Image resizer lambda function triggered by S3 example Guide on uploading to AWS zip the file zip -r function.zip . run the command for creating a new function if the function doesn't exist yet run command for updating if the function already exist create function aws lambda create-function --function-name create-thumbnail --zip-file fileb://function.zip --profile qhkm --region ap-northeast-1 --role arn:aws:iam::3213213213123:role/lambda-s3-role --timeout 10 --memory-size 1024 --runtime nodejs12.x --handler index.handler update function aws lambda update-function-code --function-name create-thumbnail --zip-file fileb://function.zip --profile qhkm --region ap-northeast-1