Add local run to readme

Author: FurqanHabibi

README.md

@@ -28,7 +28,7 @@ The configuration is a JSON file with the following schema:
       OR
 
       - `"type"`: `"random"`
-      - `"kind"`: `"name"`, `"first_name"`, `"last_name"`, `"user_name"`, `"email"`, `"phone_number"`, etc. See the full list of [randomizer](https://faker.readthedocs.io/en/master/providers.html).
+      - `"kind"`: `"name"`, `"first_name"`, `"last_name"`, `"user_name"`, `"email"`, `"phone_number"`, etc. See the full list of [random providers](https://faker.readthedocs.io/en/master/providers.html).
   - `"drop_constraints"`: list of table constraints to be dropped
 - `"drop_indexes"`: list of index to be dropped
 
@@ -69,3 +69,15 @@ Example:
     ]
 }
 ```
+
+# Running locally
+The tool is meant to be run inside the same network as the RDS subnet that contains the target cluster.
+
+To run the tool locally (for debugging, etc), you need to:
+- Ensure that the temporary RDS cluster is accessible from localhost. See [port-forwarding with session manager](https://docs.aws.amazon.com/systems-manager/latest/userguide/session-manager-working-with-sessions-start.html#sessions-remote-port-forwarding).
+- Specify `--local` flag to set the RDS host target to localhost.
+
+```bash
+poetry install
+poetry run sanitizer --flag
+```

src/sanitizer/cli.py

@@ -26,8 +26,9 @@ def wrapper(*args, **kwargs):
 
 
 @click.command()
+@click.option("--local", is_flag=True, default=False, help="Run locally")
 @async_command
-async def main():
+async def main(local: bool):
     click.echo("#################### Finding latest snapshot ####################")
     snapshot = get_latest_snapshot(settings.rds_cluster_id)
     click.echo(f"Latest snapshot: {snapshot}")
@@ -49,7 +50,7 @@ async def main():
     click.echo("")
 
     click.echo("#################### Sanitizing ####################")
-    await sanitize(temp_cluster, ssm_param)
+    await sanitize(temp_cluster, ssm_param, local)
     click.echo("")
 
     click.echo("#################### Creating sanitized snapshot ####################")

src/sanitizer/sql.py

@@ -59,8 +59,9 @@ async def sanitize_table(table: Table, pool: AsyncConnectionPool) -> int:
         ).rowcount
 
 
-async def sanitize(cluster: DBClusterTypeDef, ssm_param: str) -> None:
-    cluster["Endpoint"] = "localhost"
+async def sanitize(cluster: DBClusterTypeDef, ssm_param: str, local: bool) -> None:
+    if local:
+        cluster["Endpoint"] = "localhost"
     conn_string = (
         f"postgresql://{cluster['MasterUsername']}:{get_password(ssm_param)}"
         f"@{cluster['Endpoint']}:{cluster['Port']}"