early-exit optimization using a HEAD request to check for existence f…

[stone-monkeys]

Missing Early-Exit Optimization

CircleCI’s native save_cache checks if the key already exists before recompressing. The S3 orb always creates the archive even if it already exists in the bucket. That’s wasted time.

Would be great to implement:

HEAD request to check existence before compressing

If exists > skip compression/upload

HEAD Request Check:

• Before compressing anything, the script now performs a aws s3api head-object call to check if the cache already exists in S3

Early Exit: If the object exists, it prints a message and exits with success (0), skipping:

• The expensive tar compression step
• S3 configuration
• The upload operation

Proceed if Missing:

• Only if the cache doesn't exist will it proceed with compression and upload