Lambda functions and buckets
I created 2 S3 Buckets:
sourcebucketname
destinationbucketname
I then made a Lambda function and chose to “author from scratch”
I created a role name and made a Lambda role.
I added an event trigger and allowed for recursive incovation which would prevent failures.
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I uploaded a test file into the first S3 bucket and then did some light debugging, by going to CloudWatch>Logs>
I tried a little experiment of my own. Under S3 Bucket properties, I enabled versioning. Before doing so, when I uploaded 2 test files with the same name, the older one was replaced. I suppose I expected a “do you want to overwrite this file?” message such as in Windows. This proves why versioning and object naming is so important. You can overwrite a file without realizing it. Versioning allowed me to see the previous copy of the object:
After deploying the function and uploaded around 20 test files, I had several CloudWatch logs to draw from and analyze the process.
I had an error from when I mistakenly placed bucket names in wrong line of code:
I was able to also determine that in the Lamba function, I could test by naming a specific filename under Key under Object and selecting a S3 Put template!
“object”: {
“key”: “filename.file”,
“size”: 1024,
