* Split the database trait into read and transactions.
The transaction traits will encapsulate all database changes and also expect
READ-and-lock operations to read and lock records from the database for
exclusive access, thereby avoiding race conditions.
The Transaction trait expects a `rollback` operation on Drop unless the
transaction has been committed.
* fix: melt quote duplicate error
This change stops a second melt quote from being created
if there is an existing valid melt quote for an invoice already.
If the first melt quote has expired then we allow for a new melt quote to be created.
---------
Co-authored-by: thesimplekid <tsk@thesimplekid.com>
* Fix SQLite race condition
Bug: https://github.com/crodas/cdk/actions/runs/15732950296/job/44339804072#step:5:1853
Reason: When melting in parallel, many update the melt status and attempt to
add proofs and they fail when adding the proof and the rollback code kicks in.
The loser process removes all the proofs, and the winner process has no proof
later on.
Fix: Modify `update_melt_quote_state` requirements and implementation to allow
only one winner.
This will be solved by design with a transaction writer trait
* Remove `melt_request`
Fixes#809
* Remove `get_melt_request` from db trait
Bug: https://github.com/crodas/cdk/actions/runs/15732950296/job/44339804072#step:5:1853
Reason: When melting in parallel, many update the melt status and attempt to
add proofs and they fail when adding the proof and the rollback code kicks in.
The loser process removes all the proofs, and the winner process has no proof
later on.
Fix: Modify `update_melt_quote_state` requirements and implementation to allow
only one winner.
This will be solved by design with a transaction writer trait
Bug: https://github.com/cashubtc/cdk/actions/runs/15683152414/job/44190084378?pr=822#step:5:19212
Reason: a race condition between removing proofs while melting and the quote states being updated.
Solution:
1. Error on duplicate proofs
2. Read quote when updating to avoid race conditions and rollbacks
Real solution: A transaction trait in the storage layer. That is coming next
