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Comment by nicksergeant | Hacker News Reader

But, if you have more than one Lambda working on a single S3 bucket, for example, it's possible to trigger executions infinitely.

Edit: my mistake - you still can't have multiple lambdas operating on a single S3 bucket. I had triggered an infinite loop by manipulating files in the same bucket that it was triggered on (triggering another execution, infinitely).

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Last time I checked, you could only have one Lambda function attached to bucket events at a time.

Yep, but if your lambda creates a new file in that bucket, it'll get called again (as an example).

Edit: realized my mistake in the wording of my comment above - _how_ I made the infinite loop had escaped me for a moment.

I believe when you upload your code it will throw an error that your source and destination bucket are the same, which will prevent this type of looping.

This wasn't the case when I was uploading mine, but maybe they've done some sort of smart checking on the execution role (it'd be pretty hard to detect just by looking at the code, I would think).

This is not the case. I've written a Lambda which quite purposefully writes to a different path in the source bucket.

I have a Lambda for processing large files; the first phase is a single Lambda splitting the file into chunks which can be processed within the 60 second limit, and then the second phase is a bunch of the same Lambdas processing those chunks.

(Disclosure: I work with nicksergeant at Localytics.)

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