Add workload version to juju status

src/synapse/api.py

@@ -25,6 +25,7 @@
 SYNAPSE_URL = "http://localhost:8008"
 REGISTER_URL = f"{SYNAPSE_URL}/_synapse/admin/v1/register"
 VERSION_URL = f"{SYNAPSE_URL}/_synapse/admin/v1/server_version"
+SYNAPSE_VERSION_REGEX = r"(\d+\.\d+\.\d+(?:\w+)?)\s?"
 
 
 class APIError(Exception):
@@ -35,22 +36,30 @@ class APIError(Exception):
     """
 
     def __init__(self, msg: str):
-        """Initialize a new instance of the RegisterUserError exception.
+        """Initialize a new instance of the APIError exception.
 
         Args:
             msg (str): Explanation of the error.
         """
         self.msg = msg
 
 
-class RegisterUserError(APIError):
-    """Exception raised when registering user via API fails."""
-
-
 class NetworkError(APIError):
     """Exception raised when requesting API fails due network issues."""
 
 
+class GetVersionError(APIError):
+    """Exception raised when getting version via API fails."""
+
+
+class VersionNotFoundError(GetVersionError):
+    """Exception raised when version is not found."""
+
+
+class VersionUnexpectedContentError(GetVersionError):
+    """Exception raised when output of getting version is unexpected."""
+
+
 def register_user(registration_shared_secret: str, user: User) -> None:
     """Register user.
 
@@ -172,6 +181,7 @@ def get_version() -> str:
 
     Raises:
         NetworkError: if there was an error fetching the version.
+        GetVersionError: if there was an error while reading version.
     """
     try:
         session = Session()
@@ -182,15 +192,26 @@ def get_version() -> str:
         session.mount("http://", HTTPAdapter(max_retries=retries))
         res = session.get(VERSION_URL, timeout=10)
         res.raise_for_status()
-        server_version = res.json()["server_version"]
-        version_match = re.search(r"^([^\s(]+)", server_version)
-        if version_match:
-            return version_match.group(1)
-        return server_version
-    except (
-        requests.exceptions.ConnectionError,
-        requests.exceptions.Timeout,
-        requests.exceptions.HTTPError,
-    ) as exc:
-        logger.exception("Failed to request %s : %r", VERSION_URL, exc)
-        raise NetworkError(f"Failed to request {VERSION_URL}.") from exc
+        res_json = res.json()
+        server_version = res_json.get("server_version", None)
+        if server_version is None:
+            # Exception not in docstring because is captured.
+            raise VersionNotFoundError(  # noqa: DCO053
+                f"There is no server_version in JSON output: {res_json}"
+            )
+        version_match = re.search(SYNAPSE_VERSION_REGEX, server_version)
+        if not version_match:
+            # Exception not in docstring because is captured.
+            raise VersionUnexpectedContentError(  # noqa: DCO053
+                f"server_version has unexpected content: {server_version}"
+            )
+        return version_match.group(1)
+    except (requests.exceptions.ConnectionError, requests.exceptions.Timeout) as exc:
+        logger.exception("Failed to connect to %s: %r", VERSION_URL, exc)
+        raise NetworkError(f"Failed to connect to {VERSION_URL}.") from exc
+    except requests.exceptions.HTTPError as exc:
+        logger.exception("HTTP error from %s: %r", VERSION_URL, exc)
+        raise NetworkError(f"HTTP error from {VERSION_URL}.") from exc
+    except GetVersionError as exc:
+        logger.exception("Failed to get version: %r", exc)
+        raise GetVersionError(str(exc)) from exc

src/synapse/workload.py

@@ -23,6 +23,8 @@
     SYNAPSE_PORT,
 )
 
+from .api import VERSION_URL
+
 logger = logging.getLogger(__name__)
 
 
@@ -77,7 +79,7 @@ def check_ready() -> typing.Dict:
     check = Check(CHECK_READY_NAME)
     check.override = "replace"
     check.level = "ready"
-    check.http = {"url": f"http://localhost:{SYNAPSE_PORT}/_synapse/admin/v1/server_version"}
+    check.http = {"url": VERSION_URL}
     # _CheckDict cannot be imported
     return check.to_dict()  # type: ignore
 

tests/integration/test_charm.py

@@ -17,6 +17,7 @@
 from pytest_operator.plugin import OpsTest
 
 from constants import SYNAPSE_PORT
+from synapse.api import SYNAPSE_VERSION_REGEX
 
 # caused by pytest fixtures
 # pylint: disable=too-many-arguments
@@ -253,6 +254,6 @@ async def test_workload_version(
             f"http://{unit_ip}:{SYNAPSE_PORT}/_synapse/admin/v1/server_version", timeout=5
         )
         server_version = res.json()["server_version"]
-        version_match = re.search(r"^([^\s(]+)", server_version)
+        version_match = re.search(SYNAPSE_VERSION_REGEX, server_version)
         assert version_match
         assert version_match.group(1) == juju_workload_version

tests/unit/test_charm.py

@@ -22,7 +22,7 @@
 
 def test_synapse_pebble_layer(harness_server_name_configured: Harness) -> None:
     """
-    arrange: none
+    arrange: charm deployed.
     act: start the Synapse charm, set Synapse container to be ready and set server_name.
     assert: Synapse charm should submit the correct Synapse pebble layer to pebble.
     """
@@ -53,7 +53,7 @@ def test_synapse_pebble_layer(harness_server_name_configured: Harness) -> None:
 )
 def test_synapse_migrate_config_error(harness_server_name_configured: Harness) -> None:
     """
-    arrange: none
+    arrange: charm deployed.
     act: start the Synapse charm, set Synapse container to be ready and set server_name.
     assert: Synapse charm should be blocked by error on migrate_config command.
     """
@@ -64,7 +64,7 @@ def test_synapse_migrate_config_error(harness_server_name_configured: Harness) -
 
 def test_container_down(harness_server_name_configured: Harness) -> None:
     """
-    arrange: none
+    arrange: charm deployed.
     act: start the Synapse charm, set server_name, set Synapse container to be down
         and then try to change report_stats.
     assert: Synapse charm should submit the correct status.
@@ -78,7 +78,7 @@ def test_container_down(harness_server_name_configured: Harness) -> None:
 
 def test_server_name_empty(harness: Harness) -> None:
     """
-    arrange: none
+    arrange: charm deployed.
     act: start the Synapse charm and set Synapse container to be ready.
     assert: Synapse charm waits for server_name to be set.
     """

tests/unit/test_synapse_api.py

@@ -87,7 +87,7 @@ def test_generate_mac():
 @mock.patch("synapse.api.requests")
 def test_get_nonce_success(mock_requests):
     """
-    arrange: none.
+    arrange: mock request to get nonce returning value.
     act: get nonce.
     assert: _get_nonce return the correct value.
     """
@@ -102,7 +102,7 @@ def test_get_nonce_success(mock_requests):
 
 def test_get_nonce_error(monkeypatch: pytest.MonkeyPatch):
     """
-    arrange: none.
+    arrange: mock request to get nonce returning error.
     act: get nonce.
     assert: NetworkError is raised.
     """
@@ -116,7 +116,7 @@ def test_get_nonce_error(monkeypatch: pytest.MonkeyPatch):
 @mock.patch("synapse.api.Session")
 def test_get_version_success(mock_session):
     """
-    arrange: none.
+    arrange: mock request to get version returning value.
     act: get version.
     assert: get_version return the correct value.
     """
@@ -131,9 +131,9 @@ def test_get_version_success(mock_session):
 
 
 @mock.patch("synapse.api.Session")
-def test_get_version_error(mock_session):
+def test_get_version_connection_error(mock_session):
     """
-    arrange: none.
+    arrange: mock request to get version returning error.
     act: get version.
     assert: NetworkError is raised.
     """
@@ -142,5 +142,20 @@ def test_get_version_error(mock_session):
     mock_response_error = requests.exceptions.ConnectionError("Connection error")
     mock_response.json.side_effect = mock_response_error
     mock_session_instance.get.return_value = mock_response
-    with pytest.raises(synapse.APIError, match="Failed to request"):
+    with pytest.raises(synapse.APIError, match="Failed to connect to"):
+        synapse.api.get_version()
+
+
+@mock.patch("synapse.api.Session")
+def test_get_version_regex_error(mock_session):
+    """
+    arrange: mock request to get version returning invalid content.
+    act: get version.
+    assert: get_version return the correct value.
+    """
+    mock_session_instance = mock_session.return_value
+    mock_response = mock.Mock()
+    mock_response.json.return_value = {"server_version": "foo"}
+    mock_session_instance.get.return_value = mock_response
+    with pytest.raises(synapse.APIError, match="server_version has unexpected content"):
         synapse.api.get_version()