cc_modules: set default meta frequency value when no config available

[blackboxsw]

Proposed Commit Message

Each cloud-config module defines meta["frequency"] module attribute.
This frequency will be preferred unless overrides are given in
/etc/cloud/cloud.cfg module definitions.

Additional Context

Test Steps

Checklist:

• My code follows the process laid out in the documentation
• I have updated or added any unit tests accordingly
• I have updated or added any documentation accordingly

[TheRealFalcon]

Additional test if you want it. It's only checking logs, but hopefully our logs aren't lying to us.

diff --git a/tests/integration_tests/modules/test_combined.py b/tests/integration_tests/modules/test_combined.py
index eb45062e..58262ce1 100644
--- a/tests/integration_tests/modules/test_combined.py
+++ b/tests/integration_tests/modules/test_combined.py
@@ -5,12 +5,16 @@ of the test would be unlikely to affect the running of another test using
 the same instance launch. Most independent module coherence tests can go
 here.
 """
+import glob
+import importlib
 import json
 import re
 import uuid
+from pathlib import Path
 
 import pytest
 
+import cloudinit.config
 from tests.integration_tests.clouds import ImageSpecification
 from tests.integration_tests.decorators import retry
 from tests.integration_tests.instances import IntegrationInstance
@@ -223,6 +227,25 @@ class TestCombined:
             class_client.execute("stat -c %N /run/cloud-init/cloud-id")
         )
 
+    def test_run_frequency(self, class_client: IntegrationInstance):
+        log = class_client.read_from_file("/var/log/cloud-init.log")
+        config_dir = Path(cloudinit.config.__file__).parent
+        module_paths = glob.glob(str(config_dir / "cc*.py"))
+        module_names = [Path(x).stem for x in module_paths]
+        found_count = 0
+        for name in module_names:
+            mod = importlib.import_module(f"cloudinit.config.{name}")
+            frequency = mod.meta["frequency"]
+            # cc_ gets replaced with config- in logs
+            log_name = name.replace("cc_", "config-")
+            # Some modules have been filtered out in /etc/cloud/cloud.cfg,
+            if f"running {log_name}" in log:
+                found_count += 1  # Ensure we're matching on the right text
+                assert f"running {log_name} with frequency {frequency}" in log
+        assert (
+            found_count > 10
+        ), "Not enough modules found in log. Did the log message change?"
+
     def _check_common_metadata(self, data):
         assert data["base64_encoded_keys"] == []
         assert data["merged_cfg"] == "redacted for non-root user"

[blackboxsw]

Additional test if you want it. It's only checking logs, but hopefully our logs aren't lying to us.

diff --git a/tests/integration_tests/modules/test_combined.py b/tests/integration_tests/modules/test_combined.py
index eb45062e..58262ce1 100644
--- a/tests/integration_tests/modules/test_combined.py
+++ b/tests/integration_tests/modules/test_combined.py
@@ -5,12 +5,16 @@ of the test would be unlikely to affect the running of another test using
 the same instance launch. Most independent module coherence tests can go
 here.
 """
+import glob
+import importlib
 import json
 import re
 import uuid
+from pathlib import Path
 
 import pytest
 
+import cloudinit.config
 from tests.integration_tests.clouds import ImageSpecification
 from tests.integration_tests.decorators import retry
 from tests.integration_tests.instances import IntegrationInstance
@@ -223,6 +227,25 @@ class TestCombined:
             class_client.execute("stat -c %N /run/cloud-init/cloud-id")
         )
 
+    def test_run_frequency(self, class_client: IntegrationInstance):
+        log = class_client.read_from_file("/var/log/cloud-init.log")
+        config_dir = Path(cloudinit.config.__file__).parent
+        module_paths = glob.glob(str(config_dir / "cc*.py"))
+        module_names = [Path(x).stem for x in module_paths]
+        found_count = 0
+        for name in module_names:
+            mod = importlib.import_module(f"cloudinit.config.{name}")
+            frequency = mod.meta["frequency"]
+            # cc_ gets replaced with config- in logs
+            log_name = name.replace("cc_", "config-")
+            # Some modules have been filtered out in /etc/cloud/cloud.cfg,
+            if f"running {log_name}" in log:
+                found_count += 1  # Ensure we're matching on the right text
+                assert f"running {log_name} with frequency {frequency}" in log
+        assert (
+            found_count > 10
+        ), "Not enough modules found in log. Did the log message change?"
+
     def _check_common_metadata(self, data):
         assert data["base64_encoded_keys"] == []
         assert data["merged_cfg"] == "redacted for non-root user"

+1 , I was adding something similar to unit tests, but also just a general check that we didn't have anything fall through the cracks with a "None" frequency.
I'll pull in yours as I'd appreciate the full integration test on this, maybe we can suppplement with a no None frequency seen.

[TheRealFalcon]

Here's one for overriding frequency. I put it in tests/integration_tests/modules/test_frequency_override.py:

import pytest

from tests.integration_tests.instances import IntegrationInstance

USER_DATA = """\
#cloud-config
runcmd:
 - echo "hi" >> /var/tmp/hi
"""


@pytest.mark.user_data(USER_DATA)
def test_frequency_override(client: IntegrationInstance):
    # Some pre-checks
    assert (
        "running config-scripts-user with frequency once-per-instance"
        in client.read_from_file("/var/log/cloud-init.log")
    )
    assert client.read_from_file("/var/tmp/hi").strip().count("hi") == 1

    # Change frequency of scripts-user to always
    config = client.read_from_file("/etc/cloud/cloud.cfg")
    new_config = config.replace("- scripts-user", "- [ scripts-user, always ]")
    client.write_to_file("/etc/cloud/cloud.cfg", new_config)

    client.restart()

    # Ensure the script was run again
    assert (
        "running config-scripts-user with frequency always"
        in client.read_from_file("/var/log/cloud-init.log")
    )
    assert client.read_from_file("/var/tmp/hi").strip().count("hi") == 2

[TheRealFalcon]

Thanks! Looks good to me as is. I recently commented another integration test you could add for overriding frequency if you'd like.