Is there a way to import the extra info of outgoing transactions to a restored wallet?

Question

Let's say I have a wallet with some outgoing transactions. The transaction history shows the recipients' addresses, the payment ids, etc.

Now let's suppose that the wallet file gets corrupted for some reason. I then create a new wallet file using the mnemonic seed of the corrupted wallet, rescan the blockchain, and I get a restored wallet.

However, the transaction history of the restored wallet doesn't show the recipients' addresses of outgoing transactions because they are neither stored in the blockchain nor computable from blockchain data, but only kept locally in the wallet cache.

Is there a way to export the extra info of outgoing transactions (recipient address, payment id, transaction key) of a wallet to a file, and import that file to a restored wallet in order to get back the fully detailed transaction history?

Answer 1

I think you know the answer to that one, since you say "because they are neither stored in the blockchain nor computable from blockchain data, but only kept locally in the wallet cache".

The answer is: make backups.

Backups can be stored on inexpensive write once media, and both encrypted and signed.

Of course, make sure your only copy of the keys isn't on the backed up data :)

As for an external export/import of this, there is none. This would need to be encrypted also, since it's private data. And if the cache gets corrupted or erased, then why not the exported file ? True, it's a brittle format, due to different boost versions used in binaries, but this will be solved in the near/medium future (and there are workarounds, see https://github.com/monero-project/monero/issues/1106).