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/prometheus/src/charm.py b/installers/charm/prometheus/src/charm.py
new file mode 100755
index 0000000..af39a13
--- /dev/null
+++ b/installers/charm/prometheus/src/charm.py
@@ -0,0 +1,298 @@
+#!/usr/bin/env python3
+# 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
+##
+
+# pylint: disable=E0213
+
+import base64
+from ipaddress import ip_network
+import logging
+from typing import NoReturn, Optional
+from urllib.parse import urlparse
+
+import bcrypt
+from oci_image import OCIImageResource
+from ops.framework import EventBase
+from ops.main import main
+from opslib.osm.charm import CharmedOsmBase
+from opslib.osm.interfaces.prometheus import PrometheusServer
+from opslib.osm.pod import (
+    ContainerV3Builder,
+    FilesV3Builder,
+    IngressResourceV3Builder,
+    PodSpecV3Builder,
+)
+from opslib.osm.validator import (
+    ModelValidator,
+    validator,
+)
+import requests
+
+
+logger = logging.getLogger(__name__)
+
+PORT = 9090
+
+
+class ConfigModel(ModelValidator):
+    web_subpath: str
+    default_target: str
+    max_file_size: int
+    site_url: Optional[str]
+    cluster_issuer: Optional[str]
+    ingress_class: Optional[str]
+    ingress_whitelist_source_range: Optional[str]
+    tls_secret_name: Optional[str]
+    enable_web_admin_api: bool
+    image_pull_policy: str
+    security_context: bool
+    web_config_username: str
+    web_config_password: str
+
+    @validator("web_subpath")
+    def validate_web_subpath(cls, v):
+        if len(v) < 1:
+            raise ValueError("web-subpath must be a non-empty string")
+        return v
+
+    @validator("max_file_size")
+    def validate_max_file_size(cls, v):
+        if v < 0:
+            raise ValueError("value must be equal or greater than 0")
+        return v
+
+    @validator("site_url")
+    def validate_site_url(cls, v):
+        if v:
+            parsed = urlparse(v)
+            if not parsed.scheme.startswith("http"):
+                raise ValueError("value must start with http")
+        return v
+
+    @validator("ingress_whitelist_source_range")
+    def validate_ingress_whitelist_source_range(cls, v):
+        if v:
+            ip_network(v)
+        return v
+
+    @validator("image_pull_policy")
+    def validate_image_pull_policy(cls, v):
+        values = {
+            "always": "Always",
+            "ifnotpresent": "IfNotPresent",
+            "never": "Never",
+        }
+        v = v.lower()
+        if v not in values.keys():
+            raise ValueError("value must be always, ifnotpresent or never")
+        return values[v]
+
+
+class PrometheusCharm(CharmedOsmBase):
+
+    """Prometheus Charm."""
+
+    def __init__(self, *args) -> NoReturn:
+        """Prometheus Charm constructor."""
+        super().__init__(*args, oci_image="image")
+
+        # Registering provided relation events
+        self.prometheus = PrometheusServer(self, "prometheus")
+        self.framework.observe(
+            self.on.prometheus_relation_joined,  # pylint: disable=E1101
+            self._publish_prometheus_info,
+        )
+
+        # Registering actions
+        self.framework.observe(
+            self.on.backup_action,  # pylint: disable=E1101
+            self._on_backup_action,
+        )
+
+    def _publish_prometheus_info(self, event: EventBase) -> NoReturn:
+        config = ConfigModel(**dict(self.config))
+        self.prometheus.publish_info(
+            self.app.name,
+            PORT,
+            user=config.web_config_username,
+            password=config.web_config_password,
+        )
+
+    def _on_backup_action(self, event: EventBase) -> NoReturn:
+        url = f"http://{self.model.app.name}:{PORT}/api/v1/admin/tsdb/snapshot"
+        result = requests.post(url)
+
+        if result.status_code == 200:
+            event.set_results({"backup-name": result.json()["name"]})
+        else:
+            event.fail(f"status-code: {result.status_code}")
+
+    def _build_config_file(self, config: ConfigModel):
+        files_builder = FilesV3Builder()
+        files_builder.add_file(
+            "prometheus.yml",
+            (
+                "global:\n"
+                "  scrape_interval: 15s\n"
+                "  evaluation_interval: 15s\n"
+                "alerting:\n"
+                "  alertmanagers:\n"
+                "    - static_configs:\n"
+                "        - targets:\n"
+                "rule_files:\n"
+                "scrape_configs:\n"
+                "  - job_name: 'prometheus'\n"
+                "    static_configs:\n"
+                f"      - targets: [{config.default_target}]\n"
+            ),
+        )
+        return files_builder.build()
+
+    def _build_webconfig_file(self):
+        files_builder = FilesV3Builder()
+        files_builder.add_file("web.yml", "web-config-file", secret=True)
+        return files_builder.build()
+
+    def build_pod_spec(self, image_info):
+        # Validate config
+        config = ConfigModel(**dict(self.config))
+        # Create Builder for the PodSpec
+        pod_spec_builder = PodSpecV3Builder(
+            enable_security_context=config.security_context
+        )
+
+        # Build Backup Container
+        backup_image = OCIImageResource(self, "backup-image")
+        backup_image_info = backup_image.fetch()
+        backup_container_builder = ContainerV3Builder("prom-backup", backup_image_info)
+        backup_container = backup_container_builder.build()
+
+        # Add backup container to pod spec
+        pod_spec_builder.add_container(backup_container)
+
+        # Add pod secrets
+        prometheus_secret_name = f"{self.app.name}-secret"
+        pod_spec_builder.add_secret(
+            prometheus_secret_name,
+            {
+                "web-config-file": (
+                    "basic_auth_users:\n"
+                    f"  {config.web_config_username}: {self._hash_password(config.web_config_password)}\n"
+                )
+            },
+        )
+
+        # Build Container
+        container_builder = ContainerV3Builder(
+            self.app.name,
+            image_info,
+            config.image_pull_policy,
+            run_as_non_root=config.security_context,
+        )
+        container_builder.add_port(name=self.app.name, port=PORT)
+        token = self._base64_encode(
+            f"{config.web_config_username}:{config.web_config_password}"
+        )
+        container_builder.add_http_readiness_probe(
+            "/-/ready",
+            PORT,
+            initial_delay_seconds=10,
+            timeout_seconds=30,
+            http_headers=[("Authorization", f"Basic {token}")],
+        )
+        container_builder.add_http_liveness_probe(
+            "/-/healthy",
+            PORT,
+            initial_delay_seconds=30,
+            period_seconds=30,
+            http_headers=[("Authorization", f"Basic {token}")],
+        )
+        command = [
+            "/bin/prometheus",
+            "--config.file=/etc/prometheus/prometheus.yml",
+            "--web.config.file=/etc/prometheus/web-config/web.yml",
+            "--storage.tsdb.path=/prometheus",
+            "--web.console.libraries=/usr/share/prometheus/console_libraries",
+            "--web.console.templates=/usr/share/prometheus/consoles",
+            f"--web.route-prefix={config.web_subpath}",
+            f"--web.external-url=http://localhost:{PORT}{config.web_subpath}",
+        ]
+        if config.enable_web_admin_api:
+            command.append("--web.enable-admin-api")
+        container_builder.add_command(command)
+        container_builder.add_volume_config(
+            "config", "/etc/prometheus", self._build_config_file(config)
+        )
+        container_builder.add_volume_config(
+            "web-config",
+            "/etc/prometheus/web-config",
+            self._build_webconfig_file(),
+            secret_name=prometheus_secret_name,
+        )
+        container = container_builder.build()
+        # Add container to pod spec
+        pod_spec_builder.add_container(container)
+        # Add ingress resources to pod spec if site url exists
+        if config.site_url:
+            parsed = urlparse(config.site_url)
+            annotations = {
+                "nginx.ingress.kubernetes.io/proxy-body-size": "{}".format(
+                    str(config.max_file_size) + "m"
+                    if config.max_file_size > 0
+                    else config.max_file_size
+                )
+            }
+            if config.ingress_class:
+                annotations["kubernetes.io/ingress.class"] = config.ingress_class
+            ingress_resource_builder = IngressResourceV3Builder(
+                f"{self.app.name}-ingress", annotations
+            )
+
+            if config.ingress_whitelist_source_range:
+                annotations[
+                    "nginx.ingress.kubernetes.io/whitelist-source-range"
+                ] = config.ingress_whitelist_source_range
+
+            if config.cluster_issuer:
+                annotations["cert-manager.io/cluster-issuer"] = config.cluster_issuer
+
+            if parsed.scheme == "https":
+                ingress_resource_builder.add_tls(
+                    [parsed.hostname], config.tls_secret_name
+                )
+            else:
+                annotations["nginx.ingress.kubernetes.io/ssl-redirect"] = "false"
+
+            ingress_resource_builder.add_rule(parsed.hostname, self.app.name, PORT)
+            ingress_resource = ingress_resource_builder.build()
+            pod_spec_builder.add_ingress_resource(ingress_resource)
+        return pod_spec_builder.build()
+
+    def _hash_password(self, password):
+        hashed_password = bcrypt.hashpw(password.encode("utf-8"), bcrypt.gensalt())
+        return hashed_password.decode()
+
+    def _base64_encode(self, phrase: str) -> str:
+        return base64.b64encode(phrase.encode("utf-8")).decode("utf-8")
+
+
+if __name__ == "__main__":
+    main(PrometheusCharm)
diff --git a/installers/charm/prometheus/src/pod_spec.py b/installers/charm/prometheus/src/pod_spec.py
new file mode 100644
index 0000000..202114e
--- /dev/null
+++ b/installers/charm/prometheus/src/pod_spec.py
@@ -0,0 +1,380 @@
+#!/usr/bin/env python3
+# 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
+##
+
+from ipaddress import ip_network
+import logging
+from typing import Any, Dict, List
+from urllib.parse import urlparse
+
+logger = logging.getLogger(__name__)
+
+
+def _validate_max_file_size(max_file_size: int, site_url: str) -> bool:
+    """Validate max_file_size.
+
+    Args:
+        max_file_size (int): maximum file size allowed.
+        site_url (str): endpoint url.
+
+    Returns:
+        bool: True if valid, false otherwise.
+    """
+    if not site_url:
+        return True
+
+    parsed = urlparse(site_url)
+
+    if not parsed.scheme.startswith("http"):
+        return True
+
+    if max_file_size is None:
+        return False
+
+    return max_file_size >= 0
+
+
+def _validate_ip_network(network: str) -> bool:
+    """Validate IP network.
+
+    Args:
+        network (str): IP network range.
+
+    Returns:
+        bool: True if valid, false otherwise.
+    """
+    if not network:
+        return True
+
+    try:
+        ip_network(network)
+    except ValueError:
+        return False
+
+    return True
+
+
+def _validate_data(config_data: Dict[str, Any], relation_data: Dict[str, Any]) -> bool:
+    """Validates passed information.
+
+    Args:
+        config_data (Dict[str, Any]): configuration information.
+        relation_data (Dict[str, Any]): relation information
+
+    Raises:
+        ValueError: when config and/or relation data is not valid.
+    """
+    config_validators = {
+        "web_subpath": lambda value, _: isinstance(value, str) and len(value) > 0,
+        "default_target": lambda value, _: isinstance(value, str),
+        "site_url": lambda value, _: isinstance(value, str)
+        if value is not None
+        else True,
+        "max_file_size": lambda value, values: _validate_max_file_size(
+            value, values.get("site_url")
+        ),
+        "ingress_whitelist_source_range": lambda value, _: _validate_ip_network(value),
+        "tls_secret_name": lambda value, _: isinstance(value, str)
+        if value is not None
+        else True,
+        "enable_web_admin_api": lambda value, _: isinstance(value, bool),
+    }
+    relation_validators = {}
+    problems = []
+
+    for key, validator in config_validators.items():
+        valid = validator(config_data.get(key), config_data)
+
+        if not valid:
+            problems.append(key)
+
+    for key, validator in relation_validators.items():
+        valid = validator(relation_data.get(key), relation_data)
+
+        if not valid:
+            problems.append(key)
+
+    if len(problems) > 0:
+        raise ValueError("Errors found in: {}".format(", ".join(problems)))
+
+    return True
+
+
+def _make_pod_ports(port: int) -> List[Dict[str, Any]]:
+    """Generate pod ports details.
+
+    Args:
+        port (int): port to expose.
+
+    Returns:
+        List[Dict[str, Any]]: pod port details.
+    """
+    return [{"name": "prometheus", "containerPort": port, "protocol": "TCP"}]
+
+
+def _make_pod_envconfig(
+    config: Dict[str, Any], relation_state: Dict[str, Any]
+) -> Dict[str, Any]:
+    """Generate pod environment configuration.
+
+    Args:
+        config (Dict[str, Any]): configuration information.
+        relation_state (Dict[str, Any]): relation state information.
+
+    Returns:
+        Dict[str, Any]: pod environment configuration.
+    """
+    envconfig = {}
+
+    return envconfig
+
+
+def _make_pod_ingress_resources(
+    config: Dict[str, Any], app_name: str, port: int
+) -> List[Dict[str, Any]]:
+    """Generate pod ingress resources.
+
+    Args:
+        config (Dict[str, Any]): configuration information.
+        app_name (str): application name.
+        port (int): port to expose.
+
+    Returns:
+        List[Dict[str, Any]]: pod ingress resources.
+    """
+    site_url = config.get("site_url")
+
+    if not site_url:
+        return
+
+    parsed = urlparse(site_url)
+
+    if not parsed.scheme.startswith("http"):
+        return
+
+    max_file_size = config["max_file_size"]
+    ingress_whitelist_source_range = config["ingress_whitelist_source_range"]
+
+    annotations = {
+        "nginx.ingress.kubernetes.io/proxy-body-size": "{}".format(
+            str(max_file_size) + "m" if max_file_size > 0 else max_file_size
+        ),
+    }
+
+    if ingress_whitelist_source_range:
+        annotations[
+            "nginx.ingress.kubernetes.io/whitelist-source-range"
+        ] = ingress_whitelist_source_range
+
+    ingress_spec_tls = None
+
+    if parsed.scheme == "https":
+        ingress_spec_tls = [{"hosts": [parsed.hostname]}]
+        tls_secret_name = config["tls_secret_name"]
+        if tls_secret_name:
+            ingress_spec_tls[0]["secretName"] = tls_secret_name
+    else:
+        annotations["nginx.ingress.kubernetes.io/ssl-redirect"] = "false"
+
+    ingress = {
+        "name": "{}-ingress".format(app_name),
+        "annotations": annotations,
+        "spec": {
+            "rules": [
+                {
+                    "host": parsed.hostname,
+                    "http": {
+                        "paths": [
+                            {
+                                "path": "/",
+                                "backend": {
+                                    "serviceName": app_name,
+                                    "servicePort": port,
+                                },
+                            }
+                        ]
+                    },
+                }
+            ]
+        },
+    }
+    if ingress_spec_tls:
+        ingress["spec"]["tls"] = ingress_spec_tls
+
+    return [ingress]
+
+
+def _make_pod_files(config: Dict[str, Any]) -> List[Dict[str, Any]]:
+    """Generating ConfigMap information
+
+    Args:
+        config (Dict[str, Any]): configuration information.
+
+    Returns:
+        List[Dict[str, Any]]: ConfigMap information.
+    """
+    files = [
+        {
+            "name": "config",
+            "mountPath": "/etc/prometheus",
+            "files": [
+                {
+                    "path": "prometheus.yml",
+                    "content": (
+                        "global:\n"
+                        "  scrape_interval: 15s\n"
+                        "  evaluation_interval: 15s\n"
+                        "alerting:\n"
+                        "  alertmanagers:\n"
+                        "    - static_configs:\n"
+                        "        - targets:\n"
+                        "rule_files:\n"
+                        "scrape_configs:\n"
+                        "  - job_name: 'prometheus'\n"
+                        "    static_configs:\n"
+                        "      - targets: [{}]\n".format(config["default_target"])
+                    ),
+                }
+            ],
+        }
+    ]
+
+    return files
+
+
+def _make_readiness_probe(port: int) -> Dict[str, Any]:
+    """Generate readiness probe.
+
+    Args:
+        port (int): service port.
+
+    Returns:
+        Dict[str, Any]: readiness probe.
+    """
+    return {
+        "httpGet": {
+            "path": "/-/ready",
+            "port": port,
+        },
+        "initialDelaySeconds": 10,
+        "timeoutSeconds": 30,
+    }
+
+
+def _make_liveness_probe(port: int) -> Dict[str, Any]:
+    """Generate liveness probe.
+
+    Args:
+        port (int): service port.
+
+    Returns:
+        Dict[str, Any]: liveness probe.
+    """
+    return {
+        "httpGet": {
+            "path": "/-/healthy",
+            "port": port,
+        },
+        "initialDelaySeconds": 30,
+        "periodSeconds": 30,
+    }
+
+
+def _make_pod_command(config: Dict[str, Any], port: int) -> List[str]:
+    """Generate the startup command.
+
+    Args:
+        config (Dict[str, Any]): Configuration information.
+        port (int): port.
+
+    Returns:
+        List[str]: command to startup the process.
+    """
+    command = [
+        "/bin/prometheus",
+        "--config.file=/etc/prometheus/prometheus.yml",
+        "--storage.tsdb.path=/prometheus",
+        "--web.console.libraries=/usr/share/prometheus/console_libraries",
+        "--web.console.templates=/usr/share/prometheus/consoles",
+        "--web.route-prefix={}".format(config.get("web_subpath")),
+        "--web.external-url=http://localhost:{}{}".format(
+            port, config.get("web_subpath")
+        ),
+    ]
+    if config.get("enable_web_admin_api"):
+        command.append("--web.enable-admin-api")
+    return command
+
+
+def make_pod_spec(
+    image_info: Dict[str, str],
+    config: Dict[str, Any],
+    relation_state: Dict[str, Any],
+    app_name: str = "prometheus",
+    port: int = 9090,
+) -> Dict[str, Any]:
+    """Generate the pod spec information.
+
+    Args:
+        image_info (Dict[str, str]): Object provided by
+            OCIImageResource("image").fetch().
+        config (Dict[str, Any]): Configuration information.
+        relation_state (Dict[str, Any]): Relation state information.
+        app_name (str, optional): Application name. Defaults to "ro".
+        port (int, optional): Port for the container. Defaults to 9090.
+
+    Returns:
+        Dict[str, Any]: Pod spec dictionary for the charm.
+    """
+    if not image_info:
+        return None
+
+    _validate_data(config, relation_state)
+
+    ports = _make_pod_ports(port)
+    env_config = _make_pod_envconfig(config, relation_state)
+    files = _make_pod_files(config)
+    readiness_probe = _make_readiness_probe(port)
+    liveness_probe = _make_liveness_probe(port)
+    ingress_resources = _make_pod_ingress_resources(config, app_name, port)
+    command = _make_pod_command(config, port)
+
+    return {
+        "version": 3,
+        "containers": [
+            {
+                "name": app_name,
+                "imageDetails": image_info,
+                "imagePullPolicy": "Always",
+                "ports": ports,
+                "envConfig": env_config,
+                "volumeConfig": files,
+                "command": command,
+                "kubernetes": {
+                    "readinessProbe": readiness_probe,
+                    "livenessProbe": liveness_probe,
+                },
+            }
+        ],
+        "kubernetesResources": {
+            "ingressResources": ingress_resources or [],
+        },
+    }