From 9defb38c9a484eed620a44ab6b79f8071dda5578 Mon Sep 17 00:00:00 2001
From: Siyuan <suquark@gmail.com>
Date: Mon, 24 Jul 2023 23:57:46 -0700
Subject: [PATCH] fix comments

---
 sky/provision/__init__.py     |  4 +++
 sky/provision/aws/instance.py | 48 ++++++++++++++++-------------------
 2 files changed, 26 insertions(+), 26 deletions(-)

diff --git a/sky/provision/__init__.py b/sky/provision/__init__.py
index e8af44f500c..3b22c1f124c 100644
--- a/sky/provision/__init__.py
+++ b/sky/provision/__init__.py
@@ -8,6 +8,7 @@
 import functools
 import importlib
 import inspect
+
 from sky import status_lib
 
 
@@ -46,6 +47,9 @@ def query_instances(
     """Query instances.
 
     Returns a dictionary of instance IDs and status.
+
+    A None status means the instance is marked as "terminated"
+    or "terminating".
     """
     raise NotImplementedError
 
diff --git a/sky/provision/aws/instance.py b/sky/provision/aws/instance.py
index 270d6bfbb04..5f523e7a5a4 100644
--- a/sky/provision/aws/instance.py
+++ b/sky/provision/aws/instance.py
@@ -2,6 +2,7 @@
 from typing import Dict, List, Any, Optional
 
 from botocore import config
+
 from sky.adaptors import aws
 from sky import status_lib
 
@@ -11,6 +12,20 @@
 TAG_RAY_NODE_KIND = 'ray-node-type'
 
 
+def _default_ec2_resource(region: str) -> Any:
+    return aws.resource(
+        'ec2',
+        region_name=region,
+        config=config.Config(retries={'max_attempts': BOTO_MAX_RETRIES}))
+
+
+def _cluster_name_filter(cluster_name: str) -> List[Dict[str, Any]]:
+    return [{
+        'Name': f'tag:{TAG_RAY_CLUSTER_NAME}',
+        'Values': [cluster_name],
+    }]
+
+
 def _filter_instances(ec2, filters: List[Dict[str, Any]],
                       included_instances: Optional[List[str]],
                       excluded_instances: Optional[List[str]]):
@@ -33,18 +48,11 @@ def query_instances(
     cluster_name: str,
     provider_config: Optional[Dict[str, Any]] = None,
 ) -> Dict[str, Optional[status_lib.ClusterStatus]]:
+    """See sky/provision/__init__.py"""
     assert provider_config is not None, (cluster_name, provider_config)
     region = provider_config['region']
-    ec2 = aws.resource(
-        'ec2',
-        region_name=region,
-        config=config.Config(retries={'max_attempts': BOTO_MAX_RETRIES}))
-    filters = [
-        {
-            'Name': f'tag:{TAG_RAY_CLUSTER_NAME}',
-            'Values': [cluster_name],
-        },
-    ]
+    ec2 = _default_ec2_resource(region)
+    filters = _cluster_name_filter(cluster_name)
     instances = ec2.instances.filter(Filters=filters)
     status_map = {
         'pending': status_lib.ClusterStatus.INIT,
@@ -71,19 +79,13 @@ def stop_instances(
     """See sky/provision/__init__.py"""
     assert provider_config is not None, (cluster_name, provider_config)
     region = provider_config['region']
-    ec2 = aws.resource(
-        'ec2',
-        region_name=region,
-        config=config.Config(retries={'max_attempts': BOTO_MAX_RETRIES}))
+    ec2 = _default_ec2_resource(region)
     filters = [
         {
             'Name': 'instance-state-name',
             'Values': ['pending', 'running'],
         },
-        {
-            'Name': f'tag:{TAG_RAY_CLUSTER_NAME}',
-            'Values': [cluster_name],
-        },
+        *_cluster_name_filter(cluster_name),
     ]
     if worker_only:
         filters.append({
@@ -108,20 +110,14 @@ def terminate_instances(
     """See sky/provision/__init__.py"""
     assert provider_config is not None, (cluster_name, provider_config)
     region = provider_config['region']
-    ec2 = aws.resource(
-        'ec2',
-        region_name=region,
-        config=config.Config(retries={'max_attempts': BOTO_MAX_RETRIES}))
+    ec2 = _default_ec2_resource(region)
     filters = [
         {
             'Name': 'instance-state-name',
             # exclude 'shutting-down' or 'terminated' states
             'Values': ['pending', 'running', 'stopping', 'stopped'],
         },
-        {
-            'Name': f'tag:{TAG_RAY_CLUSTER_NAME}',
-            'Values': [cluster_name],
-        },
+        *_cluster_name_filter(cluster_name),
     ]
     if worker_only:
         filters.append({