Configuration files with .json extension might be copied before sent it to s3.
.key (googleCloud) or .json config files might be copied after compile code process. Otherwise Lambda returns a module error b/c file isn't there.
Use example -------
const visionApi = googleVision({ projectId: 'awesome-project-168122', keyFilename: './my-service-accout.json', });
Error example -----------
Unable to import module 'handler': Error
at Function.Module._resolveFilename (module.js:469:15)
at Function.Module._load (module.js:417:25)
at Module.require (module.js:497:17)
at require (internal/module.js:20:19)
at Object.
My bad the issue described above is related to google vision library. But it still being a good idea copy those .json files to allow configuration files.
I fixed it temporally using this solution here: https://stackoverflow.com/questions/40032758/aws-lambda-w-google-vision-api-throwing-pem-read-biono-start-line-or-errnoen