelationBase):
 
     def commands(self):
         cmds = []
+
         for conv in self.conversations():
             commands_json_dict = conv.get_remote("commands")  # list of commands dicts
+
             for cmd_info in json.loads(commands_json_dict):
                 commands = cmd_info.pop("commands", [])  # list of commands
+
                 if commands is None and "command" in cmd_info:
                     commands = [cmd_info.pop("command")]
+
                 if not commands:
                     continue
                 data_format = cmd_info.pop("data_format")  # json, graphite, influx
@@ -57,4 +60,5 @@ class ExecRequires(RelationBase):
                 cmd["run_on_this_unit"] = cmd_info.pop("run_on_this_unit", True)
                 cmd.update(cmd_info)
                 cmds.append(cmd)
+
         return cmds
diff --git a/src/reactive/__init__.py b/src/reactive/__init__.py
index e69de29..82e3dfc 100644
--- a/src/reactive/__init__.py
+++ b/src/reactive/__init__.py
@@ -0,0 +1 @@
+"""Reactive package."""
diff --git a/src/reactive/telegraf.py b/src/reactive/telegraf.py
index ba47505..4b72eab 100644
--- a/src/reactive/telegraf.py
+++ b/src/reactive/telegraf.py
@@ -16,40 +16,43 @@
 
 import base64
 import binascii
-from distutils.version import LooseVersion
 import io
 import json
 import os
+import re
 import shutil
 import socket
+import subprocess
 import sys
 import time
-import yaml
-import re
-import netifaces
-import subprocess
+from distutils.version import LooseVersion
+
+from charmhelpers import context
+from charmhelpers.contrib.charmsupport import nrpe
+from charmhelpers.core import hookenv, host, unitdata
+from charmhelpers.core.host import is_container
+from charmhelpers.core.templating import render
 
+import charms.promreg
 from charms import apt
 from charms.layer import snap
 from charms.reactive import (
+    clear_flag,
     endpoint_from_flag,
     helpers,
     hook,
-    when,
-    when_not,
     set_flag,
-    clear_flag,
     toggle_flag,
+    when,
+    when_not,
 )
 from charms.reactive.bus import get_states
 
-from charmhelpers import context
-from charmhelpers.core import hookenv, host, unitdata
-from charmhelpers.core.templating import render
-from charmhelpers.core.host import is_container
-from charmhelpers.contrib.charmsupport import nrpe
-import charms.promreg
-from jinja2 import Template, Environment, FileSystemLoader, exceptions
+from jinja2 import Environment, FileSystemLoader, Template, exceptions
+
+import netifaces
+
+import yaml
 
 DEB_BASE_DIR = "/etc/telegraf"
 SNAP_BASE_DIR = "/var/snap/telegraf/current"
@@ -75,6 +78,7 @@ class InvalidInstallMethod(Exception):
 
 def get_install_method():
     config = hookenv.config()
+
     if config["install_method"] in ["deb", "snap"]:
         return config["install_method"]
     else:
@@ -87,6 +91,7 @@ def get_install_method():
 
 def get_base_dir():
     config = hookenv.config()
+
     if config["install_method"] == "deb":
         return DEB_BASE_DIR
     elif config["install_method"] == "snap":
@@ -101,6 +106,7 @@ def get_base_dir():
 
 def get_service():
     config = hookenv.config()
+
     if config["install_method"] == "deb":
         return DEB_SERVICE
     elif config["install_method"] == "snap":
@@ -139,13 +145,16 @@ def list_config_files():
     config_files = [get_main_config_path()]
     # only include config files for configured plugins
     current_states = get_states()
+
     for plugin in list_supported_plugins():
         if "plugins.{}.configured".format(plugin) in current_states.keys():
             config_path = "{}/{}.conf".format(get_configs_dir(), plugin)
             config_files.append(config_path)
+
     if "extra_plugins.configured" in current_states.keys():
         config_files.append("{}/extra_plugins.conf".format(get_configs_dir()))
     config_files.append("{}/socket_listener.conf".format(get_configs_dir()))
+
     return config_files
 
 
@@ -153,33 +162,40 @@ def get_hostname_label():
     config = hookenv.config()
     hostname_fmt = config["hostname"]
     unit = get_remote_unit_name().replace("/", "-")  # / is invalid in labels.
+
     if hostname_fmt == "UNIT_NAME":  # Deprecated
         return unit
     env = os.environ
     model = env.get("JUJU_ENV_NAME") or env.get("JUJU_MODEL_NAME", "")
     uuid = env.get("JUJU_ENV_UUID") or env.get("JUJU_MODEL_UUID", "")
     syshost = socket.gethostname()
+
     return hostname_fmt.format(unit=unit, model=model, uuid=uuid, host=syshost)
 
 
 def get_remote_unit_name():
     unit = hookenv.principal_unit()
+
     if unit:
         # Note(aluria): use Juju env var available since 2017
+
         return unit
     else:
         # Note(aluria): lookup all available IPv4/IPv6 addresses (except lo)
         ip_addresses = set()
+
         for iface in netifaces.interfaces():
             if iface == "lo":
                 continue
             ip_addrs = netifaces.ifaddresses(iface)
+
             for iface_type in ip_addrs:
                 if iface_type in (netifaces.AF_INET, netifaces.AF_INET6):
                     for addrs in ip_addrs[iface_type]:
                         ip_addresses.add(addrs["addr"])
 
         # Note(aluria): and try to match them against rel['private-address']
+
         for rel_type in hookenv.metadata()["requires"].keys():
             for rel in hookenv.relations_of_type(rel_type):
                 if rel["private-address"] in ip_addresses:
@@ -188,6 +204,7 @@ def get_remote_unit_name():
 
 def get_base_inputs():
     """Make a structure for rendering the base_inputs template.
+
     Returns a dict of items for the template.
     """
     extra_options = get_extra_options()
@@ -195,6 +212,7 @@ def get_base_inputs():
     config = hookenv.config()
     str_disabled_plugins = config["disabled_plugins"]
     disabled_plugins = str_disabled_plugins.split(":") if str_disabled_plugins else []
+
     return {
         "extra_options": extra_options["inputs"],
         "bcache": is_bcache(),
@@ -221,20 +239,25 @@ def get_extra_options():
     # to raw json
     json_vals = {}
     # kind level
+
     for k, v in extra_options.items():
         json_vals[k] = {}
         # plugins level
+
         for plugin, values in v.items():
             json_vals[k][plugin] = {}
             # inner plugin (aka key:value)
+
             for key, val in values.items():
                 if key in ("tagpass", "tagdrop"):
                     # this is a tagpass/drop, we need to go deeper
                     json_vals[k][plugin][key] = {}
+
                     for tag, tagvalue in val.items():
                         json_vals[k][plugin][key][tag] = json.dumps(tagvalue)
                 else:
                     json_vals[k][plugin][key] = json.dumps(val)
+
     return json_vals
 
 
@@ -323,13 +346,17 @@ def render_socket_listener_config(context):
 def get_sysstat_config_with_sadc_xall(content):
     """Get updated sysstat config content with `-S XALL` in `SADC_OPTIONS`.
 
-    `/etc/sysstat/systat` consists of a sequence of shell variable assignments used to configure sysstat logging.
+    `/etc/sysstat/systat` consists of a sequence of shell variable assignments
+    used to configure sysstat logging.
 
     Check the original config content.
+
     If change needed, make the change and return new config content.
+
     If no change, return None.
     """
-    # if SADC_OPTIONS already exists with `-S XALL` in value, no need to change, return None
+    # if SADC_OPTIONS already exists with `-S XALL` in value, no need to change,
+    # return None
     if re.search(r'^SADC_OPTIONS=".*-S\s+XALL.*"', content, flags=re.M):
         return None
 
@@ -365,6 +392,7 @@ def update_sysstat_config_with_sdac_xall(path="/etc/sysstat/sysstat"):
     if os.path.isfile(path):
         with open(path, mode="r", encoding="utf8") as f:
             new_text = get_sysstat_config_with_sadc_xall(f.read())
+
         if new_text:
             hookenv.log("updating {} to ensure `-S XALL` in SADC_OPTIONS".format(path))
             with open(path, mode="w", encoding="utf8") as f:
@@ -386,18 +414,23 @@ def configure_telegraf():  # noqa: C901
             "blocked",
             "Wrong install_method provided: {!r}".format(config["install_method"]),
         )
+
         return
+
     if get_remote_unit_name() is None:
         hookenv.status_set("waiting", "Waiting for juju-info relation")
         # if UNIT_NAME in hostname config and relation not yet available,
         # make telegraf unable to start to not get weird metrics names
+
         if os.path.exists(config_path):
             os.unlink(config_path)
+
         return
 
     inputs = config.get("inputs_config", "")
     outputs = config.get("outputs_config", "")
     # just for the migration out of base64
+
     if inputs:
         try:
             inputs = base64.b64decode(inputs.encode("utf-8"), validate=True).decode(
@@ -406,6 +439,7 @@ def configure_telegraf():  # noqa: C901
         except binascii.Error:
             # not bas64, probably already up to date configs
             pass
+
     if outputs:
         try:
             outputs = base64.b64decode(outputs.encode("utf-8"), validate=True).decode(
@@ -415,6 +449,7 @@ def configure_telegraf():  # noqa: C901
             # not bas64, probably already up to date configs
             pass
     tags = []
+
     if config["tags"]:
         for tag in config["tags"].split(","):
             key, value = tag.split("=")
@@ -424,11 +459,13 @@ def configure_telegraf():  # noqa: C901
     tags.append('juju_unit = "{}"'.format(get_remote_unit_name().replace("/", "-")))
     tags.append('juju_model = "{}"'.format(hookenv.model_name()))
     context["tags"] = tags
+
     if inputs:
         context["inputs"] = inputs
     else:
         # use base inputs from charm templates
         context["inputs"] = render_base_inputs()
+
     if outputs:
         context["outputs"] = outputs
     else:
@@ -438,12 +475,13 @@ def configure_telegraf():  # noqa: C901
     context["hostname"] = get_hostname_label()
 
     logfile_path = os.path.normpath(context["logfile"])
+
     if (
         context["logfile"]
-        and not logfile_path.startswith("/var/log/")
-        and not (
+        and not logfile_path.startswith("/var/log/")  # noqa W503
+        and not (  # noqa W503
             config["install_method"] == "snap"
-            and logfile_path.startswith("/var/snap/telegraf/common/")
+            and logfile_path.startswith("/var/snap/telegraf/common/")  # noqa W503
         )
     ):
         # only allow logging in /var/log, syslog, or /var/snap/telegraf/common
@@ -487,6 +525,7 @@ def configure_telegraf():  # noqa: C901
     )
 
     # add sudoers file for telegraf if openvswitch is running
+
     if host.service_running("openvswitch-switch"):
         sudoers_filename = "telegraf_sudoers"
         src = os.path.join(get_files_dir(), sudoers_filename)
@@ -508,6 +547,7 @@ def configure_telegraf():  # noqa: C901
 
     set_flag("telegraf.configured")
     set_flag("telegraf.needs_reload")
+
     if config["install_method"] == "deb":
         set_flag("telegraf.apt.configured")
     else:
@@ -525,12 +565,15 @@ def install_telegraf():
         hookenv.status_set(
             "blocked", "Wrong install_method provided. Expected either 'deb' or 'snap'."
         )
+
         return
+
     if install_method == "deb":
         try:
             snap.remove("telegraf")
         except Exception:
-            # the snap may already be absent, or snaps may not even be supported in this environment
+            # the snap may already be absent, or snaps may not even be supported
+            # in this environment
             pass
         apt.queue_install(["telegraf"])
     elif install_method == "snap":
@@ -538,6 +581,7 @@ def install_telegraf():
         config = hookenv.config()
         snap_channel = config.get("snap_channel")
         snap.install("telegraf", channel=snap_channel, classic=True)
+
     if install_method:
         set_flag("telegraf.installed")
 
@@ -572,16 +616,19 @@ def upgrade_charm():
 @when("config.changed")
 def handle_config_changes():
     config = hookenv.config()
+
     if config.changed("extra_options"):
         for plugin in list_supported_plugins():
             clear_flag("plugins.{}.configured".format(plugin))
     # if something else changed, let's reconfigure telegraf itself just in case
+
     if config.changed("extra_plugins"):
         clear_flag("extra_plugins.configured")
+
     if (
         config.changed("install_method")
-        or config.changed("snap_channel")
-        or config.changed("install_sources")
+        or config.changed("snap_channel")  # noqa W503
+        or config.changed("install_sources")  # noqa W503
     ):
         clear_flag("telegraf.installed")
     clear_flag("telegraf.configured")
@@ -595,6 +642,7 @@ def handle_config_changes():
 def configure_extra_plugins():
     config = hookenv.config()
     plugins = config["extra_plugins"]
+
     if plugins:
         config_path = "{}/extra_plugins.conf".format(get_configs_dir())
         host.write_file(config_path, plugins.encode("utf-8"))
@@ -894,7 +942,7 @@ def redis_input(redis):
   servers = ["tcp://{{ host }}:{{ port }}"]
   # Until https://github.com/influxdata/telegraf/issues/5036 is fixed
   fielddrop = ["aof_last_bgrewrite_status","aof_last_write_status","maxmemory_policy","rdb_last_bgsave_status","used_memory_dataset_perc","used_memory_peak_perc"]
-"""
+"""  # noqa E501 (inline template)
     config_path = "{}/{}.conf".format(get_configs_dir(), "redis")
 
     rels = hookenv.relations_of_type("redis")
@@ -1146,7 +1194,8 @@ def prometheus_client(prometheus):
 
 
 def convert_days(time_string):
-    """
+    """Convert string time descript to days.
+
     Function to convert strings like 2w or 14d to a sting containing the number
     of days.
 
@@ -1302,8 +1351,8 @@ def start_or_restart():
     active_plugins_changed = helpers.data_changed("active_plugins", states or "")
     if (
         not host.service_running(service)
-        or config_files_changed
-        or active_plugins_changed
+        or config_files_changed  # noqa W503
+        or active_plugins_changed  # noqa W503
     ):
         hookenv.log("Restarting telegraf")
         host.service_restart(service)
@@ -1328,8 +1377,9 @@ def start_or_restart():
 
 
 def is_bcache():
-    """
-    return true if bcache is present, and this is not a container
+    """Determine if this is a container.
+
+    return true if bcache is present, and this is not a container.
     """
     container = is_container()
     return os.path.exists("/sys/fs/bcache") and not container
@@ -1352,9 +1402,10 @@ def update_status():
 @when_not("telegraf.nagios-setup.complete")
 def configure_nagios(nagios):
     """Configure nagios process check.
-    the flag 'telegraf.nagios-setup.complete' is reset at the moment config is
-    changed, so this should make sure that updates are handled."""
 
+    The flag 'telegraf.nagios-setup.complete' is reset at the moment config is
+    changed, so this should make sure that updates are handled.
+    """
     # Use charmhelpers to handle the configuration of nrpe
     hostname = nrpe.get_nagios_hostname()
     nrpe_setup = nrpe.NRPE(hostname=hostname, primary=False)
diff --git a/src/tests/functional/tests/test_telegraf.py b/src/tests/functional/tests/test_telegraf.py
index 1b80661..3c4354d 100644
--- a/src/tests/functional/tests/test_telegraf.py
+++ b/src/tests/functional/tests/test_telegraf.py
@@ -21,9 +21,8 @@ import unittest
 
 import requests
 
-from zaza.utilities import juju
 from zaza import model
-
+from zaza.utilities import juju
 
 DEFAULT_HTTPGET_TIMEOUT = 10
 DEFAULT_RETRIES = 12
@@ -58,21 +57,24 @@ class TestTelegraf(BaseTelegrafTest):
             model.get_units(app)
             for app in juju.get_principle_applications(self.application_name)
         )
+
         for unit in it.chain.from_iterable(principal_units):
             if not unit.public_address:
                 continue
             url = "http://{}:{}/metrics".format(
                 unit.public_address, DEFAULT_TELEGRAF_EXPORTER_PORT
             )
+
             for retry in range(DEFAULT_RETRIES):
                 resp = requests.get(url, timeout=DEFAULT_HTTPGET_TIMEOUT)
                 self.assertEqual(resp.status_code, 200)
 
                 if (
                     unit.name.startswith("postgresql/")
-                    and "postgresql_blks_hit" not in resp.text
+                    and "postgresql_blks_hit" not in resp.text  # noqa W503
                 ) or "cpu_usage_idle" not in resp.text:
                     time.sleep(DEFAULT_RETRIES_TIMEOUT)
+
                     continue
 
                 logging.info("test_service: Unit {} is reachable".format(unit.name))
@@ -90,6 +92,7 @@ class TestTelegraf(BaseTelegrafTest):
                     r"^zoneinfo_",
                     r"^processes_",
                 ]
+
                 for re_pattern in re_patterns:
                     self.check_re_pattern(re_pattern, text)
 
@@ -104,12 +107,14 @@ class TestTelegraf(BaseTelegrafTest):
         install_method = model.get_application_config("telegraf")["install_method"][
             "value"
         ]
+
         if install_method == "deb":
             telegraf_conf = DEB_TELEGRAF_CONF
         else:
             telegraf_conf = SNAP_TELEGRAF_CONF
         cmd = "cat {}".format(telegraf_conf)
         response = model.run_on_unit(self.lead_unit_name, cmd)
+
         if response["Code"] != "0":
             self.fail(
                 "test_02_telegraf_logfile: could not read file {}".format(telegraf_conf)
@@ -118,6 +123,7 @@ class TestTelegraf(BaseTelegrafTest):
         for line in response["Stdout"].splitlines():
             if line.strip() == 'logfile = "/var/log/telegraf/telegraf.log"':
                 logging.info("test_02_telegraf_logfile: logfile config parameter found")
+
                 return
 
         self.fail(
@@ -127,25 +133,32 @@ class TestTelegraf(BaseTelegrafTest):
         )
 
     def test_03_system_service(self):
-        """Check that the right service is running, e.g. either the deb's or the snap's."""
+        """Check that the right service is running.
+
+        e.g. either the deb's or the snap's.
+        """
         install_method = model.get_application_config("telegraf")["install_method"][
             "value"
         ]
         services = {"deb": "telegraf", "snap": "snap.telegraf.telegraf"}
+
         for method in services.keys():
             service = services[method]
             cmd = "service {} status".format(service)
             response = model.run_on_unit(self.lead_unit_name, cmd)
+
             if install_method == method and response["Code"] != "0":
                 self.fail(
-                    "test_03_system_service: service {} should be running on {} but is not. "
+                    "test_03_system_service: service {} should be running "
+                    "on {} but is not. "
                     "install_method is {}.".format(
                         service, self.lead_unit_name, install_method
                     )
                 )
             elif install_method != method and response["Code"] == "0":
                 self.fail(
-                    "test_03_system_service: service {}  is running on {} but shouldn't. "
+                    "test_03_system_service: service {}  is running "
+                    "on {} but shouldn't. "
                     "install_method is {}.".format(
                         service, self.lead_unit_name, install_method
                     )
diff --git a/src/tests/unit/__init__.py b/src/tests/unit/__init__.py
index 28e9795..5f22a2b 100644
--- a/src/tests/unit/__init__.py
+++ b/src/tests/unit/__init__.py
@@ -1,3 +1,5 @@
+"""Unit test module."""
+
 import sys
 
 sys.path.append(".")
diff --git a/src/tests/unit/test_mysql.py b/src/tests/unit/test_mysql.py
index 27f206d..9015600 100644
--- a/src/tests/unit/test_mysql.py
+++ b/src/tests/unit/test_mysql.py
@@ -22,10 +22,11 @@ from unittest.mock import ANY, MagicMock, patch, sentinel
 # Mock layer modules
 import charms
 
+import reactive
+
 promreg = MagicMock()
 charms.promreg = promreg
 sys.modules["charms.promreg"] = promreg
-import reactive
 
 
 class TestMySQL(unittest.TestCase):
diff --git a/src/tests/unit/test_postgresql.py b/src/tests/unit/test_postgresql.py
index 9192ea4..c011b32 100644
--- a/src/tests/unit/test_postgresql.py
+++ b/src/tests/unit/test_postgresql.py
@@ -17,7 +17,7 @@
 import os
 import sys
 import unittest
-from unittest.mock import ANY, call, MagicMock, patch, sentinel
+from unittest.mock import ANY, MagicMock, call, patch, sentinel
 
 # Mock layer modules
 import charms
@@ -32,8 +32,8 @@ sys.modules["charms.apt"] = apt
 sys.modules["charms.layer"] = layer
 sys.modules["charms.promreg"] = promreg
 
-import reactive
-from reactive import telegraf
+import reactive  # noqa E402
+from reactive import telegraf  # noqa E402
 
 
 class TestPostgreSQL(unittest.TestCase):
@@ -123,7 +123,7 @@ class TestPostgreSQL(unittest.TestCase):
         get_base_dir.return_value = "/etc/telegraf"
 
         reactive.telegraf.render_postgresql_tmpl(
-            [{"replica": "master", "conn_str": "my_conn_str", "server": "my_server"},]
+            [{"replica": "master", "conn_str": "my_conn_str", "server": "my_server"}]
         )
 
         write_file.assert_called_once_with(
diff --git a/src/tests/unit/test_telegraf.py b/src/tests/unit/test_telegraf.py
index 1825fa6..57e7e3c 100644
--- a/src/tests/unit/test_telegraf.py
+++ b/src/tests/unit/test_telegraf.py
@@ -14,36 +14,38 @@
 # You should have received a copy of the GNU General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-"""actions.py tests"""
+"""Tests for actions.py."""
 import base64
-import os
 import getpass
 import grp
 import json
-import sys
+import os
 import subprocess
+import sys
 import unittest
 from textwrap import dedent
-from unittest.mock import patch, MagicMock, call
 from unittest import mock
+from unittest.mock import MagicMock, call, patch
 
-import yaml
-import pytest
-import py
-
-from charms.reactive import bus, helpers, RelationBase, set_flag
 from charmhelpers.core.hookenv import Config
 from charmhelpers.core.templating import render
 
-# Mock layer modules
 import charms
+from charms.reactive import RelationBase, bus, helpers, set_flag
+
+import py
 
+import pytest
+
+import yaml
+
+# Mock layer modules
 promreg = MagicMock()
 charms.promreg = promreg
 sys.modules["charms.promreg"] = promreg
 
-import reactive
-from reactive import telegraf
+import reactive  # noqa E402
+from reactive import telegraf  # noqa E402
 
 UNIT_TESTS_DIR = os.path.dirname(os.path.abspath(__file__))
 UNIT_TESTS_DATA_DIR = os.path.join(UNIT_TESTS_DIR, "data")
@@ -71,6 +73,7 @@ def setup(monkeypatch, tmpdir):
         # fix the args to use non-root, this is for callers that pass
         # owner/group as positional arguments like
         # charmhelpers.core.templating.render
+
         if len(a) > 2:
             if a[2] == "root" and a[3] == "root":
                 # make all files writable by owner, as we need don't run as root
@@ -80,6 +83,7 @@ def setup(monkeypatch, tmpdir):
             kw["group"] = group
             # make all files writable by owner, as we need don't run as root
             kw["perms"] = 0o744
+
         return orig_write_file(*a, **kw)
 
     monkeypatch.setattr(telegraf.host, "write_file", intercept_write_file)
@@ -94,6 +98,7 @@ def cleanup(request):
         unitdata._KV = None
         # rm unit-state.db file
         unit_state_db = os.path.join(telegraf.hookenv.charm_dir(), ".unit-state.db")
+
         if os.path.exists(unit_state_db):
             os.unlink(unit_state_db)
 
@@ -134,6 +139,7 @@ def config(monkeypatch, temp_charm_dir):
     data = dict((k, v["default"]) for k, v in raw_config["options"].items())
     config = Config(data)
     monkeypatch.setattr(telegraf.hookenv, "config", lambda: config)
+
     return config
 
 
@@ -147,13 +153,14 @@ def configs_dir():
 
 
 def persist_state():
-    """Fake persistent state by calling helpers that modify unitdata.kv"""
+    """Fake persistent state by calling helpers that modify unitdata.kv."""
     states = [
         k
         for k in bus.get_states().keys()
         if k.startswith("plugins") or k.startswith("extra_plugins")
     ]
     helpers.any_file_changed(telegraf.list_config_files())
+
     if states:
         helpers.data_changed("active_plugins", states)
 
@@ -169,7 +176,7 @@ def check_sysstat_config(original, expected):
 
 
 def test_sadc_options_correct(monkeypatch):
-    """If SADC_OPTIONS is already correct, should return None"""
+    """If SADC_OPTIONS is already correct, should return None."""
     original = dedent(
         """
         # some comment
@@ -183,7 +190,7 @@ def test_sadc_options_correct(monkeypatch):
 
 
 def test_sadc_options_correct_included(monkeypatch):
-    """If SADC_OPTIONS already includes `-S XALL`, should return None"""
+    """If SADC_OPTIONS already includes `-S XALL`, should return None."""
     original = dedent(
         """
         # some comment
@@ -197,7 +204,7 @@ def test_sadc_options_correct_included(monkeypatch):
 
 
 def test_sadc_options_non_exist(monkeypatch):
-    """If SADC_OPTIONS doesn't exist, should just append"""
+    """If SADC_OPTIONS doesn't exist, should just append."""
     original = dedent(
         """
         # some comment
@@ -217,7 +224,7 @@ def test_sadc_options_non_exist(monkeypatch):
 
 
 def test_sadc_options_commented(monkeypatch):
-    """If SADC_OPTIONS exists but commented, should ignore and append"""
+    """If SADC_OPTIONS exists but commented, should ignore and append."""
     original = dedent(
         """
         # some comment
@@ -243,7 +250,7 @@ def test_sadc_options_commented(monkeypatch):
 
 
 def test_sadc_options_incorrect(monkeypatch):
-    """If SADC_OPTIONS exists but not XALL, should replace"""
+    """If SADC_OPTIONS exists but not XALL, should replace."""
     original = dedent(
         """
         # some comment
@@ -267,7 +274,7 @@ def test_sadc_options_incorrect(monkeypatch):
 
 
 def test_sadc_options_incorrect_included(monkeypatch):
-    """If SADC_OPTIONS exists but not XALL, should replace"""
+    """If SADC_OPTIONS exists but not XALL, should replace."""
     original = dedent(
         """
         # some comment
@@ -291,7 +298,7 @@ def test_sadc_options_incorrect_included(monkeypatch):
 
 
 def test_sadc_options_commented_line_not_touched(monkeypatch):
-    """If SADC_OPTIONS exists but has no -S, should append"""
+    """If SADC_OPTIONS exists but has no -S, should append."""
     original = dedent(
         """
         # some comment
@@ -318,7 +325,7 @@ def test_sadc_options_commented_line_not_touched(monkeypatch):
 
 
 def test_sadc_options_s_missing(monkeypatch):
-    """If SADC_OPTIONS exists but has no -S, should append"""
+    """If SADC_OPTIONS exists but has no -S, should append."""
     original = dedent(
         """
         # some comment
@@ -351,6 +358,7 @@ def test_telegraf_exec_metrics(monkeypatch, temp_config_dir):
     metrics = set(
         ["sockstat", "sockstat6", "softnet_stat", "buddyinfo", "zoneinfo", "netns"]
     )
+
     for metric in metrics:
         run_telegraf_exec_metrics("--metric", metric)
 
@@ -370,9 +378,8 @@ def test_telegraf_exec_metrics(monkeypatch, temp_config_dir):
     )
 
     # ensure config files exists after render
-    run_telegraf_exec_metrics(
-        "--render-config-files", "--configs-dir", configs_dir(),
-    )
+    run_telegraf_exec_metrics("--render-config-files", "--configs-dir", configs_dir())
+
     for metric in metrics:
         assert os.path.isfile(os.path.join(configs_dir(), "{}.conf".format(metric)))
 
@@ -386,9 +393,11 @@ def test_telegraf_exec_metrics(monkeypatch, temp_config_dir):
         ":".join(disabled_metrics),
     )
     # config files for disabled metrics should be removed.
+
     for metric in disabled_metrics:
         assert not os.path.isfile(os.path.join(configs_dir(), "{}.conf".format(metric)))
     # config files for other metrics should still be there
+
     for metric in metrics - disabled_metrics:
         assert os.path.isfile(os.path.join(configs_dir(), "{}.conf".format(metric)))
 
@@ -619,7 +628,7 @@ inputs:
 
 
 def test_base_inputs_disabled_plugins(config):
-    """Check disabled_plugins option is working for builtin inputs"""
+    """Check disabled_plugins option is working for builtin inputs."""
     config["disabled_plugins"] = "cpu:disk"
     content = telegraf.render_base_inputs()
 
@@ -1246,7 +1255,7 @@ class TestGrafanaDashboard(unittest.TestCase):
             variable_end_string=">>",
         )
         mock_grafana.register_dashboard.assert_called_once_with(
-            name=telegraf.GRAFANA_DASHBOARD_NAME, dashboard=mock_dashboard_dict,
+            name=telegraf.GRAFANA_DASHBOARD_NAME, dashboard=mock_dashboard_dict
         )
         mock_set_flag.assert_called_once_with("grafana.configured")
 
diff --git a/src/tox.ini b/src/tox.ini
index 40c62d6..4977737 100644
--- a/src/tox.ini
+++ b/src/tox.ini
@@ -42,7 +42,8 @@ exclude =
     charmhelpers,
     mod,
     .build
-ignore = I100, D101, D102, D103, I201, D205, W504, D400, D401, D403, D209, D100, E403, I101, E501, N803, E226, E128, D200, E741, D202, E261, E402, D104, W503, E231  # TODO
+#ignore = I100, D101, D102, D103, I201, D205, W504, D400, D401, D403, D209, D100, E403, I101, E501, N803, E226, E128, D200, E741, D202, E261, E402, D104, W503, E231  # TODO
+ignore = D100, D101, D102, D103
 
 max-line-length = 88
 max-complexity = 10