Flakiness in e2e tests in CI #2687
Description
Why
We have noticed a lot of flakiness recently on the end to end tests in the CI:
- https://github.com/input-output-hk/mithril/actions/runs/17555311799/job/49859894491#step:6:1356
- https://github.com/input-output-hk/mithril/actions/runs/17557153779/job/49865340567#step:6:1632
- https://github.com/input-output-hk/mithril/actions/runs/17557672400/job/49867031241#step:6:1765
What
Investigate and fix the source of flakiness.
How
- Investigate the source of flakiness
- Fix the source of flakiness
Analysis
After investigation, it appears that the client CLI is using a temporary folder during the verification of the Cardano database (during the downloaded digests verification) which is created and deleted. The problem occurs when multiple client are run in parallel: some process may not find the folder which has been deleted by another process.