AWS Lambda doesn't read from S3

Question

I have an AWS Lambda function which fully works when tested locally using ATOM, within this it reads and writes to my s3 bucket. However when I upload the function to Lambda it doesn't seem to have access to S3. Whenever I try to read from S3 it simply times out after 3 minutes, even on simple requests like listing buckets.

I have increased the access of "Lambda Basic Execution" to have full admin access, and it still doesn't work.

Any ideas would be greatly appreciated.

There's not much information there to go on. How does the Lambda talk to S3 http or SDK calls? Can you provide more information, like a code snippet, configuration of your bucket, how you are deploying the Lambda, etc. — Matt D, Oct 04 '18 at 12:53
Did you specify all required variables in Environment variables (aws concole -> lambda service->pick a function->configuration> Environment variables)? — Nikolay Vetrov, Oct 04 '18 at 22:21

score 0 · Answer 1 · answered Oct 05 '18 at 07:58

According to information provided you have troubles with communication between deployed to server lambda and S3. When running on the local machine, where you have direct access to S3, there is no problem, because it is not isolated environment as in VPC.

Please check your network configuration (especially when lambda runs in VPC, for tests purposes you can disable that in AWS console -> Lambda -> yourLambdaFunction -> Network -> choose No VPC). Image below shows the lambda config for those tests: Lambda console no VPC config

It was mentioned before. Answers included should solve your problem:

Lambda Timeout while communicating with S3

Please let us know if it helps.

AWS Lambda doesn't read from S3

1 Answers1