An import failure occurs when externally supplied data cannot be read or its resources cannot be created. Treat it differently from export failure: retrying may not help and may create duplicates. section 23.3.7
Handle the main failure modes explicitly:
- Report entries that fail validation in the long-running operation results; retries cannot fix invalid data. section 23.3.7
- Assume a transient failure may have created resources before stopping, so a retry can produce duplicates. section 23.3.7
- Use a transaction when supported and appropriately sized, but recognize that some storage systems lack full transactional semantics or cannot handle enormous transactions. section 23.3.7
Request identifiers for deduplication
Represent imported resources with stable request identifiers, such as `{ importRequestId: "abc", sender: "users/1", content: "hi" }`, so repeated attempts can be distinguished. section 23.3.7
