Major improvement in OSM charms

- Adapt all new operator charms to use the same pattern. They are all
using now this library that encapsulates the common logic for all
charms: https://github.com/davigar15/ops-lib-charmed-osm. That will be
eventually moved to gitlab, when it has a PyPI repository available
- Add unit tests to all charms
- Modify installer and bundles to point to the new charms
- Improve the build.sh script for building the charms

Change-Id: I0896ceb082d1b6a76b3560c07482a4135a220a3f
Signed-off-by: David Garcia <david.garcia@canonical.com>
diff --git a/installers/charm/mon/.gitignore b/installers/charm/mon/.gitignore
index 0be86d6..2885df2 100644
--- a/installers/charm/mon/.gitignore
+++ b/installers/charm/mon/.gitignore
@@ -1,4 +1,4 @@
-# Copyright 2020 Canonical Ltd.
+# Copyright 2021 Canonical Ltd.
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
 # not use this file except in compliance with the License. You may obtain
@@ -22,7 +22,9 @@
 venv
 .vscode
 build
-mon.charm
+*.charm
 .coverage
+coverage.xml
 .stestr
 cover
+release
\ No newline at end of file
diff --git a/installers/charm/mon/.jujuignore b/installers/charm/mon/.jujuignore
new file mode 100644
index 0000000..bf04eb4
--- /dev/null
+++ b/installers/charm/mon/.jujuignore
@@ -0,0 +1,28 @@
+# Copyright 2021 Canonical Ltd.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+# For those usages not covered by the Apache License, Version 2.0 please
+# contact: legal@canonical.com
+#
+# To get in touch with the maintainers, please contact:
+# osm-charmers@lists.launchpad.net
+##
+
+venv
+.vscode
+build
+prometheus.charm
+.coverage
+.stestr
+cover
diff --git a/installers/charm/mon/.yamllint.yaml b/installers/charm/mon/.yamllint.yaml
index c20ac8d..d71fb69 100644
--- a/installers/charm/mon/.yamllint.yaml
+++ b/installers/charm/mon/.yamllint.yaml
@@ -1,4 +1,4 @@
-# Copyright 2020 Canonical Ltd.
+# Copyright 2021 Canonical Ltd.
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
 # not use this file except in compliance with the License. You may obtain
@@ -28,6 +28,7 @@
   - ".yamllint"
 ignore: |
   .tox
+  cover/
   build/
-  mod/
-  lib/
+  venv
+  release/
diff --git a/installers/charm/mon/config.yaml b/installers/charm/mon/config.yaml
index 9480ea7..93d77fe 100644
--- a/installers/charm/mon/config.yaml
+++ b/installers/charm/mon/config.yaml
@@ -60,3 +60,15 @@
     type: string
     description: "The VCA cacert."
     default: ""
+  grafana_url:
+    description: Grafana URL
+    type: string
+    default: http://grafana:3000
+  grafana_user:
+    description: Grafana user
+    type: string
+    default: admin
+  grafana_password:
+    description: Grafana password
+    type: string
+    default: admin
diff --git a/installers/charm/mon/requirements-test.txt b/installers/charm/mon/requirements-test.txt
new file mode 100644
index 0000000..d7585f3
--- /dev/null
+++ b/installers/charm/mon/requirements-test.txt
@@ -0,0 +1,31 @@
+# Copyright 2021 Canonical Ltd.
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+# For those usages not covered by the Apache License, Version 2.0 please
+# contact: legal@canonical.com
+#
+# To get in touch with the maintainers, please contact:
+# osm-charmers@lists.launchpad.net
+##
+-r requirements.txt
+coverage
+stestr
+mock
+black
+yamllint
+flake8
+safety
+requests-mock
+asynctest
+nose2
\ No newline at end of file
diff --git a/installers/charm/mon/requirements.txt b/installers/charm/mon/requirements.txt
index a26601f..f10a199 100644
--- a/installers/charm/mon/requirements.txt
+++ b/installers/charm/mon/requirements.txt
@@ -1,4 +1,4 @@
-# Copyright 2020 Canonical Ltd.
+# Copyright 2021 Canonical Ltd.
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
 # not use this file except in compliance with the License. You may obtain
@@ -19,5 +19,4 @@
 # osm-charmers@lists.launchpad.net
 ##
 
-ops
-git+https://github.com/juju-solutions/resource-oci-image/@c5778285d332edf3d9a538f9d0c06154b7ec1b0b#egg=oci-image
+git+https://github.com/davigar15/ops-lib-charmed-osm/@e7f26cd29b322e175a23cadbe4546b7f2bbf111c
\ No newline at end of file
diff --git a/installers/charm/mon/src/charm.py b/installers/charm/mon/src/charm.py
index f51213d..98c3297 100755
--- a/installers/charm/mon/src/charm.py
+++ b/installers/charm/mon/src/charm.py
@@ -1,5 +1,5 @@
 #!/usr/bin/env python3
-# Copyright 2020 Canonical Ltd.
+# Copyright 2021 Canonical Ltd.
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
 # not use this file except in compliance with the License. You may obtain
@@ -20,254 +20,135 @@
 # osm-charmers@lists.launchpad.net
 ##
 
+# pylint: disable=E0213
+
+
 import logging
-from typing import Any, Dict, NoReturn
+from typing import NoReturn
 
-from ops.charm import CharmBase, CharmEvents
-from ops.framework import EventBase, EventSource, StoredState
 from ops.main import main
-from ops.model import ActiveStatus, BlockedStatus, MaintenanceStatus
-from oci_image import OCIImageResource, OCIImageResourceError
 
-from pod_spec import make_pod_spec
+from opslib.osm.charm import CharmedOsmBase, RelationsMissing
 
-LOGGER = logging.getLogger(__name__)
+from opslib.osm.pod import (
+    ContainerV3Builder,
+    PodSpecV3Builder,
+)
 
-MON_PORT = 8000
+from opslib.osm.validator import (
+    ModelValidator,
+    validator,
+)
+
+from opslib.osm.interfaces.kafka import KafkaClient
+from opslib.osm.interfaces.mongo import MongoClient
+from opslib.osm.interfaces.prometheus import PrometheusClient
 
 
-class ConfigurePodEvent(EventBase):
-    """Configure Pod event"""
+logger = logging.getLogger(__name__)
 
-    pass
+PORT = 8000
 
 
-class MonEvents(CharmEvents):
-    """MON Events"""
+class ConfigModel(ModelValidator):
+    vca_host: str
+    vca_user: str
+    vca_password: str
+    vca_cacert: str
+    database_commonkey: str
+    log_level: str
+    openstack_default_granularity: int
+    global_request_timeout: int
+    collector_interval: int
+    evaluator_interval: int
+    grafana_url: str
+    grafana_user: str
+    grafana_password: str
 
-    configure_pod = EventSource(ConfigurePodEvent)
+    @validator("log_level")
+    def validate_log_level(cls, v):
+        if v not in {"INFO", "DEBUG"}:
+            raise ValueError("value must be INFO or DEBUG")
+        return v
 
 
-class MonCharm(CharmBase):
-    """MON Charm."""
-
-    state = StoredState()
-    on = MonEvents()
-
+class MonCharm(CharmedOsmBase):
     def __init__(self, *args) -> NoReturn:
-        """MON Charm constructor."""
-        super().__init__(*args)
+        super().__init__(*args, oci_image="image")
 
-        # Internal state initialization
-        self.state.set_default(pod_spec=None)
+        self.kafka_client = KafkaClient(self, "kafka")
+        self.framework.observe(self.on["kafka"].relation_changed, self.configure_pod)
+        self.framework.observe(self.on["kafka"].relation_broken, self.configure_pod)
 
-        # Message bus data initialization
-        self.state.set_default(message_host=None)
-        self.state.set_default(message_port=None)
+        self.mongodb_client = MongoClient(self, "mongodb")
+        self.framework.observe(self.on["mongodb"].relation_changed, self.configure_pod)
+        self.framework.observe(self.on["mongodb"].relation_broken, self.configure_pod)
 
-        # Database data initialization
-        self.state.set_default(database_uri=None)
-
-        # Prometheus data initialization
-        self.state.set_default(prometheus_host=None)
-        self.state.set_default(prometheus_port=None)
-
-        self.port = MON_PORT
-        self.image = OCIImageResource(self, "image")
-
-        # Registering regular events
-        self.framework.observe(self.on.start, self.configure_pod)
-        self.framework.observe(self.on.config_changed, self.configure_pod)
-        self.framework.observe(self.on.upgrade_charm, self.configure_pod)
-
-        # Registering custom internal events
-        self.framework.observe(self.on.configure_pod, self.configure_pod)
-
-        # Registering required relation events
+        self.prometheus_client = PrometheusClient(self, "prometheus")
         self.framework.observe(
-            self.on.kafka_relation_changed, self._on_kafka_relation_changed
+            self.on["prometheus"].relation_changed, self.configure_pod
         )
         self.framework.observe(
-            self.on.mongodb_relation_changed, self._on_mongodb_relation_changed
-        )
-        self.framework.observe(
-            self.on.prometheus_relation_changed, self._on_prometheus_relation_changed
+            self.on["prometheus"].relation_broken, self.configure_pod
         )
 
-        # Registering required relation departed events
-        self.framework.observe(
-            self.on.kafka_relation_departed, self._on_kafka_relation_departed
-        )
-        self.framework.observe(
-            self.on.mongodb_relation_departed, self._on_mongodb_relation_departed
-        )
-        self.framework.observe(
-            self.on.prometheus_relation_departed, self._on_prometheus_relation_departed
+    def _check_missing_dependencies(self, config: ConfigModel):
+        missing_relations = []
+
+        if self.kafka_client.is_missing_data_in_unit():
+            missing_relations.append("kafka")
+        if self.mongodb_client.is_missing_data_in_unit():
+            missing_relations.append("mongodb")
+        if self.prometheus_client.is_missing_data_in_app():
+            missing_relations.append("prometheus")
+
+        if missing_relations:
+            raise RelationsMissing(missing_relations)
+
+    def build_pod_spec(self, image_info):
+        # Validate config
+        config = ConfigModel(**dict(self.config))
+        # Check relations
+        self._check_missing_dependencies(config)
+        # Create Builder for the PodSpec
+        pod_spec_builder = PodSpecV3Builder()
+        # Build Container
+        container_builder = ContainerV3Builder(self.app.name, image_info)
+        container_builder.add_port(name=self.app.name, port=PORT)
+        container_builder.add_envs(
+            {
+                # General configuration
+                "ALLOW_ANONYMOUS_LOGIN": "yes",
+                "OSMMON_OPENSTACK_DEFAULT_GRANULARITY": config.openstack_default_granularity,
+                "OSMMON_GLOBAL_REQUEST_TIMEOUT": config.global_request_timeout,
+                "OSMMON_GLOBAL_LOGLEVEL": config.log_level,
+                "OSMMON_COLLECTOR_INTERVAL": config.collector_interval,
+                "OSMMON_EVALUATOR_INTERVAL": config.evaluator_interval,
+                # Kafka configuration
+                "OSMMON_MESSAGE_DRIVER": "kafka",
+                "OSMMON_MESSAGE_HOST": self.kafka_client.host,
+                "OSMMON_MESSAGE_PORT": self.kafka_client.port,
+                # Database configuration
+                "OSMMON_DATABASE_DRIVER": "mongo",
+                "OSMMON_DATABASE_URI": self.mongodb_client.connection_string,
+                "OSMMON_DATABASE_COMMONKEY": config.database_commonkey,
+                # Prometheus configuration
+                "OSMMON_PROMETHEUS_URL": f"http://{self.prometheus_client.hostname}:{self.prometheus_client.port}",
+                # VCA configuration
+                "OSMMON_VCA_HOST": config.vca_host,
+                "OSMMON_VCA_USER": config.vca_user,
+                "OSMMON_VCA_SECRET": config.vca_password,
+                "OSMMON_VCA_CACERT": config.vca_cacert,
+                "OSMMON_GRAFANA_URL": config.grafana_url,
+                "OSMMON_GRAFANA_USER": config.grafana_user,
+                "OSMMON_GRAFANA_PASSWORD": config.grafana_password,
+            }
         )
 
-    def _on_kafka_relation_changed(self, event: EventBase) -> NoReturn:
-        """Reads information about the kafka relation.
-
-        Args:
-            event (EventBase): Kafka relation event.
-        """
-        message_host = event.relation.data[event.unit].get("host")
-        message_port = event.relation.data[event.unit].get("port")
-
-        if (
-            message_host
-            and message_port
-            and (
-                self.state.message_host != message_host
-                or self.state.message_port != message_port
-            )
-        ):
-            self.state.message_host = message_host
-            self.state.message_port = message_port
-            self.on.configure_pod.emit()
-
-    def _on_kafka_relation_departed(self, event: EventBase) -> NoReturn:
-        """Clear kafka relation data.
-
-        Args:
-            event (EventBase): Kafka relation event.
-        """
-        self.state.message_host = None
-        self.state.message_port = None
-        self.on.configure_pod.emit()
-
-    def _on_mongodb_relation_changed(self, event: EventBase) -> NoReturn:
-        """Reads information about the DB relation.
-
-        Args:
-            event (EventBase): DB relation event.
-        """
-        database_uri = event.relation.data[event.unit].get("connection_string")
-
-        if database_uri and self.state.database_uri != database_uri:
-            self.state.database_uri = database_uri
-            self.on.configure_pod.emit()
-
-    def _on_mongodb_relation_departed(self, event: EventBase) -> NoReturn:
-        """Clear mongodb relation data.
-
-        Args:
-            event (EventBase): DB relation event.
-        """
-        self.state.database_uri = None
-        self.on.configure_pod.emit()
-
-    def _on_prometheus_relation_changed(self, event: EventBase) -> NoReturn:
-        """Reads information about the prometheus relation.
-
-        Args:
-            event (EventBase): Prometheus relation event.
-        """
-        prometheus_host = event.relation.data[event.unit].get("hostname")
-        prometheus_port = event.relation.data[event.unit].get("port")
-
-        if (
-            prometheus_host
-            and prometheus_port
-            and (
-                self.state.prometheus_host != prometheus_host
-                or self.state.prometheus_port != prometheus_port
-            )
-        ):
-            self.state.prometheus_host = prometheus_host
-            self.state.prometheus_port = prometheus_port
-            self.on.configure_pod.emit()
-
-    def _on_prometheus_relation_departed(self, event: EventBase) -> NoReturn:
-        """Clear prometheus relation data.
-
-        Args:
-            event (EventBase): Prometheus relation event.
-        """
-        self.state.prometheus_host = None
-        self.state.prometheus_port = None
-        self.on.configure_pod.emit()
-
-    def _missing_relations(self) -> str:
-        """Checks if there missing relations.
-
-        Returns:
-            str: string with missing relations
-        """
-        data_status = {
-            "kafka": self.state.message_host,
-            "mongodb": self.state.database_uri,
-            "prometheus": self.state.prometheus_host,
-        }
-
-        missing_relations = [k for k, v in data_status.items() if not v]
-
-        return ", ".join(missing_relations)
-
-    @property
-    def relation_state(self) -> Dict[str, Any]:
-        """Collects relation state configuration for pod spec assembly.
-
-        Returns:
-            Dict[str, Any]: relation state information.
-        """
-        relation_state = {
-            "message_host": self.state.message_host,
-            "message_port": self.state.message_port,
-            "database_uri": self.state.database_uri,
-            "prometheus_host": self.state.prometheus_host,
-            "prometheus_port": self.state.prometheus_port,
-        }
-
-        return relation_state
-
-    def configure_pod(self, event: EventBase) -> NoReturn:
-        """Assemble the pod spec and apply it, if possible.
-
-        Args:
-            event (EventBase): Hook or Relation event that started the
-                               function.
-        """
-        if missing := self._missing_relations():
-            self.unit.status = BlockedStatus(
-                "Waiting for {0} relation{1}".format(
-                    missing, "s" if "," in missing else ""
-                )
-            )
-            return
-
-        if not self.unit.is_leader():
-            self.unit.status = ActiveStatus("ready")
-            return
-
-        self.unit.status = MaintenanceStatus("Assembling pod spec")
-
-        # Fetch image information
-        try:
-            self.unit.status = MaintenanceStatus("Fetching image information")
-            image_info = self.image.fetch()
-        except OCIImageResourceError:
-            self.unit.status = BlockedStatus("Error fetching image information")
-            return
-
-        try:
-            pod_spec = make_pod_spec(
-                image_info,
-                self.model.config,
-                self.relation_state,
-                self.model.app.name,
-                self.port,
-            )
-        except ValueError as exc:
-            LOGGER.exception("Config/Relation data validation error")
-            self.unit.status = BlockedStatus(str(exc))
-            return
-
-        if self.state.pod_spec != pod_spec:
-            self.model.pod.set_spec(pod_spec)
-            self.state.pod_spec = pod_spec
-
-        self.unit.status = ActiveStatus("ready")
+        container = container_builder.build()
+        # Add container to pod spec
+        pod_spec_builder.add_container(container)
+        return pod_spec_builder.build()
 
 
 if __name__ == "__main__":
diff --git a/installers/charm/mon/src/pod_spec.py b/installers/charm/mon/src/pod_spec.py
index 1c50565..dcadfc0 100644
--- a/installers/charm/mon/src/pod_spec.py
+++ b/installers/charm/mon/src/pod_spec.py
@@ -36,15 +36,18 @@
         relation_data (Dict[str, Any]): relation data.
     """
     config_validators = {
-        "openstack_default_granularity": lambda value, _: isinstance(value, int)
-        and value > 0,
+        "openstack_default_granularity": lambda value, _: (
+            isinstance(value, int) and value > 0
+        ),
         "global_request_timeout": lambda value, _: isinstance(value, int) and value > 0,
-        "log_level": lambda value, _: isinstance(value, str)
-        and value in ("INFO", "DEBUG"),
+        "log_level": lambda value, _: (
+            isinstance(value, str) and value in ("INFO", "DEBUG")
+        ),
         "collector_interval": lambda value, _: isinstance(value, int) and value > 0,
         "evaluator_interval": lambda value, _: isinstance(value, int) and value > 0,
-        "database_commonkey": lambda value, _: isinstance(value, str)
-        and len(value) > 0,
+        "database_commonkey": lambda value, _: (
+            isinstance(value, str) and len(value) > 0
+        ),
         "vca_host": lambda value, _: isinstance(value, str) and len(value) > 0,
         "vca_user": lambda value, _: isinstance(value, str) and len(value) > 0,
         "vca_password": lambda value, _: isinstance(value, str) and len(value) > 0,
@@ -53,8 +56,9 @@
     relation_validators = {
         "message_host": lambda value, _: isinstance(value, str) and len(value) > 0,
         "message_port": lambda value, _: isinstance(value, int) and value > 0,
-        "database_uri": lambda value, _: isinstance(value, str)
-        and value.startswith("mongodb://"),
+        "database_uri": lambda value, _: (
+            isinstance(value, str) and value.startswith("mongodb://")
+        ),
         "prometheus_host": lambda value, _: isinstance(value, str) and len(value) > 0,
         "prometheus_port": lambda value, _: isinstance(value, int) and value > 0,
     }
diff --git a/installers/charm/mon/tests/test_charm.py b/installers/charm/mon/tests/test_charm.py
index 010262f..6fcd6a6 100644
--- a/installers/charm/mon/tests/test_charm.py
+++ b/installers/charm/mon/tests/test_charm.py
@@ -1,5 +1,5 @@
 #!/usr/bin/env python3
-# Copyright 2020 Canonical Ltd.
+# Copyright 2021 Canonical Ltd.
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
 # not use this file except in compliance with the License. You may obtain
@@ -20,102 +20,82 @@
 # osm-charmers@lists.launchpad.net
 ##
 
+import sys
 from typing import NoReturn
 import unittest
-from ops.model import BlockedStatus
-
+from ops.model import ActiveStatus, BlockedStatus
 from ops.testing import Harness
 
 from charm import MonCharm
 
 
 class TestCharm(unittest.TestCase):
-    """MON Charm unit tests."""
+    """Prometheus Charm unit tests."""
 
     def setUp(self) -> NoReturn:
         """Test setup"""
+        self.image_info = sys.modules["oci_image"].OCIImageResource().fetch()
         self.harness = Harness(MonCharm)
         self.harness.set_leader(is_leader=True)
         self.harness.begin()
-
-    def test_on_start_without_relations(self) -> NoReturn:
-        """Test installation without any relation."""
-        self.harness.charm.on.start.emit()
-
-        # Verifying status
-        self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
-
-        # Verifying status message
-        self.assertGreater(len(self.harness.charm.unit.status.message), 0)
-        self.assertTrue(
-            self.harness.charm.unit.status.message.startswith("Waiting for ")
-        )
-        self.assertIn("kafka", self.harness.charm.unit.status.message)
-        self.assertIn("mongodb", self.harness.charm.unit.status.message)
-        self.assertIn("prometheus", self.harness.charm.unit.status.message)
-        self.assertTrue(self.harness.charm.unit.status.message.endswith(" relations"))
-
-    def test_on_start_with_relations(self) -> NoReturn:
-        """Test deployment without keystone."""
-        expected_result = {
-            "version": 3,
-            "containers": [
-                {
-                    "name": "mon",
-                    "imageDetails": self.harness.charm.image.fetch(),
-                    "imagePullPolicy": "Always",
-                    "ports": [
-                        {
-                            "name": "mon",
-                            "containerPort": 8000,
-                            "protocol": "TCP",
-                        }
-                    ],
-                    "envConfig": {
-                        "ALLOW_ANONYMOUS_LOGIN": "yes",
-                        "OSMMON_OPENSTACK_DEFAULT_GRANULARITY": 300,
-                        "OSMMON_GLOBAL_REQUEST_TIMEOUT": 10,
-                        "OSMMON_GLOBAL_LOGLEVEL": "INFO",
-                        "OSMMON_COLLECTOR_INTERVAL": 30,
-                        "OSMMON_EVALUATOR_INTERVAL": 30,
-                        "OSMMON_MESSAGE_DRIVER": "kafka",
-                        "OSMMON_MESSAGE_HOST": "kafka",
-                        "OSMMON_MESSAGE_PORT": 9092,
-                        "OSMMON_DATABASE_DRIVER": "mongo",
-                        "OSMMON_DATABASE_URI": "mongodb://mongo:27017",
-                        "OSMMON_DATABASE_COMMONKEY": "osm",
-                        "OSMMON_PROMETHEUS_URL": "http://prometheus:9090",
-                        "OSMMON_VCA_HOST": "admin",
-                        "OSMMON_VCA_USER": "admin",
-                        "OSMMON_VCA_SECRET": "secret",
-                        "OSMMON_VCA_CACERT": "",
-                    },
-                }
-            ],
-            "kubernetesResources": {"ingressResources": []},
+        self.config = {
+            "vca_host": "192.168.0.13",
+            "vca_user": "admin",
+            "vca_password": "admin",
+            "vca_cacert": "cacert",
+            "database_commonkey": "commonkey",
+            "log_level": "INFO",
+            "openstack_default_granularity": 10,
+            "global_request_timeout": 10,
+            "collector_interval": 30,
+            "evaluator_interval": 30,
         }
+        self.harness.update_config(self.config)
 
-        self.harness.charm.on.start.emit()
+    def test_config_changed_no_relations(
+        self,
+    ) -> NoReturn:
+        """Test ingress resources without HTTP."""
 
-        # Check if kafka datastore is initialized
-        self.assertIsNone(self.harness.charm.state.message_host)
-        self.assertIsNone(self.harness.charm.state.message_port)
+        self.harness.charm.on.config_changed.emit()
 
-        # Check if mongodb datastore is initialized
-        self.assertIsNone(self.harness.charm.state.database_uri)
+        # Assertions
+        self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
+        self.assertTrue(
+            all(
+                relation in self.harness.charm.unit.status.message
+                for relation in ["mongodb", "kafka", "prometheus"]
+            )
+        )
 
-        # Check if prometheus datastore is initialized
-        self.assertIsNone(self.harness.charm.state.prometheus_host)
-        self.assertIsNone(self.harness.charm.state.prometheus_port)
+    def test_config_changed_non_leader(
+        self,
+    ) -> NoReturn:
+        """Test ingress resources without HTTP."""
+        self.harness.set_leader(is_leader=False)
+        self.harness.charm.on.config_changed.emit()
 
-        # Initializing the kafka relation
+        # Assertions
+        self.assertIsInstance(self.harness.charm.unit.status, ActiveStatus)
+
+    def test_with_relations(
+        self,
+    ) -> NoReturn:
+        "Test with relations (internal)"
+        self.initialize_kafka_relation()
+        self.initialize_mongo_relation()
+        self.initialize_prometheus_relation()
+        # Verifying status
+        self.assertNotIsInstance(self.harness.charm.unit.status, BlockedStatus)
+
+    def initialize_kafka_relation(self):
         kafka_relation_id = self.harness.add_relation("kafka", "kafka")
         self.harness.add_relation_unit(kafka_relation_id, "kafka/0")
         self.harness.update_relation_data(
             kafka_relation_id, "kafka/0", {"host": "kafka", "port": 9092}
         )
 
-        # Initializing the mongo relation
+    def initialize_mongo_relation(self):
         mongodb_relation_id = self.harness.add_relation("mongodb", "mongodb")
         self.harness.add_relation_unit(mongodb_relation_id, "mongodb/0")
         self.harness.update_relation_data(
@@ -124,118 +104,227 @@
             {"connection_string": "mongodb://mongo:27017"},
         )
 
-        # Initializing the prometheus relation
+    def initialize_prometheus_relation(self):
         prometheus_relation_id = self.harness.add_relation("prometheus", "prometheus")
         self.harness.add_relation_unit(prometheus_relation_id, "prometheus/0")
         self.harness.update_relation_data(
             prometheus_relation_id,
-            "prometheus/0",
+            "prometheus",
             {"hostname": "prometheus", "port": 9090},
         )
 
-        # Checking if kafka data is stored
-        self.assertEqual(self.harness.charm.state.message_host, "kafka")
-        self.assertEqual(self.harness.charm.state.message_port, 9092)
-
-        # Checking if mongodb data is stored
-        self.assertEqual(self.harness.charm.state.database_uri, "mongodb://mongo:27017")
-
-        # Checking if prometheus data is stored
-        self.assertEqual(self.harness.charm.state.prometheus_host, "prometheus")
-        self.assertEqual(self.harness.charm.state.prometheus_port, 9090)
-
-        # Verifying status
-        self.assertNotIsInstance(self.harness.charm.unit.status, BlockedStatus)
-
-        pod_spec, _ = self.harness.get_pod_spec()
-
-        self.assertDictEqual(expected_result, pod_spec)
-
-    def test_on_kafka_unit_relation_changed(self) -> NoReturn:
-        """Test to see if kafka relation is updated."""
-        self.harness.charm.on.start.emit()
-
-        self.assertIsNone(self.harness.charm.state.message_host)
-        self.assertIsNone(self.harness.charm.state.message_port)
-
-        relation_id = self.harness.add_relation("kafka", "kafka")
-        self.harness.add_relation_unit(relation_id, "kafka/0")
-        self.harness.update_relation_data(
-            relation_id, "kafka/0", {"host": "kafka", "port": 9092}
-        )
-
-        self.assertEqual(self.harness.charm.state.message_host, "kafka")
-        self.assertEqual(self.harness.charm.state.message_port, 9092)
-
-        # Verifying status
-        self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
-
-        # Verifying status message
-        self.assertGreater(len(self.harness.charm.unit.status.message), 0)
-        self.assertTrue(
-            self.harness.charm.unit.status.message.startswith("Waiting for ")
-        )
-        self.assertNotIn("kafka", self.harness.charm.unit.status.message)
-        self.assertIn("mongodb", self.harness.charm.unit.status.message)
-        self.assertIn("prometheus", self.harness.charm.unit.status.message)
-        self.assertTrue(self.harness.charm.unit.status.message.endswith(" relations"))
-
-    def test_on_mongodb_unit_relation_changed(self) -> NoReturn:
-        """Test to see if mongodb relation is updated."""
-        self.harness.charm.on.start.emit()
-
-        self.assertIsNone(self.harness.charm.state.database_uri)
-
-        relation_id = self.harness.add_relation("mongodb", "mongodb")
-        self.harness.add_relation_unit(relation_id, "mongodb/0")
-        self.harness.update_relation_data(
-            relation_id, "mongodb/0", {"connection_string": "mongodb://mongo:27017"}
-        )
-
-        self.assertEqual(self.harness.charm.state.database_uri, "mongodb://mongo:27017")
-
-        # Verifying status
-        self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
-
-        # Verifying status message
-        self.assertGreater(len(self.harness.charm.unit.status.message), 0)
-        self.assertTrue(
-            self.harness.charm.unit.status.message.startswith("Waiting for ")
-        )
-        self.assertIn("kafka", self.harness.charm.unit.status.message)
-        self.assertNotIn("mongodb", self.harness.charm.unit.status.message)
-        self.assertIn("prometheus", self.harness.charm.unit.status.message)
-        self.assertTrue(self.harness.charm.unit.status.message.endswith(" relations"))
-
-    def test_on_prometheus_unit_relation_changed(self) -> NoReturn:
-        """Test to see if prometheus relation is updated."""
-        self.harness.charm.on.start.emit()
-
-        self.assertIsNone(self.harness.charm.state.prometheus_host)
-        self.assertIsNone(self.harness.charm.state.prometheus_port)
-
-        relation_id = self.harness.add_relation("prometheus", "prometheus")
-        self.harness.add_relation_unit(relation_id, "prometheus/0")
-        self.harness.update_relation_data(
-            relation_id, "prometheus/0", {"hostname": "prometheus", "port": 9090}
-        )
-
-        self.assertEqual(self.harness.charm.state.prometheus_host, "prometheus")
-        self.assertEqual(self.harness.charm.state.prometheus_port, 9090)
-
-        # Verifying status
-        self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
-
-        # Verifying status message
-        self.assertGreater(len(self.harness.charm.unit.status.message), 0)
-        self.assertTrue(
-            self.harness.charm.unit.status.message.startswith("Waiting for ")
-        )
-        self.assertIn("kafka", self.harness.charm.unit.status.message)
-        self.assertIn("mongodb", self.harness.charm.unit.status.message)
-        self.assertNotIn("prometheus", self.harness.charm.unit.status.message)
-        self.assertTrue(self.harness.charm.unit.status.message.endswith(" relations"))
-
 
 if __name__ == "__main__":
     unittest.main()
+
+
+# class TestCharm(unittest.TestCase):
+#     """MON Charm unit tests."""
+
+#     def setUp(self) -> NoReturn:
+#         """Test setup"""
+#         self.harness = Harness(MonCharm)
+#         self.harness.set_leader(is_leader=True)
+#         self.harness.begin()
+
+#     def test_on_start_without_relations(self) -> NoReturn:
+#         """Test installation without any relation."""
+#         self.harness.charm.on.start.emit()
+
+#         # Verifying status
+#         self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
+
+#         # Verifying status message
+#         self.assertGreater(len(self.harness.charm.unit.status.message), 0)
+#         self.assertTrue(
+#             self.harness.charm.unit.status.message.startswith("Waiting for ")
+#         )
+#         self.assertIn("kafka", self.harness.charm.unit.status.message)
+#         self.assertIn("mongodb", self.harness.charm.unit.status.message)
+#         self.assertIn("prometheus", self.harness.charm.unit.status.message)
+#         self.assertTrue(self.harness.charm.unit.status.message.endswith(" relations"))
+
+#     def test_on_start_with_relations(self) -> NoReturn:
+#         """Test deployment without keystone."""
+#         expected_result = {
+#             "version": 3,
+#             "containers": [
+#                 {
+#                     "name": "mon",
+#                     "imageDetails": self.harness.charm.image.fetch(),
+#                     "imagePullPolicy": "Always",
+#                     "ports": [
+#                         {
+#                             "name": "mon",
+#                             "containerPort": 8000,
+#                             "protocol": "TCP",
+#                         }
+#                     ],
+#                     "envConfig": {
+#                         "ALLOW_ANONYMOUS_LOGIN": "yes",
+#                         "OSMMON_OPENSTACK_DEFAULT_GRANULARITY": 300,
+#                         "OSMMON_GLOBAL_REQUEST_TIMEOUT": 10,
+#                         "OSMMON_GLOBAL_LOGLEVEL": "INFO",
+#                         "OSMMON_COLLECTOR_INTERVAL": 30,
+#                         "OSMMON_EVALUATOR_INTERVAL": 30,
+#                         "OSMMON_MESSAGE_DRIVER": "kafka",
+#                         "OSMMON_MESSAGE_HOST": "kafka",
+#                         "OSMMON_MESSAGE_PORT": 9092,
+#                         "OSMMON_DATABASE_DRIVER": "mongo",
+#                         "OSMMON_DATABASE_URI": "mongodb://mongo:27017",
+#                         "OSMMON_DATABASE_COMMONKEY": "osm",
+#                         "OSMMON_PROMETHEUS_URL": "http://prometheus:9090",
+#                         "OSMMON_VCA_HOST": "admin",
+#                         "OSMMON_VCA_USER": "admin",
+#                         "OSMMON_VCA_SECRET": "secret",
+#                         "OSMMON_VCA_CACERT": "",
+#                     },
+#                 }
+#             ],
+#             "kubernetesResources": {"ingressResources": []},
+#         }
+
+#         self.harness.charm.on.start.emit()
+
+#         # Check if kafka datastore is initialized
+#         self.assertIsNone(self.harness.charm.state.message_host)
+#         self.assertIsNone(self.harness.charm.state.message_port)
+
+#         # Check if mongodb datastore is initialized
+#         self.assertIsNone(self.harness.charm.state.database_uri)
+
+#         # Check if prometheus datastore is initialized
+#         self.assertIsNone(self.harness.charm.state.prometheus_host)
+#         self.assertIsNone(self.harness.charm.state.prometheus_port)
+
+#         # Initializing the kafka relation
+#         kafka_relation_id = self.harness.add_relation("kafka", "kafka")
+#         self.harness.add_relation_unit(kafka_relation_id, "kafka/0")
+#         self.harness.update_relation_data(
+#             kafka_relation_id, "kafka/0", {"host": "kafka", "port": 9092}
+#         )
+
+#         # Initializing the mongo relation
+#         mongodb_relation_id = self.harness.add_relation("mongodb", "mongodb")
+#         self.harness.add_relation_unit(mongodb_relation_id, "mongodb/0")
+#         self.harness.update_relation_data(
+#             mongodb_relation_id,
+#             "mongodb/0",
+#             {"connection_string": "mongodb://mongo:27017"},
+#         )
+
+#         # Initializing the prometheus relation
+#         prometheus_relation_id = self.harness.add_relation("prometheus", "prometheus")
+#         self.harness.add_relation_unit(prometheus_relation_id, "prometheus/0")
+#         self.harness.update_relation_data(
+#             prometheus_relation_id,
+#             "prometheus",
+#             {"hostname": "prometheus", "port": 9090},
+#         )
+
+#         # Checking if kafka data is stored
+#         self.assertEqual(self.harness.charm.state.message_host, "kafka")
+#         self.assertEqual(self.harness.charm.state.message_port, 9092)
+
+#         # Checking if mongodb data is stored
+#         self.assertEqual(self.harness.charm.state.database_uri, "mongodb://mongo:27017")
+
+#         # Checking if prometheus data is stored
+#         self.assertEqual(self.harness.charm.state.prometheus_host, "prometheus")
+#         self.assertEqual(self.harness.charm.state.prometheus_port, 9090)
+
+#         # Verifying status
+#         self.assertNotIsInstance(self.harness.charm.unit.status, BlockedStatus)
+
+#         pod_spec, _ = self.harness.get_pod_spec()
+
+#         self.assertDictEqual(expected_result, pod_spec)
+
+#     def test_on_kafka_unit_relation_changed(self) -> NoReturn:
+#         """Test to see if kafka relation is updated."""
+#         self.harness.charm.on.start.emit()
+
+#         self.assertIsNone(self.harness.charm.state.message_host)
+#         self.assertIsNone(self.harness.charm.state.message_port)
+
+#         relation_id = self.harness.add_relation("kafka", "kafka")
+#         self.harness.add_relation_unit(relation_id, "kafka/0")
+#         self.harness.update_relation_data(
+#             relation_id, "kafka/0", {"host": "kafka", "port": 9092}
+#         )
+
+#         self.assertEqual(self.harness.charm.state.message_host, "kafka")
+#         self.assertEqual(self.harness.charm.state.message_port, 9092)
+
+#         # Verifying status
+#         self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
+
+#         # Verifying status message
+#         self.assertGreater(len(self.harness.charm.unit.status.message), 0)
+#         self.assertTrue(
+#             self.harness.charm.unit.status.message.startswith("Waiting for ")
+#         )
+#         self.assertNotIn("kafka", self.harness.charm.unit.status.message)
+#         self.assertIn("mongodb", self.harness.charm.unit.status.message)
+#         self.assertIn("prometheus", self.harness.charm.unit.status.message)
+#         self.assertTrue(self.harness.charm.unit.status.message.endswith(" relations"))
+
+#     def test_on_mongodb_unit_relation_changed(self) -> NoReturn:
+#         """Test to see if mongodb relation is updated."""
+#         self.harness.charm.on.start.emit()
+
+#         self.assertIsNone(self.harness.charm.state.database_uri)
+
+#         relation_id = self.harness.add_relation("mongodb", "mongodb")
+#         self.harness.add_relation_unit(relation_id, "mongodb/0")
+#         self.harness.update_relation_data(
+#             relation_id, "mongodb/0", {"connection_string": "mongodb://mongo:27017"}
+#         )
+
+#         self.assertEqual(self.harness.charm.state.database_uri, "mongodb://mongo:27017")
+
+#         # Verifying status
+#         self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
+
+#         # Verifying status message
+#         self.assertGreater(len(self.harness.charm.unit.status.message), 0)
+#         self.assertTrue(
+#             self.harness.charm.unit.status.message.startswith("Waiting for ")
+#         )
+#         self.assertIn("kafka", self.harness.charm.unit.status.message)
+#         self.assertNotIn("mongodb", self.harness.charm.unit.status.message)
+#         self.assertIn("prometheus", self.harness.charm.unit.status.message)
+#         self.assertTrue(self.harness.charm.unit.status.message.endswith(" relations"))
+
+#     def test_on_prometheus_unit_relation_changed(self) -> NoReturn:
+#         """Test to see if prometheus relation is updated."""
+#         self.harness.charm.on.start.emit()
+
+#         self.assertIsNone(self.harness.charm.state.prometheus_host)
+#         self.assertIsNone(self.harness.charm.state.prometheus_port)
+
+#         relation_id = self.harness.add_relation("prometheus", "prometheus")
+#         self.harness.add_relation_unit(relation_id, "prometheus/0")
+#         self.harness.update_relation_data(
+#             relation_id, "prometheus", {"hostname": "prometheus", "port": 9090}
+#         )
+
+#         self.assertEqual(self.harness.charm.state.prometheus_host, "prometheus")
+#         self.assertEqual(self.harness.charm.state.prometheus_port, 9090)
+
+#         # Verifying status
+#         self.assertIsInstance(self.harness.charm.unit.status, BlockedStatus)
+
+#         # Verifying status message
+#         self.assertGreater(len(self.harness.charm.unit.status.message), 0)
+#         self.assertTrue(
+#             self.harness.charm.unit.status.message.startswith("Waiting for ")
+#         )
+#         self.assertIn("kafka", self.harness.charm.unit.status.message)
+#         self.assertIn("mongodb", self.harness.charm.unit.status.message)
+#         self.assertNotIn("prometheus", self.harness.charm.unit.status.message)
+#         self.assertTrue(self.harness.charm.unit.status.message.endswith(" relations"))
+
+
+# if __name__ == "__main__":
+#     unittest.main()
diff --git a/installers/charm/mon/tests/test_pod_spec.py b/installers/charm/mon/tests/test_pod_spec.py
index 777c18e..6f61916 100644
--- a/installers/charm/mon/tests/test_pod_spec.py
+++ b/installers/charm/mon/tests/test_pod_spec.py
@@ -199,7 +199,8 @@
                         "OSMMON_DATABASE_DRIVER": "mongo",
                         "OSMMON_DATABASE_URI": relation_state["database_uri"],
                         "OSMMON_DATABASE_COMMONKEY": config["database_commonkey"],
-                        "OSMMON_PROMETHEUS_URL": f"http://{relation_state['prometheus_host']}:{relation_state['prometheus_port']}",
+                        "OSMMON_PROMETHEUS_URL": 
+                            f"http://{relation_state['prometheus_host']}:{relation_state['prometheus_port']}",
                         "OSMMON_VCA_HOST": config["vca_host"],
                         "OSMMON_VCA_USER": config["vca_user"],
                         "OSMMON_VCA_SECRET": config["vca_password"],
diff --git a/installers/charm/mon/tox.ini b/installers/charm/mon/tox.ini
index 7ddaf8d..1f9442e 100644
--- a/installers/charm/mon/tox.ini
+++ b/installers/charm/mon/tox.ini
@@ -1,4 +1,4 @@
-# Copyright 2020 Canonical Ltd.
+# Copyright 2021 Canonical Ltd.
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may
 # not use this file except in compliance with the License. You may obtain
@@ -18,63 +18,98 @@
 # To get in touch with the maintainers, please contact:
 # osm-charmers@lists.launchpad.net
 ##
+#######################################################################################
 
 [tox]
+envlist = flake8, cover, pylint, safety, yamllint
 skipsdist = True
-envlist = unit, lint
-sitepackages = False
-skip_missing_interpreters = False
 
 [testenv]
 basepython = python3.8
 setenv =
+  VIRTUAL_ENV={envdir}
   PYTHONHASHSEED=0
   PYTHONPATH = {toxinidir}/src
-  CHARM_NAME = mon
+deps =  -r{toxinidir}/requirements.txt
 
+#######################################################################################
+[testenv:cover]
+deps =  {[testenv]deps}
+        -r{toxinidir}/requirements-test.txt
+commands =
+        sh -c 'rm -f nosetests.xml'
+        coverage erase
+        nose2 -C --coverage src
+        coverage report --omit='*tests*'
+        coverage html -d ./cover --omit='*tests*'
+        coverage xml -o coverage.xml --omit=*tests*
+whitelist_externals = sh
+
+#######################################################################################
+[testenv:safety]
+setenv =
+        LC_ALL=C.UTF-8
+        LANG=C.UTF-8
+deps =  {[testenv]deps}
+        -r{toxinidir}/requirements-test.txt
+commands =
+        - safety check --full-report
+
+#######################################################################################
+[testenv:flake8]
+deps = flake8
+commands =
+        flake8 src/ tests/
+
+#######################################################################################
+[testenv:pylint]
+deps =  {[testenv]deps}
+        -r{toxinidir}/requirements-test.txt
+        pylint
+commands =
+    pylint -E src
+
+#######################################################################################
+[testenv:black]
+deps =  {[testenv]deps}
+        -r{toxinidir}/requirements-test.txt
+        black
+commands =  black --check --diff . --exclude "build/|.tox/|mod/|lib/"
+
+#######################################################################################
+[testenv:yamllint]
+deps =  {[testenv]deps}
+        -r{toxinidir}/requirements-test.txt
+        yamllint
+commands = yamllint .
+
+#######################################################################################
 [testenv:build]
 passenv=HTTP_PROXY HTTPS_PROXY NO_PROXY
+deps =  {[testenv]deps}
+        -r{toxinidir}/requirements-test.txt
+        charmcraft
 whitelist_externals =
   charmcraft
-  rm
-  unzip
+  cp
 commands =
-  rm -rf release mon.charm
   charmcraft build
-  unzip mon.charm -d release
+  cp -r build release
 
-[testenv:unit]
-commands =
-  coverage erase
-  stestr run --slowest --test-path=./tests --top-dir=./
-  coverage combine
-  coverage html -d cover
-  coverage xml -o cover/coverage.xml
-  coverage report
-deps =
-  coverage
-  stestr
-  mock
-  ops
-setenv =
-  {[testenv]setenv}
-  PYTHON=coverage run
+#######################################################################################
+[flake8]
+ignore =
+        W291,
+        W293,
+        E123,
+        E125,
+        E226,
+        E241,
+exclude =
+        .git,
+        __pycache__,
+        .tox,
+max-line-length = 120
+show-source = True
+builtins = _
 
-[testenv:lint]
-deps =
-  black
-  yamllint
-  flake8
-commands =
-  black --check --diff . --exclude "build/|.tox/|mod/|lib/|release/"
-  yamllint .
-  flake8 . --max-line-length=100 --ignore="E501,W503,W504,F722" --exclude "build/ .tox/ mod/ lib/ release/"
-[coverage:run]
-branch = True
-concurrency = multiprocessing
-parallel = True
-source =
-  .
-omit =  
-  .tox/*
-  tests/*