fix: prevent hooks before preconditions ready (#75)

* fix: prevent hooks before preconditions ready

* fix: check /proc/mounts for storage mount validation

* chore: refactor storage check to state

* fix: circular imports

src-docs/actions.py.md

@@ -5,6 +5,9 @@
 # <kbd>module</kbd> `actions.py`
 Jenkins charm actions. 
 
+**Global Variables**
+---------------
+- **JENKINS_SERVICE_NAME**
 
 
 ---

src-docs/agent.py.md

@@ -9,6 +9,7 @@ The Jenkins agent relation observer.
 ---------------
 - **AGENT_RELATION**
 - **DEPRECATED_AGENT_RELATION**
+- **JENKINS_SERVICE_NAME**
 
 
 ---

src-docs/charm.py.md

@@ -5,14 +5,17 @@
 # <kbd>module</kbd> `charm.py`
 Charm Jenkins. 
 
+**Global Variables**
+---------------
+- **JENKINS_SERVICE_NAME**
 
 
 ---
 
 ## <kbd>class</kbd> `JenkinsK8sOperatorCharm`
 Charm Jenkins. 
 
-<a href="../src/charm.py#L36"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/charm.py#L37"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>function</kbd> `__init__`
 

src-docs/state.py.md

@@ -9,6 +9,8 @@ Jenkins States.
 ---------------
 - **AGENT_RELATION**
 - **DEPRECATED_AGENT_RELATION**
+- **JENKINS_SERVICE_NAME**
+- **JENKINS_HOME_STORAGE_NAME**
 
 
 ---
@@ -29,7 +31,7 @@ Metadata for registering Jenkins Agent.
 
 ---
 
-<a href="../src/state.py#L119"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/state.py#L123"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>classmethod</kbd> `from_agent_relation`
 
@@ -54,7 +56,7 @@ Instantiate AgentMeta from charm relation databag.
 
 ---
 
-<a href="../src/state.py#L100"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/state.py#L104"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>classmethod</kbd> `from_deprecated_agent_relation`
 
@@ -79,7 +81,7 @@ Instantiate AgentMeta from charm relation databag.
 
 ---
 
-<a href="../src/state.py#L87"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/state.py#L91"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>classmethod</kbd> `numeric_executors`
 
@@ -112,7 +114,7 @@ Exception raised when a charm configuration is found to be invalid.
 
  - <b>`msg`</b>:  Explanation of the error. 
 
-<a href="../src/state.py#L33"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/state.py#L37"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>function</kbd> `__init__`
 
@@ -143,7 +145,7 @@ Represents an error with invalid number of units deployed.
 
  - <b>`msg`</b>:  Explanation of the error. 
 
-<a href="../src/state.py#L65"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/state.py#L69"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>function</kbd> `__init__`
 
@@ -174,7 +176,7 @@ Represents an error with invalid data in relation data.
 
  - <b>`msg`</b>:  Explanation of the error. 
 
-<a href="../src/state.py#L49"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/state.py#L53"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>function</kbd> `__init__`
 
@@ -221,7 +223,7 @@ Configuration for accessing Jenkins through proxy.
 
 ---
 
-<a href="../src/state.py#L199"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/state.py#L203"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>classmethod</kbd> `from_env`
 
@@ -249,16 +251,16 @@ The Jenkins k8s operator charm state.
  - <b>`restart_time_range`</b>:  Time range to allow Jenkins to update version. 
  - <b>`agent_relation_meta`</b>:  Metadata of all agents from units related through agent relation. 
  - <b>`deprecated_agent_relation_meta`</b>:  Metadata of all agents from units related through  deprecated agent relation. 
+ - <b>`is_storage_ready`</b>:  Whether the Jenkins home storage is mounted. 
  - <b>`proxy_config`</b>:  Proxy configuration to access Jenkins upstream through. 
  - <b>`plugins`</b>:  The list of allowed plugins to install. 
- - <b>`jenkins_service_name`</b>:  The Jenkins service name. Note that the container name is the same. 
 
 
 
 
 ---
 
-<a href="../src/state.py#L240"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/state.py#L260"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>classmethod</kbd> `from_charm`
 

src/actions.py

@@ -6,7 +6,7 @@
 import ops
 
 import jenkins
-from state import State
+from state import JENKINS_SERVICE_NAME, State
 
 
 class Observer(ops.Object):
@@ -35,9 +35,9 @@ def on_get_admin_password(self, event: ops.ActionEvent) -> None:
         Args:
             event: The event fired from get-admin-password action.
         """
-        container = self.charm.unit.get_container(self.state.jenkins_service_name)
-        if not container.can_connect():
-            event.fail("Container not yet ready.")
+        container = self.charm.unit.get_container(JENKINS_SERVICE_NAME)
+        if not container.can_connect() or not self.state.is_storage_ready:
+            event.fail("Service not yet ready.")
             return
         credentials = jenkins.get_admin_credentials(container)
         event.set_results({"password": credentials.password_or_token})
@@ -48,9 +48,9 @@ def on_rotate_credentials(self, event: ops.ActionEvent) -> None:
         Args:
             event: The rotate credentials event.
         """
-        container = self.charm.unit.get_container(self.state.jenkins_service_name)
-        if not container.can_connect():
-            event.fail("Container not yet ready.")
+        container = self.charm.unit.get_container(JENKINS_SERVICE_NAME)
+        if not container.can_connect() or not self.state.is_storage_ready:
+            event.fail("Service not yet ready.")
             return
         try:
             password = jenkins.rotate_credentials(container)

src/agent.py

@@ -8,7 +8,7 @@
 import ops
 
 import jenkins
-from state import AGENT_RELATION, DEPRECATED_AGENT_RELATION, AgentMeta, State
+from state import AGENT_RELATION, DEPRECATED_AGENT_RELATION, JENKINS_SERVICE_NAME, AgentMeta, State
 
 logger = logging.getLogger(__name__)
 
@@ -60,9 +60,8 @@ def _on_deprecated_agent_relation_joined(self, event: ops.RelationJoinedEvent) -
         Args:
             event: The event fired from an agent joining the relationship.
         """
-        container = self.charm.unit.get_container(self.state.jenkins_service_name)
-        if not container.can_connect():
-            event.defer()
+        container = self.charm.unit.get_container(JENKINS_SERVICE_NAME)
+        if not container.can_connect() or not self.state.is_storage_ready:
             return
         # The relation is joined, it cannot be None, hence the type casting.
         deprecated_agent_relation_meta = typing.cast(
@@ -100,9 +99,8 @@ def _on_agent_relation_joined(self, event: ops.RelationJoinedEvent) -> None:
         Args:
             event: The event fired from an agent joining the relationship.
         """
-        container = self.charm.unit.get_container(self.state.jenkins_service_name)
-        if not container.can_connect():
-            event.defer()
+        container = self.charm.unit.get_container(JENKINS_SERVICE_NAME)
+        if not container.can_connect() or not self.state.is_storage_ready:
             return
         # The relation is joined, it cannot be None, hence the type casting.
         agent_relation_meta = typing.cast(
@@ -144,9 +142,8 @@ def _on_deprecated_agent_relation_departed(self, event: ops.RelationDepartedEven
             event: The event fired when a unit in deprecated agent relation is departed.
         """
         # the event unit cannot be None.
-        container = self.charm.unit.get_container(self.state.jenkins_service_name)
-        if not container.can_connect():
-            event.defer()
+        container = self.charm.unit.get_container(JENKINS_SERVICE_NAME)
+        if not container.can_connect() or not self.state.is_storage_ready:
             return
 
         # The relation data is removed before this particular hook runs, making the name set by the
@@ -172,9 +169,8 @@ def _on_agent_relation_departed(self, event: ops.RelationDepartedEvent) -> None:
             event: The event fired when a unit in agent relation is departed.
         """
         # the event unit cannot be None.
-        container = self.charm.unit.get_container(self.state.jenkins_service_name)
-        if not container.can_connect():
-            event.defer()
+        container = self.charm.unit.get_container(JENKINS_SERVICE_NAME)
+        if not container.can_connect() or not self.state.is_storage_ready:
             return
 
         # The relation data is removed before this particular hook runs, making the name set by the

src/charm.py

@@ -17,6 +17,7 @@
 import jenkins
 import timerange
 from state import (
+    JENKINS_SERVICE_NAME,
     CharmConfigInvalidError,
     CharmIllegalNumUnitsError,
     CharmRelationDataInvalidError,
@@ -74,7 +75,7 @@ def _get_pebble_layer(self, jenkins_env: jenkins.Environment) -> ops.pebble.Laye
             "summary": "jenkins layer",
             "description": "pebble config layer for jenkins",
             "services": {
-                self.state.jenkins_service_name: {
+                JENKINS_SERVICE_NAME: {
                     "override": "replace",
                     "summary": "jenkins",
                     "command": f"java -D{jenkins.SYSTEM_PROPERTY_HEADLESS} "
@@ -105,8 +106,9 @@ def _on_jenkins_pebble_ready(self, event: ops.PebbleReadyEvent) -> None:
         Args:
             event: The event fired when pebble is ready.
         """
-        container = event.workload
-        if not container or not container.can_connect():
+        container = self.unit.get_container(JENKINS_SERVICE_NAME)
+        if not container or not container.can_connect() or not self.state.is_storage_ready:
+            self.unit.status = ops.WaitingStatus("Waiting for container/storage.")
             event.defer()
             return
 
@@ -123,7 +125,7 @@ def _on_jenkins_pebble_ready(self, event: ops.PebbleReadyEvent) -> None:
             self.unit.status = ops.MaintenanceStatus("Configuring Jenkins.")
             jenkins.bootstrap(container, self.state.proxy_config)
             # Second Jenkins server start restarts Jenkins to bypass Wizard setup.
-            container.restart(self.state.jenkins_service_name)
+            container.restart(JENKINS_SERVICE_NAME)
             jenkins.wait_ready()
         except TimeoutError as exc:
             logger.error("Timed out waiting for Jenkins, %s", exc)
@@ -171,8 +173,9 @@ def _on_update_status(self, _: ops.UpdateStatusEvent) -> None:
         1. Remove plugins that are installed but are not allowed by plugins config value.
         2. Update Jenkins patch version if available and is within restart-time-range config value.
         """
-        container = self.unit.get_container(self.state.jenkins_service_name)
-        if not container.can_connect():
+        container = self.unit.get_container(JENKINS_SERVICE_NAME)
+        if not container.can_connect() or not self.state.is_storage_ready:
+            self.unit.status = ops.WaitingStatus("Waiting for container/storage.")
             return
 
         if self.state.restart_time_range and not timerange.check_now_within_bound_hours(
@@ -188,9 +191,9 @@ def _on_jenkins_home_storage_attached(self, event: ops.StorageAttachedEvent) ->
         Args:
             event: The event fired when the storage is attached.
         """
-        container = self.unit.get_container(self.state.jenkins_service_name)
+        container = self.unit.get_container(JENKINS_SERVICE_NAME)
         if not container.can_connect():
-            event.defer()
+            self.unit.status = ops.WaitingStatus("Waiting for pebble.")
             return
 
         command = [

src/jenkins.py

@@ -22,30 +22,30 @@
 from pydantic import HttpUrl
 
 import state
+from state import JENKINS_HOME_PATH
 
 logger = logging.getLogger(__name__)
 
 WEB_PORT = 8080
 WEB_URL = f"http://localhost:{WEB_PORT}"
 LOGIN_URL = f"{WEB_URL}/login?from=%2F"
-HOME_PATH = Path("/var/lib/jenkins")
 EXECUTABLES_PATH = Path("/srv/jenkins/")
 # Path to initial Jenkins password file
-PASSWORD_FILE_PATH = HOME_PATH / "secrets/initialAdminPassword"
+PASSWORD_FILE_PATH = JENKINS_HOME_PATH / "secrets/initialAdminPassword"
 # Path to Jenkins admin API token
-API_TOKEN_PATH = HOME_PATH / "secrets/apiToken"
+API_TOKEN_PATH = JENKINS_HOME_PATH / "secrets/apiToken"
 # Path to last executed Jenkins version file, required to override wizard installation
-LAST_EXEC_VERSION_PATH = HOME_PATH / Path("jenkins.install.InstallUtil.lastExecVersion")
+LAST_EXEC_VERSION_PATH = JENKINS_HOME_PATH / Path("jenkins.install.InstallUtil.lastExecVersion")
 # Path to Jenkins version file, required to override wizard installation
-WIZARD_VERSION_PATH = HOME_PATH / Path("jenkins.install.UpgradeWizard.state")
+WIZARD_VERSION_PATH = JENKINS_HOME_PATH / Path("jenkins.install.UpgradeWizard.state")
 # The Jenkins bootstrapping config path
-CONFIG_FILE_PATH = HOME_PATH / "config.xml"
+CONFIG_FILE_PATH = JENKINS_HOME_PATH / "config.xml"
 # The Jenkins plugins installation directory
-PLUGINS_PATH = HOME_PATH / "plugins"
+PLUGINS_PATH = JENKINS_HOME_PATH / "plugins"
 # The Jenkins logging configuration path
-LOGGING_CONFIG_PATH = HOME_PATH / "logging.properties"
+LOGGING_CONFIG_PATH = JENKINS_HOME_PATH / "logging.properties"
 # The Jenkins logging path as defined in templates/logging.properties file
-LOGGING_PATH = HOME_PATH / "jenkins.log"
+LOGGING_PATH = JENKINS_HOME_PATH / "jenkins.log"
 
 # The plugins that are required for Jenkins to work
 REQUIRED_PLUGINS = [
@@ -218,7 +218,7 @@ def calculate_env() -> Environment:
     Returns:
         The dictionary mapping of environment variables for the Jenkins service.
     """
-    return Environment(JENKINS_HOME=str(HOME_PATH))
+    return Environment(JENKINS_HOME=str(JENKINS_HOME_PATH))
 
 
 def get_version() -> str:

src/state.py

@@ -7,6 +7,7 @@
 import logging
 import os
 import typing
+from pathlib import Path
 
 import ops
 from pydantic import BaseModel, Field, HttpUrl, ValidationError, validator
@@ -17,6 +18,9 @@
 
 AGENT_RELATION = "agent"
 DEPRECATED_AGENT_RELATION = "agent-deprecated"
+JENKINS_SERVICE_NAME = "jenkins"
+JENKINS_HOME_STORAGE_NAME = "jenkins-home"
+JENKINS_HOME_PATH = Path("/var/lib/jenkins")
 
 
 class CharmStateBaseError(Exception):
@@ -214,6 +218,22 @@ def from_env(cls) -> typing.Optional["ProxyConfig"]:
         )
 
 
+def _is_storage_ready(charm: ops.CharmBase) -> bool:
+    """Return whether the Jenkins home storage is mounted.
+
+    Args:
+        charm: The Jenkins k8s charm.
+
+    Returns:
+        True if storage is mounted, False otherwise.
+    """
+    container = charm.unit.get_container(JENKINS_SERVICE_NAME)
+    if not container.can_connect():
+        return False
+    mount_info: str = container.pull("/proc/mounts").read()
+    return str(JENKINS_HOME_PATH) in mount_info
+
+
 @dataclasses.dataclass(frozen=True)
 class State:
     """The Jenkins k8s operator charm state.
@@ -223,9 +243,9 @@ class State:
         agent_relation_meta: Metadata of all agents from units related through agent relation.
         deprecated_agent_relation_meta: Metadata of all agents from units related through
             deprecated agent relation.
+        is_storage_ready: Whether the Jenkins home storage is mounted.
         proxy_config: Proxy configuration to access Jenkins upstream through.
         plugins: The list of allowed plugins to install.
-        jenkins_service_name: The Jenkins service name. Note that the container name is the same.
     """
 
     restart_time_range: typing.Optional[Range]
@@ -235,7 +255,7 @@ class State:
     ]
     proxy_config: typing.Optional[ProxyConfig]
     plugins: typing.Optional[typing.Iterable[str]]
-    jenkins_service_name: str = "jenkins"
+    is_storage_ready: bool
 
     @classmethod
     def from_charm(cls, charm: ops.CharmBase) -> "State":
@@ -295,6 +315,7 @@ def from_charm(cls, charm: ops.CharmBase) -> "State":
             restart_time_range=restart_time_range,
             agent_relation_meta=agent_relation_meta_map,
             deprecated_agent_relation_meta=deprecated_agent_meta_map,
+            is_storage_ready=_is_storage_ready(charm=charm),
             plugins=plugins,
             proxy_config=proxy_config,
         )