Add revision to the dashboard title of the Grafana

With this change, two different OpenSearch applications, in
different revisions, will have separate dashboards when related
to COS.

- data-platform-helpers was added to use the get_charm_revision
- titles of dashboards are changed during the charm upgrade hook
- config_changed was added on refresh_events of COSAgentProvider
  to re-render the dashboards after a charm upgrade

lib/charms/opensearch/v0/helper_charm.py

@@ -2,10 +2,12 @@
 # See LICENSE file for licensing details.
 
 """Utility functions for charms related operations."""
+import json
 import logging
 import os
 import re
 import subprocess
+from pathlib import Path
 from time import time_ns
 from types import SimpleNamespace
 from typing import TYPE_CHECKING, List, Union
@@ -15,6 +17,7 @@
 from charms.opensearch.v0.models import App, PeerClusterApp
 from charms.opensearch.v0.opensearch_exceptions import OpenSearchCmdError
 from charms.opensearch.v0.opensearch_internal_data import Scope
+from data_platform_helpers.version_check import get_charm_revision
 from ops import CharmBase
 from ops.model import ActiveStatus, StatusBase, Unit
 
@@ -228,3 +231,44 @@ def mask_sensitive_information(cmd: str) -> str:
     pattern = re.compile(r"(-tspass\s+|-kspass\s+|-storepass\s+|-new\s+|pass:)(\S+)")
 
     return re.sub(pattern, r"\1" + "xxx", cmd)
+
+
+def update_grafana_dashboards_titles(charm: "OpenSearchBaseCharm") -> None:
+    """Update the titles in the specified directory to include the charm revision."""
+    revision = get_charm_revision(charm.model.unit)
+    path = charm.charm_dir / "src/grafana_dashboards"
+
+    for dashboard_path in path.iterdir():
+        if dashboard_path.is_file() and dashboard_path.suffix == ".json":
+            try:
+                _update_dashboard_title(revision, dashboard_path)
+            except (json.JSONDecodeError, IOError) as e:
+                logger.error("Failed to process %s: %s", dashboard_path.name, str(e))
+        else:
+            logger.warning("%s is not a valid JSON file", dashboard_path.name)
+
+
+def _update_dashboard_title(revision: str, dashboard_path: Path) -> None:
+    """Update the title of a Grafana dashboard file to include the charm revision."""
+    with open(dashboard_path, "r") as file:
+        dashboard = json.load(file)
+
+    old_title = dashboard.get("title")
+    if old_title:
+        title_prefix = old_title.split(" - Rev")[0]
+        new_title = f"{old_title} - Rev {revision}"
+        dashboard["title"] = f"{title_prefix} - Rev {revision}"
+
+        logger.info(
+            "Changing the title of dashboard %s from %s to %s",
+            dashboard_path.name,
+            old_title,
+            new_title,
+        )
+
+        with open(dashboard_path, "w") as file:
+            json.dump(dashboard, file, indent=4)
+    else:
+        logger.warning(
+            "Dashboard %s does not have title and cannot be updated", dashboard_path.name
+        )

lib/charms/opensearch/v0/opensearch_base_charm.py

@@ -244,6 +244,7 @@ def __init__(self, *args, distro: Type[OpenSearchDistribution] = None):
             metrics_endpoints=[],
             scrape_configs=self._scrape_config,
             refresh_events=[
+                self.on.config_changed,
                 self.on.set_password_action,
                 self.on.secret_changed,
                 self.on[PeerRelationName].relation_changed,

pyproject.toml

@@ -23,6 +23,7 @@ pydantic = "^1.10.17, <2"
 cryptography = "^43.0.0"
 jsonschema = "^4.23.0"
 poetry-core = "^1.9.0"
+data-platform-helpers = "^0.1.4"
 
 
 [tool.poetry.group.charm-libs.dependencies]

src/charm.py

@@ -9,6 +9,7 @@
 
 import ops
 from charms.opensearch.v0.constants_charm import InstallError, InstallProgress
+from charms.opensearch.v0.helper_charm import update_grafana_dashboards_titles
 from charms.opensearch.v0.models import PerformanceType
 from charms.opensearch.v0.opensearch_base_charm import OpenSearchBaseCharm
 from charms.opensearch.v0.opensearch_exceptions import OpenSearchInstallError
@@ -137,6 +138,7 @@ def _set_upgrade_status(self):
                 logger.debug(f"Set app status to {self.app.status}")
 
     def _on_upgrade_charm(self, _):
+        update_grafana_dashboards_titles(self)
         if not self.performance_profile.current:
             # We are running (1) install or (2) an upgrade on instance that pre-dates profile
             # First, we set this unit's effective profile -> 1G heap and no index templates.

tests/unit/lib/test_helper_charm.py

@@ -3,10 +3,18 @@
 
 """Unit test for the helper_cluster library."""
 
+import json
 import unittest
+from pathlib import Path
+from unittest.mock import MagicMock, PropertyMock, call, mock_open, patch
 
 from charms.opensearch.v0.constants_charm import PeerRelationName
-from charms.opensearch.v0.helper_charm import Status, mask_sensitive_information
+from charms.opensearch.v0.helper_charm import (
+    Status,
+    _update_dashboard_title,
+    mask_sensitive_information,
+    update_grafana_dashboards_titles,
+)
 from ops.model import BlockedStatus, MaintenanceStatus, WaitingStatus
 from ops.testing import Harness
 
@@ -64,3 +72,120 @@ def test_mask_sensitive_information(self):
 
         actual_result = mask_sensitive_information(command_to_test)
         assert actual_result == expected_result
+
+
+class TestCOSGrafanaDashboard(unittest.TestCase):
+
+    @patch("charms.opensearch.v0.helper_charm.get_charm_revision", return_value=167)
+    @patch("charms.opensearch.v0.helper_charm.Path.iterdir")
+    @patch("charms.opensearch.v0.helper_charm._update_dashboard_title")
+    def test_update_grafana_dashboards_titles(self, mock_update_dashboard, mock_iterdir, _):
+        mock_charm = MagicMock()
+        mock_charm.model.unit = MagicMock()
+        type(mock_charm).charm_dir = PropertyMock(return_value=Path("/fake/charm/dir"))
+
+        mock_json_file_1 = MagicMock(spec=Path)
+        mock_json_file_1.is_file.return_value = True
+        mock_json_file_1.suffix = ".json"
+        mock_json_file_1.name = "dashboard1.json"
+
+        mock_non_json_file = MagicMock(spec=Path)
+        mock_non_json_file.is_file.return_value = True
+        mock_non_json_file.suffix = ".txt"
+        mock_non_json_file.name = "not_a_dashboard.txt"
+
+        mock_json_file_2 = MagicMock(spec=Path)
+        mock_json_file_2.is_file.return_value = True
+        mock_json_file_2.suffix = ".json"
+        mock_json_file_2.name = "dashboard2.json"
+
+        mock_iterdir.return_value = [mock_json_file_1, mock_non_json_file, mock_json_file_2]
+
+        update_grafana_dashboards_titles(mock_charm)
+
+        # non-json files are not called
+        mock_update_dashboard.assert_has_calls(
+            [
+                call(167, mock_json_file_1),
+                call(167, mock_json_file_2),
+            ],
+            any_order=True,
+        )
+
+        self.assertEqual(mock_update_dashboard.call_count, 2)
+
+    @patch("charms.opensearch.v0.helper_charm.get_charm_revision", return_value=167)
+    @patch("charms.opensearch.v0.helper_charm.logger")
+    @patch("charms.opensearch.v0.helper_charm.Path.iterdir")
+    @patch("charms.opensearch.v0.helper_charm._update_dashboard_title")
+    def test_update_grafana_dashboards_titles_json_exception(
+        self, mock_update_dashboard, mock_iterdir, mock_logger, _
+    ):
+        mock_charm = MagicMock()
+        mock_charm.model.unit = MagicMock()
+        type(mock_charm).charm_dir = PropertyMock(return_value=Path("/fake/charm/dir"))
+
+        mock_json_file_1 = MagicMock(spec=Path)
+        mock_json_file_1.is_file.return_value = True
+        mock_json_file_1.suffix = ".json"
+        mock_json_file_1.name = "dashboard1.json"
+
+        mock_iterdir.return_value = [mock_json_file_1]
+
+        mock_update_dashboard.side_effect = json.JSONDecodeError("Error", "Error", 0)
+
+        update_grafana_dashboards_titles(mock_charm)
+
+        mock_logger.error.assert_called_once()
+
+    @patch(
+        "builtins.open",
+        new_callable=mock_open,
+        read_data=json.dumps({"title": "Charmed OpenSearch"}),
+    )
+    @patch("json.dump")
+    def test_update_dashboard_title_no_prior_revision(self, mock_json_dump, mock_open_func):
+
+        _update_dashboard_title(167, MagicMock())
+
+        expected_updated_dashboard = {"title": "Charmed OpenSearch - Rev 167"}
+        mock_json_dump.assert_called_once_with(
+            expected_updated_dashboard, mock_open_func(), indent=4
+        )
+
+    @patch(
+        "builtins.open",
+        new_callable=mock_open,
+        read_data=json.dumps({"title": "Charmed OpenSearch - Rev 166"}),
+    )
+    @patch("json.dump")
+    def test_update_dashboard_title_prior_revision(
+        self,
+        mock_json_dump,
+        mock_open_func,
+    ):
+
+        _update_dashboard_title("167", MagicMock())
+
+        expected_updated_dashboard = {"title": "Charmed OpenSearch - Rev 167"}
+        mock_json_dump.assert_called_once_with(
+            expected_updated_dashboard, mock_open_func(), indent=4
+        )
+
+    @patch("charms.opensearch.v0.helper_charm.logger")
+    @patch(
+        "builtins.open",
+        new_callable=mock_open,
+        read_data=json.dumps({"my-content": "content"}),
+    )
+    @patch("json.dump")
+    def test_update_dashboard_title_json_no_title(
+        self,
+        _,
+        __,
+        mock_logger,
+    ):
+
+        _update_dashboard_title("167", MagicMock())
+
+        mock_logger.warning.assert_called_once()