aws-sam-cli: Bug: Invoking a lambda function is giving me an error 'cannot find module' even though module exists

After building and starting the local sam server, I’m noticing after I run my lambda GetBlocksByDateRangeFunction, I get this error in the console.

Invalid lambda response received: Invalid API Gateway Response Keys: {'trace', 'errorMessage', 'errorType'} in {'errorType': 'Runtime.ImportModuleError', 'errorMessage': "Error: Cannot find
module 'something'\nRequire stack:\n- /var/runtime/index.mjs", 'trace': ["Runtime.ImportModuleError: Error: Cannot find module 'something'", 'Require stack:', '- /var/runtime/index.mjs', '
at _loadUserApp (file:///var/runtime/index.mjs:997:17)', '    at async UserFunction.js.module.exports.load (file:///var/runtime/index.mjs:1032:21)', '    at async start
(file:///var/runtime/index.mjs:1195:23)', '    at async file:///var/runtime/index.mjs:1201:1']}

Steps to reproduce:

I’m not sure how I got this behavior to happen.

Observed result:

2023-06-25 11:58:45,415 | Constructed Event 1.0 to invoke Lambda. Event: {'version': '1.0', 'httpMethod': 'GET', 'body': None, 'resource': '/kevin', 'requestContext': {'resourceId': '123456',
'apiId': '1234567890', 'resourcePath': '/kevin', 'httpMethod': 'GET', 'requestId': '04e1e7ee-a920-462e-ac8d-3589db2ff535', 'accountId': '123456789012', 'stage': 'Prod', 'identity': {'apiKey':
None, 'userArn': None, 'cognitoAuthenticationType': None, 'caller': None, 'userAgent': 'Custom User Agent String', 'user': None, 'cognitoIdentityPoolId': None, 'cognitoAuthenticationProvider':
None, 'sourceIp': '127.0.0.1', 'accountId': None}, 'extendedRequestId': None, 'path': '/kevin', 'protocol': 'HTTP/1.1', 'domainName': '127.0.0.1:3001', 'requestTimeEpoch': 1687719488,
'requestTime': '25/Jun/2023:18:58:08 +0000'}, 'queryStringParameters': None, 'multiValueQueryStringParameters': None, 'headers': {'User-Agent': 'PostmanRuntime/7.32.3', 'Accept': '*/*',
'Postman-Token': '6f0a0ea9-75de-4839-a840-947f37c83019', 'Host': '127.0.0.1:3001', 'Accept-Encoding': 'gzip, deflate, br', 'Connection': 'keep-alive', 'X-Forwarded-Proto': 'http',
'X-Forwarded-Port': '3001'}, 'multiValueHeaders': {'User-Agent': ['PostmanRuntime/7.32.3'], 'Accept': ['*/*'], 'Postman-Token': ['6f0a0ea9-75de-4839-a840-947f37c83019'], 'Host':
['127.0.0.1:3001'], 'Accept-Encoding': ['gzip, deflate, br'], 'Connection': ['keep-alive'], 'X-Forwarded-Proto': ['http'], 'X-Forwarded-Port': ['3001']}, 'pathParameters': None,
'stageVariables': None, 'path': '/kevin', 'isBase64Encoded': False}
2023-06-25 11:58:45,419 | Found one Lambda function with name 'GetBlocksByDateRangeFunction'
2023-06-25 11:58:45,424 | Invoking src/handlers/something.somethingHandler (nodejs18.x)
2023-06-25 11:58:45,425 | No environment variables found for function 'GetBlocksByDateRangeFunction'
2023-06-25 11:58:45,426 | Resolving code path. Cwd=/Users/kirkchu/pairup/ourtracks-node-api/.aws-sam/build,
CodeUri=/Users/kirkchu/pairup/ourtracks-node-api/.aws-sam/build/GetBlocksByDateRangeFunction
2023-06-25 11:58:45,427 | Resolved absolute path to code is /Users/kirkchu/pairup/ourtracks-node-api/.aws-sam/build/GetBlocksByDateRangeFunction
2023-06-25 11:58:45,427 | Code /Users/kirkchu/pairup/ourtracks-node-api/.aws-sam/build/GetBlocksByDateRangeFunction is not a zip/jar file
2023-06-25 11:58:45,465 | Using local image: public.ecr.aws/lambda/nodejs:18-rapid-x86_64.

2023-06-25 11:58:45,466 | Mounting /Users/kirkchu/pairup/ourtracks-node-api/.aws-sam/build/GetBlocksByDateRangeFunction as /var/task:ro,delegated, inside runtime container
2023-06-25 11:58:46,369 | Starting a timer for 3 seconds for function 'GetBlocksByDateRangeFunction'
START RequestId: 56b06cbc-5a48-4570-886f-f9e589e8b906 Version: $LATEST
2023-06-25T18:58:46.658Z	undefined	ERROR	Uncaught Exception 	{"errorType":"Runtime.ImportModuleError","errorMessage":"Error: Cannot find module 'something'\nRequire stack:\n- /var/runtime/index.mjs","stack":["Runtime.ImportModuleError: Error: Cannot find module 'something'","Require stack:","- /var/runtime/index.mjs","    at _loadUserApp (file:///var/runtime/index.mjs:997:17)","    at async UserFunction.js.module.exports.load (file:///var/runtime/index.mjs:1032:21)","    at async start (file:///var/runtime/index.mjs:1195:23)","    at async file:///var/runtime/index.mjs:1201:1"]}
25 Jun 2023 18:58:46,687 [ERROR] (rapid) Init failed error=Runtime exited with error: exit status 129 InvokeID=
2023-06-25T18:58:46.957Z	undefined	ERROR	Uncaught Exception 	{"errorType":"Runtime.ImportModuleError","errorMessage":"Error: Cannot find module 'something'\nRequire stack:\n- /var/runtime/index.mjs","stack":["Runtime.ImportModuleError: Error: Cannot find module 'something'","Require stack:","- /var/runtime/index.mjs","    at _loadUserApp (file:///var/runtime/index.mjs:997:17)","    at async UserFunction.js.module.exports.load (file:///var/runtime/index.mjs:1032:21)","    at async start (file:///var/runtime/index.mjs:1195:23)","    at async file:///var/runtime/index.mjs:1201:1"]}
END RequestId: 191afcfa-7165-4e0d-a437-efa1c55904c9
REPORT RequestId: 191afcfa-7165-4e0d-a437-efa1c55904c9	Init Duration: 0.94 ms	Duration: 567.76 ms	Billed Duration: 568 ms	Memory Size: 128 MB	Max Memory Used: 128 MB
2023-06-25 11:58:47,270 | Cleaning all decompressed code dirs
2023-06-25 11:58:47,272 | Lambda returned empty body!
2023-06-25 11:58:47,273 | Invalid lambda response received: Invalid API Gateway Response Keys: {'errorType', 'trace', 'errorMessage'} in {'errorType': 'Runtime.ImportModuleError',
'errorMessage': "Error: Cannot find module 'something'\nRequire stack:\n- /var/runtime/index.mjs", 'trace': ["Runtime.ImportModuleError: Error: Cannot find module 'something'", 'Require
stack:', '- /var/runtime/index.mjs', '    at _loadUserApp (file:///var/runtime/index.mjs:997:17)', '    at async UserFunction.js.module.exports.load (file:///var/runtime/index.mjs:1032:21)', '
at async start (file:///var/runtime/index.mjs:1195:23)', '    at async file:///var/runtime/index.mjs:1201:1']}

Expected result:

I’m expecting it to not return an error and not to say Cannot Find Module since the module does exist.

Additional environment details (Ex: Windows, Mac, Amazon Linux etc)

Mac

1. OS: MacOS Big Sur
2. sam --version: SAM CLI, version 1.88.0
3. AWS region: us-west-2

# Paste the output of `sam --info` here

{
  "version": "1.88.0",
  "system": {
    "python": "3.11.4",
    "os": "macOS-11.2.2-x86_64-i386-64bit"
  },
  "additional_dependencies": {
    "docker_engine": "20.10.23",
    "aws_cdk": "Not available",
    "terraform": "Not available"
  },
  "available_beta_feature_env_vars": [
    "SAM_CLI_BETA_FEATURES",
    "SAM_CLI_BETA_BUILD_PERFORMANCE",
    "SAM_CLI_BETA_TERRAFORM_SUPPORT",
    "SAM_CLI_BETA_RUST_CARGO_LAMBDA"
  ]
}```

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