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Hi @GowsikChandran !
Please remove the - LAMBDA_DOCKER_NETWORK=backend_hub-net section of your docker compose - LocalStack will automatically detect the right network, and the name has to include the docker compose project name itself as well - docker compose will usually prefix the network name with it.
In general, please take a look at our sample docker compose: https://github.com/localstack/localstack/blob/master/docker-compose.yml and try this file to see if this resolves your issues, before adding back some of the modifications you made.

Hi @dfangl
thank you for the response :)

I updated the docker compose

services:
localstack:
image: localstack/localstack:stable
container_name: container-localstack
restart: unless-stopped
ports:
- "127.0.0.1:4566:4566" # LocalStack Gateway
- "127.0.0.1:4510-4559:4510-4559" # external services port range
environment:
- SERVICES=iam,lambda,apigateway,cloudformation,secretsmanager,dynamodb
- DEFAULT_REGION=us-east-1
- DEBUG=1
- PERSISTENCE=1
- LAMBDA_KEEPALIVE_MS=0
- LAMBDA_RUNTIME_ENVIRONMENT_TIMEOUT=120
volumes:
- localstack_data:/var/lib/localstack
- /var/run/docker.sock:/var/run/docker.sock
networks:
nexhub-net:

I am invoking the function via postman
http://kxfdkcnexl.execute-api.localhost.localstack.cloud:4566/local/test

the function and the hot-reload normally works but it not working if I add boto3 to my code
client = boto3.client(
"lambda",
endpoint_url=os.getenv("AWS_ENDPOINT_URL"),
aws_access_key_id="test",
aws_secret_access_key="test",
region_name=os.getenv("AWS_REGION")
)
result = client.list_functions()

the container restarts 4 times and stops. below is the log of the last restart.

container-localstack | 2025-03-31T10:36:24.320 DEBUG --- [et.reactor-4] l.s.l.i.version_manager : Got an invocation for function arn:aws:lambda:us-east-1:000000000000:function:proxy-function:$LATEST with request_id 4cfb498e-628a-41de-85f9-63006ba3adff
container-localstack | 2025-03-31T10:36:24.321 DEBUG --- [et.reactor-4] l.s.l.i.assignment : Starting new environment
container-localstack | 2025-03-31T10:36:24.327 DEBUG --- [et.reactor-4] l.s.l.i.docker_runtime_exe : Assigning container name of container-localstack-lambda-proxy-function-3a6023de14a29d118adedfd6ddc11532 to executor 3a6023de14a29d118adedfd6ddc11532
container-localstack | 2025-03-31T10:36:24.344 DEBUG --- [et.reactor-4] l.u.c.docker_sdk_client : Creating container with attributes: {'self': <localstack.utils.container_utils.docker_sdk_client.SdkDockerClient object at 0x7fe23efed810>, 'image_name': 'public.ecr.aws/lambda/python:3.12', 'name': 'container-localstack-lambda-proxy-function-3a6023de14a29d118adedfd6ddc11532', 'entrypoint': '/var/rapid/init', 'remove': False, 'interactive': False, 'tty': False, 'detach': False, 'command': None, 'volumes': [VolumeBind(host_dir='D:/vscode-projects/nexiam/nexiam-backend/serverless/nexhub', container_dir='/var/task', read_only=True)], 'ports': <PortMappings: {}>, 'exposed_ports': [], 'env_vars': {'AWS_DEFAULT_REGION': 'us-east-1', 'AWS_REGION': 'us-east-1', 'AWS_LAMBDA_FUNCTION_NAME': 'proxy-function', 'AWS_LAMBDA_FUNCTION_MEMORY_SIZE': 512, 'AWS_LAMBDA_FUNCTION_VERSION': '$LATEST', 'AWS_LAMBDA_INITIALIZATION_TYPE': 'on-demand', 'AWS_LAMBDA_LOG_GROUP_NAME': '/aws/lambda/proxy-function', 'AWS_LAMBDA_LOG_STREAM_NAME': '2025/03/31/[$LATEST]3a6023de14a29d118adedfd6ddc11532', 'AWS_ACCESS_KEY_ID': 'LSIAQAAAAAAAOUTP6XD6', 'AWS_SECRET_ACCESS_KEY': 'UIHtXxkgUkkncxlNrqXksZJJ+nSxJYgKVPcTkfwy', 'AWS_SESSION_TOKEN': 'FQoGZXIvYXdzEBYaDCMs0L2RzVTwrh+jxz6ElQbwrOI/B0u7nbNNxM4M6MWmXK14ANfZTOh7vuwEQ78ctgneZbrbBLYuW0mym2qyAf17cBeFV27kbBgjbv+Aj9/MZHwHMeZZ/xwp/jjj0iTjfW3AYqFCnscFJ0abwFPv0gqKQqWT5Q+SVJTw9muTVRxWcIzJAU98Kxs/IlwIYLddcKAzHPuu+U9cdhXRPxOcI0fcT+TPNXGeyXHBSw6h0qNOkqoKtdASu1c7ltfOTtyoBWkL7bBRuQe8IKQNr5oe/cqw1zs3/ymEjHng07dDrLwn8O9XMrliO0wQGjvl7pr6aFrF+5YiXvQhgY2U588=', 'LAMBDA_TASK_ROOT': '/var/task', 'LAMBDA_RUNTIME_DIR': '/var/runtime', 'AWS_XRAY_CONTEXT_MISSING': 'LOG_ERROR', 'AWS_XRAY_DAEMON_ADDRESS': '127.0.0.1:2000', '_AWS_XRAY_DAEMON_PORT': '2000', '_AWS_XRAY_DAEMON_ADDRESS': '127.0.0.1', 'TZ': ':UTC', 'AWS_LAMBDA_FUNCTION_TIMEOUT': 600, 'LOCALSTACK_HOSTNAME': '172.18.0.3', 'EDGE_PORT': '4566', 'LOCALSTACK_RUNTIME_ID': '3a6023de14a29d118adedfd6ddc11532', 'LOCALSTACK_RUNTIME_ENDPOINT': 'http://172.18.0.3:4566/_localstack_lambda/3a6023de14a29d118adedfd6ddc11532', 'LOCALSTACK_FUNCTION_ACCOUNT_ID': '000000000000', 'AWS_ENDPOINT_URL': 'http://172.18.0.3:4566', '_HANDLER': 'main.lambda_handler', 'AWS_EXECUTION_ENV': 'AWS_Lambda_rapid', 'PYTHONPATH': '/var/task/deps:$PYTHONPATH', 'LOCALSTACK_MAX_PAYLOAD_SIZE': 6291556, 'LOCALSTACK_HOT_RELOADING_PATHS': '/var/task', 'LOCALSTACK_CHMOD_PATHS': '[{"path": "/tmp", "mode": "0700"}]'}, 'user': None, 'cap_add': None, 'cap_drop': None, 'security_opt': None, 'network': 'nexiam-backend_nexhub-net', 'dns': '172.18.0.3', 'additional_flags': '', 'workdir': None, 'privileged': False, 'labels': None, 'platform': 'linux/amd64', 'ulimits': None, 'init': None, 'log_config': None}
container-localstack | 2025-03-31T10:36:24.509 DEBUG --- [et.reactor-4] l.u.c.docker_sdk_client : Copying file /usr/lib/localstack/lambda-runtime/v0.1.32-pre/x86_64/. into container-localstack-lambda-proxy-function-3a6023de14a29d118adedfd6ddc11532:/
container-localstack | 2025-03-31T10:36:27.026 DEBUG --- [et.reactor-4] l.u.c.docker_sdk_client : Starting container container-localstack-lambda-proxy-function-3a6023de14a29d118adedfd6ddc11532
container-localstack | 2025-03-31T10:36:29.352 DEBUG --- [et.reactor-4] l.u.c.container_client : Getting ipv4 address for container container-localstack-lambda-proxy-function-3a6023de14a29d118adedfd6ddc11532 in network nexiam-backend_nexhub-net.
container-localstack | 2025-03-31T10:37:18.954 WARN --- [ Thread-85] l.s.l.i.execution_environm : Execution environment 92c9eb604159c0c4cfdfb660a25a683c for function arn:aws:lambda:us-east-1:000000000000:function:proxy-function:$LATEST timed out during startup. Check for errors during the startup of your Lambda function and consider increasing the startup timeout via LAMBDA_RUNTIME_ENVIRONMENT_TIMEOUT.
container-localstack | 2025-03-31T10:37:19.029 DEBUG --- [ Thread-85] l.s.l.i.execution_environm : Logs from the execution environment 92c9eb604159c0c4cfdfb660a25a683c after startup timeout:
container-localstack | [lambda 92c9eb604159c0c4cfdfb660a25a683c]
container-localstack | 2025-03-31T10:37:19.029 DEBUG --- [ Thread-85] l.u.c.docker_sdk_client : Stopping container: container-localstack-lambda-proxy-function-92c9eb604159c0c4cfdfb660a25a683c
container-localstack | 2025-03-31T10:37:20.432 DEBUG --- [ Thread-85] l.u.c.docker_sdk_client : Removing container: container-localstack-lambda-proxy-function-92c9eb604159c0c4cfdfb660a25a683c
container-localstack | 2025-03-31T10:37:22.087 WARN --- [et.reactor-1] l.s.a.n.e.integrations.aws : Unexpected exception during integration invocation: 'Read timeout on endpoint URL: "http://localhost:4566/2015-03-31/functions/arn%3Aaws%3Alambda%3Aus-east-1%3A000000000000%3Afunction%3Aproxy-function/invocations"'
container-localstack | 2025-03-31T10:37:22.088 INFO --- [et.reactor-1] l.s.a.n.e.h.gateway_except : Error raised during invocation: INTEGRATION_FAILURE
container-localstack | 2025-03-31T10:37:22.091 INFO --- [et.reactor-1] localstack.request.http : GET /local/test => 502

this is my aws config file

[default]
region=us-east-1
output=json
endpoint_url = http://localhost.localstack.cloud:4566

this is my aws credentials file

[default]
aws_access_key_id=test
aws_secret_access_key=test

This new code, do you add it on the module level to your python function, or within the handler itself? If the former, can you try it within the handler, this should make the error more obvious.

Hi @dfangl

I tried creating boto3 client outside and also tried inside the handler but I get the same error.

LAMBDA_RUNTIME_ENVIRONMENT_TIMEOUT if I add the boto3 code, (i also increased the timeout of LAMBDA_RUNTIME_ENVIRONMENT_TIMEOUT and lambda function)

if I remove the boto3 code everything is fine

Hi @GowsikChandran , sorry for the delayed response.
Does the same thing happen without hot reloading, but including the boto3 code? Could you share a (stripped, but confirmed not working) complete code example of the lambda deployed?
Please also share the LocalStack version printed at startup!

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