add stop_instances_by_incremental_steps action to ec2

Signed-off-by: Sylvain Hellegouarch <[email protected]>

Author: Lawouach

CHANGELOG.md

@@ -2,7 +2,15 @@
 
 ## [Unreleased][]
 
-[Unreleased]: https://github.com/chaostoolkit-incubator/chaostoolkit-aws/compare/0.28.0...HEAD
+[Unreleased]: https://github.com/chaostoolkit-incubator/chaostoolkit-aws/compare/0.29.0...HEAD
+
+## [0.29.0][] - 2023-12-10
+
+[0.29.0]: https://github.com/chaostoolkit-incubator/chaostoolkit-aws/compare/0.28.0...0.29.0
+
+### Added
+
+- Action `stop_instances_by_incremental_steps` in the ec2 package
 
 ## [0.28.0][] - 2023-12-01
 

chaosaws/__init__.py

@@ -16,7 +16,7 @@
 from chaoslib.types import Configuration, DiscoveredActivities, Discovery, Secrets
 from logzero import logger
 
-__version__ = "0.28.0"
+__version__ = "0.29.0"
 __all__ = ["__version__", "discover", "aws_client", "signed_api_call"]
 
 
@@ -288,3 +288,18 @@ def time_to_datetime(
         delta = 60 * 60 * 24
 
     return offset - timedelta(seconds=duration * delta)
+
+
+def convert_tags(tags: Union[str, Dict[str, str]]) -> Dict[str, str]:
+    """
+    Convert a `k=v,x=y` string into a dictionary
+    """
+    if isinstance(tags, dict):
+        return tags
+
+    result = {}
+    for t in tags.split(","):
+        k, v = t.split("=", 1)
+        result[k] = v
+
+    return result

chaosaws/ec2/actions.py

@@ -1,4 +1,5 @@
 import random
+import time
 from collections import defaultdict
 from copy import deepcopy
 from typing import Any, Dict, List, Union
@@ -9,7 +10,7 @@
 from chaoslib.types import Configuration, Secrets
 from logzero import logger
 
-from chaosaws import aws_client
+from chaosaws import aws_client, convert_tags
 from chaosaws.types import AWSResponse
 
 __all__ = [
@@ -21,6 +22,7 @@
     "restart_instances",
     "detach_random_volume",
     "attach_volume",
+    "stop_instances_by_incremental_steps",
 ]
 
 
@@ -423,9 +425,77 @@ def attach_volume(
     return results
 
 
+def stop_instances_by_incremental_steps(
+    volume: int,
+    step_quantity: int,
+    step_duration: int,
+    az: str = None,
+    tags: Union[str, Dict[str, Any]] = None,
+    force: bool = False,
+    configuration: Configuration = None,
+    secrets: Secrets = None,
+) -> List[AWSResponse]:
+    """
+    Stop a volume of instances incrementally by steps.
+
+    The steps are using two dimensions, the duration between two iterations
+    and the number of instances to stop on each iteration.
+
+    The `tags` can be specified as a key=value pair dictionary or a comma
+    separated list of k=v pairs. They are good to be set when you want to
+    target only a certain subset of instances. Likewise for the
+    availability-zone.
+    """
+    client = aws_client("ec2", configuration, secrets)
+
+    filters = []
+
+    tags = convert_tags(tags) if tags else []
+
+    if tags:
+        filters.append(tags)
+
+    if az:
+        filters.append({"Name": "availability-zone", "Values": [az]})
+
+    instances = list_instances_by_type(filters, client)
+
+    if not instances:
+        raise FailedActivity(f"No instances in availability zone: {az}")
+
+    logger.debug(
+        "Picked EC2 instances '{}' from AZ '{}' to be stopped".format(
+            str(instances), az
+        )
+    )
+
+    total = len(instances)
+    count = round(total * volume / 100)
+    target_instances = random.sample(instances, count)
+
+    responses = []
+    while target_instances:
+        stop_these_instances_now = target_instances[:step_quantity]
+        target_instances = target_instances[step_quantity:]
+
+        responses.extend(
+            stop_instances_any_type(
+                instance_types=stop_these_instances_now, force=force, client=client
+            )
+        )
+
+        pause_for_a_while(step_duration)
+
+    return responses
+
+
 ###############################################################################
 # Private functions
 ###############################################################################
+def pause_for_a_while(duration: int) -> None:
+    time.sleep(float(duration))
+
+
 def list_instances_by_type(
     filters: List[Dict[str, Any]], client: boto3.client
 ) -> Dict[str, Any]:

chaosaws/fis/actions.py

@@ -4,7 +4,7 @@
 from chaoslib.types import Configuration, Secrets
 from logzero import logger
 
-from chaosaws import aws_client
+from chaosaws import aws_client, convert_tags
 from chaosaws.types import AWSResponse
 
 __all__ = [
@@ -157,7 +157,6 @@ def stop_experiments_by_tags(
 
     stopped = []
     for x in experiments["experiments"]:
-        print(x)
         try:
             if x["tags"] == tags:
                 status = x["state"]["status"]
@@ -483,21 +482,3 @@ def start_availability_zone_power_interruption_scenario(
         return fis_client.start_experiment(**params)
     except Exception as ex:
         raise FailedActivity(f"Start Experiment failed, reason was: {ex}")
-
-
-###############################################################################
-# Private functions
-###############################################################################
-def convert_tags(tags: Union[str, Dict[str, str]]) -> Dict[str, str]:
-    """
-    Convert a `k=v,x=y` string into a dictionary
-    """
-    if isinstance(tags, dict):
-        return tags
-
-    result = {}
-    for t in tags.split(","):
-        k, v = t.split("=", 1)
-        result[k] = v
-
-    return result