feat: add CSV votes cleanup strategy

[wa0x6e]

Votes CSV reports will grow in count and size over time, and will increase the AWS storage cost.

We should have a prune strategy, which remove old and files that were not accessed for some time. In case someone request them again, they can trigger the cache creation and download them again.

A very basic strategy:

• Get all files older than 6 months.
• If the file was not accessed within the last 3 months, remove it from cache, freeing space

[ChaituVR]

I think it is ok to keep this cache 🙈 @bonustrack what do you think? would it be costly?

[ChaituVR]

I didn't try before, but maybe something like the expiry date will help this case (if we need this)

https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/S3.html#putBucketLifecycle-property

[wa0x6e]

I think there is no api currently returning the bucket size. Only way is to consult the admin panel.

We do not have analytics, but I believe that old proposals are forgotten forever, there is no need to keep it’s cache. In the worst case, user can trigger the cache again.

Setting expiry is a possibility, will look into it

[ChaituVR]

If expiry doesn't work, another idea is to have subdirectories with auto incremental numbers for every six months

[wa0x6e]

I didn't try before, but maybe something like the expiry date will help this case (if we need this)

https://docs.aws.amazon.com/AWSJavaScriptSDK/latest/AWS/S3.html#putBucketLifecycle-property

This one is expiring the whole bucket, there seems to be no way to expire files individually.

Subdirectory method works only if we expire by creation time, but this is not the case, we expire also by last access date, in addition of creation time.

[ChaituVR]

Yea we can just delete files once in a while if it is adding lot of cost,