Fix infinite recursion in GCE provider

Providers have pools have a provider have pools...

This fix mirrors the approach from the AWS driver.

Change-Id: I33be1ba7c604754139566642ca6a863304a74e73
(cherry picked from commit 559e3098d1)

nodepool/driver/gce/config.py

@@ -54,6 +54,8 @@ class ProviderCloudImage(ConfigValue):
 
 
 class ProviderLabel(ConfigValue):
+    ignore_equality = ['pool']
+
     def __init__(self):
         self.name = None
         self.cloud_image = None
@@ -79,6 +81,8 @@ class ProviderLabel(ConfigValue):
 
 
 class ProviderPool(ConfigPool):
+    ignore_equality = ['provider']
+
     def __init__(self):
         self.name = None
         self.host_key_checking = True

nodepool/tests/unit/test_driver_gce.py

@@ -18,6 +18,7 @@ import os
 import tempfile
 import time
 from unittest.mock import patch
+from functools import wraps
 
 import yaml
 
@@ -234,9 +235,9 @@ class TestDriverGce(tests.DBTestCase):
             except Exception:
                 pass
 
-    def _test_gce_machine(self, label,
-                          is_valid_config=True,
-                          host_key_checking=True):
+    def _test_with_pool(the_test):
+        @wraps(the_test)
+        def wrapper(self, *args, **kwargs):
             self.patch(googleapiclient, 'discovery', GCloudEmulator())
 
             conf_template = os.path.join(
@@ -253,13 +254,24 @@ class TestDriverGce(tests.DBTestCase):
                 'cert': self.zookeeper_cert,
                 'key': self.zookeeper_key,
             }
-
             with tempfile.NamedTemporaryFile() as tf:
                 tf.write(yaml.safe_dump(
                     raw_config, default_flow_style=False).encode('utf-8'))
                 tf.flush()
                 configfile = self.setup_config(tf.name)
                 pool = self.useNodepool(configfile, watermark_sleep=1)
+                the_test(self, pool, *args, **kwargs)
+        return wrapper
+
+    @_test_with_pool
+    def test_gce_reconfigure(self, pool):
+        pool.updateConfig()
+        pool.updateConfig()
+
+    @_test_with_pool
+    def _test_gce_machine(self, pool, label,
+                          is_valid_config=True,
+                          host_key_checking=True):
         pool.start()
 
         self._wait_for_provider(pool, 'gcloud-provider')