GCE: add use-internal-ip option

This adds an option to the GCE driver to tell nodepool to use the
private ip address even when an external one is provided.

Also add a missing schema entry for rate-limit.

Change-Id: Ib15bdc76fe500dc0fe6bb98f870514e9e157c1a5

doc/source/configuration.rst

@@ -2007,6 +2007,12 @@ section of the configuration.
          booted. This might be needed if nodepool-launcher and the nodes it
          launches are on different networks.  The default value is True.
 
+      .. attr:: use-internal-ip
+         :default: False
+
+         Whether to access the instance with the internal or external IP
+         address.
+
       .. attr:: labels
          :type: list
 

nodepool/driver/gce/config.py

@@ -80,6 +80,7 @@ class ProviderPool(ConfigPool):
     def __init__(self):
         self.name = None
         self.host_key_checking = True
+        self.use_internal_ip = False
         self.labels = None
         # The ProviderConfig object that owns this pool.
         self.provider = None
@@ -94,6 +95,8 @@ class ProviderPool(ConfigPool):
 
         self.host_key_checking = bool(
             pool_config.get('host-key-checking', True))
+        self.use_internal_ip = bool(
+            pool_config.get('use-internal-ip', False))
 
         for label in pool_config.get('labels', []):
             pl = ProviderLabel()
@@ -124,6 +127,7 @@ class ProviderPool(ConfigPool):
             return (super().__eq__(other)
                     and other.name == self.name
                     and other.host_key_checking == self.host_key_checking
+                    and other.use_internal_ip == self.use_internal_ip
                     and other.labels == self.labels)
         return False
 
@@ -218,6 +222,7 @@ class GCEProviderConfig(ProviderConfig):
         pool.update({
             v.Required('name'): str,
             v.Required('labels'): [pool_label],
+            'use-internal-ip': bool,
         })
 
         provider_cloud_images = {
@@ -239,6 +244,7 @@ class GCEProviderConfig(ProviderConfig):
             'cloud-images': [provider_cloud_images],
             'boot-timeout': int,
             'launch-retries': int,
+            'rate-limit': int,
         })
         return v.Schema(provider)
 

nodepool/driver/simple.py

@@ -106,7 +106,10 @@ class SimpleTaskManagerLauncher(NodeLauncher):
 
         self.log.debug("Created instance %s", repr(instance))
 
-        server_ip = instance.interface_ip
+        if self.pool.use_internal_ip:
+            server_ip = instance.private_ipv4
+        else:
+            server_ip = instance.interface_ip
 
         self.node.connection_port = self.label.cloud_image.connection_port
         self.node.connection_type = self.label.cloud_image.connection_type