Revert "Feature 11071: Modular OSM installation. Remove charms, juju and lxd"

This reverts commit a0f0d8ef4f2aa0dd227ecb651002490b66498bab.

Change-Id: I92394e4074dad4e457c107c58e4ebc17d507f8b2
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/installers/charm/osm-mon/src/charm.py b/installers/charm/osm-mon/src/charm.py
new file mode 100755
index 0000000..12c5dcd
--- /dev/null
+++ b/installers/charm/osm-mon/src/charm.py
@@ -0,0 +1,300 @@
+#!/usr/bin/env python3
+# Copyright 2022 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
+#
+#
+# Learn more at: https://juju.is/docs/sdk
+
+"""OSM MON charm.
+
+See more: https://charmhub.io/osm
+"""
+
+import logging
+from typing import Any, Dict
+
+from charms.data_platform_libs.v0.data_interfaces import DatabaseRequires
+from charms.kafka_k8s.v0.kafka import KafkaRequires, _KafkaAvailableEvent
+from charms.observability_libs.v1.kubernetes_service_patch import KubernetesServicePatch
+from charms.osm_libs.v0.utils import (
+    CharmError,
+    DebugMode,
+    HostPath,
+    check_container_ready,
+    check_service_active,
+)
+from charms.osm_vca_integrator.v0.vca import VcaDataChangedEvent, VcaRequires
+from lightkube.models.core_v1 import ServicePort
+from ops.charm import ActionEvent, CharmBase, CharmEvents
+from ops.framework import EventSource, StoredState
+from ops.main import main
+from ops.model import ActiveStatus, Container
+
+from legacy_interfaces import KeystoneClient, PrometheusClient
+
+HOSTPATHS = [
+    HostPath(
+        config="mon-hostpath",
+        container_path="/usr/lib/python3/dist-packages/osm_mon",
+    ),
+    HostPath(
+        config="common-hostpath",
+        container_path="/usr/lib/python3/dist-packages/osm_common",
+    ),
+    HostPath(
+        config="n2vc-hostpath",
+        container_path="/usr/lib/python3/dist-packages/n2vc",
+    ),
+]
+SERVICE_PORT = 8000
+
+logger = logging.getLogger(__name__)
+
+
+class MonEvents(CharmEvents):
+    """MON events."""
+
+    vca_data_changed = EventSource(VcaDataChangedEvent)
+    kafka_available = EventSource(_KafkaAvailableEvent)
+
+
+class OsmMonCharm(CharmBase):
+    """OSM MON Kubernetes sidecar charm."""
+
+    on = MonEvents()
+    _stored = StoredState()
+    container_name = "mon"
+    service_name = "mon"
+
+    def __init__(self, *args):
+        super().__init__(*args)
+        self.kafka = KafkaRequires(self)
+        self.mongodb_client = DatabaseRequires(self, "mongodb", database_name="osm")
+        self.prometheus_client = PrometheusClient(self, "prometheus")
+        self.keystone_client = KeystoneClient(self, "keystone")
+        self.vca = VcaRequires(self)
+        self._observe_charm_events()
+        self.container: Container = self.unit.get_container(self.container_name)
+        self.debug_mode = DebugMode(self, self._stored, self.container, HOSTPATHS)
+        self._patch_k8s_service()
+
+    @property
+    def external_hostname(self) -> str:
+        """External hostname property.
+
+        Returns:
+            str: the external hostname from config.
+                If not set, return the ClusterIP service name.
+        """
+        return self.config.get("external-hostname") or self.app.name
+
+    # ---------------------------------------------------------------------------
+    #   Handlers for Charm Events
+    # ---------------------------------------------------------------------------
+
+    def _on_config_changed(self, _) -> None:
+        """Handler for the config-changed event."""
+        try:
+            self._validate_config()
+            self._check_relations()
+            # Check if the container is ready.
+            # Eventually it will become ready after the first pebble-ready event.
+            check_container_ready(self.container)
+            if not self.debug_mode.started:
+                self._configure_service(self.container)
+            # Update charm status
+            self._on_update_status()
+        except CharmError as e:
+            logger.debug(e.message)
+            self.unit.status = e.status
+
+    def _on_update_status(self, _=None) -> None:
+        """Handler for the update-status event."""
+        try:
+            self._validate_config()
+            self._check_relations()
+            check_container_ready(self.container)
+            if self.debug_mode.started:
+                return
+            check_service_active(self.container, self.service_name)
+            self.unit.status = ActiveStatus()
+        except CharmError as e:
+            logger.debug(e.message)
+            self.unit.status = e.status
+
+    def _on_required_relation_broken(self, _) -> None:
+        """Handler for the kafka-broken event."""
+        try:
+            check_container_ready(self.container)
+            check_service_active(self.container, self.service_name)
+            self.container.stop(self.container_name)
+        except CharmError:
+            pass
+        self._on_update_status()
+
+    def _on_get_debug_mode_information_action(self, event: ActionEvent) -> None:
+        """Handler for the get-debug-mode-information action event."""
+        if not self.debug_mode.started:
+            event.fail("debug-mode has not started. Hint: juju config mon debug-mode=true")
+            return
+
+        debug_info = {
+            "command": self.debug_mode.command,
+            "password": self.debug_mode.password,
+        }
+        event.set_results(debug_info)
+
+    # ---------------------------------------------------------------------------
+    #   Validation and configuration and more
+    # ---------------------------------------------------------------------------
+
+    def _observe_charm_events(self) -> None:
+        event_handler_mapping = {
+            # Core lifecycle events
+            self.on.mon_pebble_ready: self._on_config_changed,
+            self.on.config_changed: self._on_config_changed,
+            self.on.update_status: self._on_update_status,
+            # Relation events
+            self.on.vca_data_changed: self._on_config_changed,
+            self.on.kafka_available: self._on_config_changed,
+            self.on["kafka"].relation_broken: self._on_required_relation_broken,
+            self.mongodb_client.on.database_created: self._on_config_changed,
+            self.on["mongodb"].relation_broken: self._on_required_relation_broken,
+            # Action events
+            self.on.get_debug_mode_information_action: self._on_get_debug_mode_information_action,
+        }
+        for relation in [self.on[rel_name] for rel_name in ["prometheus", "keystone"]]:
+            event_handler_mapping[relation.relation_changed] = self._on_config_changed
+            event_handler_mapping[relation.relation_broken] = self._on_required_relation_broken
+
+        for event, handler in event_handler_mapping.items():
+            self.framework.observe(event, handler)
+
+    def _is_database_available(self) -> bool:
+        try:
+            return self.mongodb_client.is_resource_created()
+        except KeyError:
+            return False
+
+    def _validate_config(self) -> None:
+        """Validate charm configuration.
+
+        Raises:
+            CharmError: if charm configuration is invalid.
+        """
+        logger.debug("validating charm config")
+
+    def _check_relations(self) -> None:
+        """Validate charm relations.
+
+        Raises:
+            CharmError: if charm configuration is invalid.
+        """
+        logger.debug("check for missing relations")
+        missing_relations = []
+
+        if not self.kafka.host or not self.kafka.port:
+            missing_relations.append("kafka")
+        if not self._is_database_available():
+            missing_relations.append("mongodb")
+        if self.prometheus_client.is_missing_data_in_app():
+            missing_relations.append("prometheus")
+        if self.keystone_client.is_missing_data_in_app():
+            missing_relations.append("keystone")
+
+        if missing_relations:
+            relations_str = ", ".join(missing_relations)
+            one_relation_missing = len(missing_relations) == 1
+            error_msg = f'need {relations_str} relation{"" if one_relation_missing else "s"}'
+            logger.warning(error_msg)
+            raise CharmError(error_msg)
+
+    def _configure_service(self, container: Container) -> None:
+        """Add Pebble layer with the mon service."""
+        logger.debug(f"configuring {self.app.name} service")
+        container.add_layer("mon", self._get_layer(), combine=True)
+        container.replan()
+
+    def _get_layer(self) -> Dict[str, Any]:
+        """Get layer for Pebble."""
+        environment = {
+            # General configuration
+            "OSMMON_GLOBAL_LOGLEVEL": self.config["log-level"],
+            "OSMMON_OPENSTACK_DEFAULT_GRANULARITY": self.config["openstack-default-granularity"],
+            "OSMMON_GLOBAL_REQUEST_TIMEOUT": self.config["global-request-timeout"],
+            "OSMMON_COLLECTOR_INTERVAL": self.config["collector-interval"],
+            "OSMMON_EVALUATOR_INTERVAL": self.config["evaluator-interval"],
+            "OSMMON_COLLECTOR_VM_INFRA_METRICS": self.config["vm-infra-metrics"],
+            # Kafka configuration
+            "OSMMON_MESSAGE_DRIVER": "kafka",
+            "OSMMON_MESSAGE_HOST": self.kafka.host,
+            "OSMMON_MESSAGE_PORT": self.kafka.port,
+            # Database configuration
+            "OSMMON_DATABASE_DRIVER": "mongo",
+            "OSMMON_DATABASE_URI": self._get_mongodb_uri(),
+            "OSMMON_DATABASE_COMMONKEY": self.config["database-commonkey"],
+            # Prometheus/grafana configuration
+            "OSMMON_PROMETHEUS_URL": f"http://{self.prometheus_client.hostname}:{self.prometheus_client.port}",
+            "OSMMON_PROMETHEUS_USER": self.prometheus_client.user,
+            "OSMMON_PROMETHEUS_PASSWORD": self.prometheus_client.password,
+            "OSMMON_GRAFANA_URL": self.config["grafana-url"],
+            "OSMMON_GRAFANA_USER": self.config["grafana-user"],
+            "OSMMON_GRAFANA_PASSWORD": self.config["grafana-password"],
+            "OSMMON_KEYSTONE_ENABLED": self.config["keystone-enabled"],
+            "OSMMON_KEYSTONE_URL": self.keystone_client.host,
+            "OSMMON_KEYSTONE_DOMAIN_NAME": self.keystone_client.user_domain_name,
+            "OSMMON_KEYSTONE_SERVICE_PROJECT": self.keystone_client.service,
+            "OSMMON_KEYSTONE_SERVICE_USER": self.keystone_client.username,
+            "OSMMON_KEYSTONE_SERVICE_PASSWORD": self.keystone_client.password,
+            "OSMMON_KEYSTONE_SERVICE_PROJECT_DOMAIN_NAME": self.keystone_client.project_domain_name,
+        }
+        logger.info(f"{environment}")
+        if self.vca.data:
+            environment["OSMMON_VCA_HOST"] = self.vca.data.endpoints
+            environment["OSMMON_VCA_SECRET"] = self.vca.data.secret
+            environment["OSMMON_VCA_USER"] = self.vca.data.user
+            environment["OSMMON_VCA_CACERT"] = self.vca.data.cacert
+        return {
+            "summary": "mon layer",
+            "description": "pebble config layer for mon",
+            "services": {
+                self.service_name: {
+                    "override": "replace",
+                    "summary": "mon service",
+                    "command": "/bin/bash -c 'cd /app/osm_mon/ && /bin/bash start.sh'",
+                    "startup": "enabled",
+                    "user": "appuser",
+                    "group": "appuser",
+                    "working-dir": "/app/osm_mon",  # This parameter has no effect in Juju 2.9.x
+                    "environment": environment,
+                }
+            },
+        }
+
+    def _get_mongodb_uri(self):
+        return list(self.mongodb_client.fetch_relation_data().values())[0]["uris"]
+
+    def _patch_k8s_service(self) -> None:
+        port = ServicePort(SERVICE_PORT, name=f"{self.app.name}")
+        self.service_patcher = KubernetesServicePatch(self, [port])
+
+
+if __name__ == "__main__":  # pragma: no cover
+    main(OsmMonCharm)
diff --git a/installers/charm/osm-mon/src/legacy_interfaces.py b/installers/charm/osm-mon/src/legacy_interfaces.py
new file mode 100644
index 0000000..5deb3f5
--- /dev/null
+++ b/installers/charm/osm-mon/src/legacy_interfaces.py
@@ -0,0 +1,205 @@
+#!/usr/bin/env python3
+# Copyright 2022 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
+#
+# flake8: noqa
+
+import ops
+
+
+class BaseRelationClient(ops.framework.Object):
+    """Requires side of a Kafka Endpoint"""
+
+    def __init__(
+        self,
+        charm: ops.charm.CharmBase,
+        relation_name: str,
+        mandatory_fields: list = [],
+    ):
+        super().__init__(charm, relation_name)
+        self.relation_name = relation_name
+        self.mandatory_fields = mandatory_fields
+        self._update_relation()
+
+    def get_data_from_unit(self, key: str):
+        if not self.relation:
+            # This update relation doesn't seem to be needed, but I added it because apparently
+            # the data is empty in the unit tests.
+            # In reality, the constructor is called in every hook.
+            # In the unit tests when doing an update_relation_data, apparently it is not called.
+            self._update_relation()
+        if self.relation:
+            for unit in self.relation.units:
+                data = self.relation.data[unit].get(key)
+                if data:
+                    return data
+
+    def get_data_from_app(self, key: str):
+        if not self.relation or self.relation.app not in self.relation.data:
+            # This update relation doesn't seem to be needed, but I added it because apparently
+            # the data is empty in the unit tests.
+            # In reality, the constructor is called in every hook.
+            # In the unit tests when doing an update_relation_data, apparently it is not called.
+            self._update_relation()
+        if self.relation and self.relation.app in self.relation.data:
+            data = self.relation.data[self.relation.app].get(key)
+            if data:
+                return data
+
+    def is_missing_data_in_unit(self):
+        return not all([self.get_data_from_unit(field) for field in self.mandatory_fields])
+
+    def is_missing_data_in_app(self):
+        return not all([self.get_data_from_app(field) for field in self.mandatory_fields])
+
+    def _update_relation(self):
+        self.relation = self.framework.model.get_relation(self.relation_name)
+
+
+class KeystoneClient(BaseRelationClient):
+    """Requires side of a Keystone Endpoint"""
+
+    mandatory_fields = [
+        "host",
+        "port",
+        "user_domain_name",
+        "project_domain_name",
+        "username",
+        "password",
+        "service",
+        "keystone_db_password",
+        "region_id",
+        "admin_username",
+        "admin_password",
+        "admin_project_name",
+    ]
+
+    def __init__(self, charm: ops.charm.CharmBase, relation_name: str):
+        super().__init__(charm, relation_name, self.mandatory_fields)
+
+    @property
+    def host(self):
+        return self.get_data_from_app("host")
+
+    @property
+    def port(self):
+        return self.get_data_from_app("port")
+
+    @property
+    def user_domain_name(self):
+        return self.get_data_from_app("user_domain_name")
+
+    @property
+    def project_domain_name(self):
+        return self.get_data_from_app("project_domain_name")
+
+    @property
+    def username(self):
+        return self.get_data_from_app("username")
+
+    @property
+    def password(self):
+        return self.get_data_from_app("password")
+
+    @property
+    def service(self):
+        return self.get_data_from_app("service")
+
+    @property
+    def keystone_db_password(self):
+        return self.get_data_from_app("keystone_db_password")
+
+    @property
+    def region_id(self):
+        return self.get_data_from_app("region_id")
+
+    @property
+    def admin_username(self):
+        return self.get_data_from_app("admin_username")
+
+    @property
+    def admin_password(self):
+        return self.get_data_from_app("admin_password")
+
+    @property
+    def admin_project_name(self):
+        return self.get_data_from_app("admin_project_name")
+
+
+class MongoClient(BaseRelationClient):
+    """Requires side of a Mongo Endpoint"""
+
+    mandatory_fields_mapping = {
+        "reactive": ["connection_string"],
+        "ops": ["replica_set_uri", "replica_set_name"],
+    }
+
+    def __init__(self, charm: ops.charm.CharmBase, relation_name: str):
+        super().__init__(charm, relation_name, mandatory_fields=[])
+
+    @property
+    def connection_string(self):
+        if self.is_opts():
+            replica_set_uri = self.get_data_from_unit("replica_set_uri")
+            replica_set_name = self.get_data_from_unit("replica_set_name")
+            return f"{replica_set_uri}?replicaSet={replica_set_name}"
+        else:
+            return self.get_data_from_unit("connection_string")
+
+    def is_opts(self):
+        return not self.is_missing_data_in_unit_ops()
+
+    def is_missing_data_in_unit(self):
+        return self.is_missing_data_in_unit_ops() and self.is_missing_data_in_unit_reactive()
+
+    def is_missing_data_in_unit_ops(self):
+        return not all(
+            [self.get_data_from_unit(field) for field in self.mandatory_fields_mapping["ops"]]
+        )
+
+    def is_missing_data_in_unit_reactive(self):
+        return not all(
+            [self.get_data_from_unit(field) for field in self.mandatory_fields_mapping["reactive"]]
+        )
+
+
+class PrometheusClient(BaseRelationClient):
+    """Requires side of a Prometheus Endpoint"""
+
+    mandatory_fields = ["hostname", "port"]
+
+    def __init__(self, charm: ops.charm.CharmBase, relation_name: str):
+        super().__init__(charm, relation_name, self.mandatory_fields)
+
+    @property
+    def hostname(self):
+        return self.get_data_from_app("hostname")
+
+    @property
+    def port(self):
+        return self.get_data_from_app("port")
+
+    @property
+    def user(self):
+        return self.get_data_from_app("user")
+
+    @property
+    def password(self):
+        return self.get_data_from_app("password")