Feat: Multi-tiered cache for aws

[conico974]

As discussed in #621.
The new incremental cache work this way :

• First it checks the local in memory LRU cache and that it's not expired ( default TTL is 0 to avoid issue with On Demand revalidation )
• If found but expired, it checks DynamoDB metadata to check if the data has been updated somewhere else ( If it's not been updated it will return the locally retrieved entry )
• Lastly it'll check S3 cache and populate the local LRU cache

It requires both an S3 Bucket and a DynamoDb table
It uses the same env variable as both the default S3 and Tag cache as well as 2 new optional env OPEN_NEXT_LOCAL_CACHE_TTL (default is 0) and OPEN_NEXT_LOCAL_CACHE_SIZE (default is 1000, in nbr of entries)

Warning

This implementation is NOT strongly consistent
If some error happens while writing to DDB, some instance may use outdated local data

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🦋 Changeset detected

Latest commit: 2f06186

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 3 packages

Name	Type
@opennextjs/aws	Minor
app-pages-router	Patch
app-router	Patch

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commit: 2f06186

[vicb]

use Promise.allSetlled() to parallelize?

[conico974]

This is on purpose actually, given how it works we have 3 choice for handling write error failure:

• We could do as it is here, set on S3, then set on DDB, which means that if it fails in DDB, instance that don't have local cache will work as expected. ( But those with local cache will still serve outdated data )
• We could first write in DDB and then S3, which means that in case S3 fail, new instance will fetch outdated data, and existing instance will fetch outdated data.
• Or we could use allSettled but then the behavior will be unpredictable in case one of the 2 fails

I should have added a comment explaining this. One other thing we could do is to let the user chose the behavior they'd want.

I'll update and merge the PR tomorrow in case we should chose another option

[vicb]

Oh you're right 👍
Thanks for explaining very clearly

[vicb]

LGTM, a few nits