Currently, we check the cache only immediately before attempting to send
an email address. However, we only reach that point if the rate limiter
(used to respect the daily API quota) permits it. As a result, around
40% of sends are wasted on email addresses that are ultimately skipped
due to cache hits.
Replace the pre-send cache `Seen` check with an atomic `StoreIfAbsent`
executed before the `limiter.Wait()` so that limiter tokens are consumed
only for email addresses that actually need sending. Skip the
`limiter.Wait()` on cache hits, remove cache entries only when a send
fails, and increment metrics only on successful sends.
Add a new boulder service, email-exporter, which uses the Pardot API
client added in #8016 and the email.Exporter gRPC service added in
#8017.
Add pardot-test-srv, a test-only service for mocking communication with
Salesforce OAuth and Pardot APIs in non-production environments. Since
Salesforce does not provide Pardot functionality in developer sandboxes,
pardot-test-srv must run in all non-production environments (e.g.,
sre-development and staging).
Integrate the email-exporter service with the WFE and modify
WFE.NewAccount and WFE.UpdateAccount to submit valid email contacts.
Ensure integration tests verify that contacts eventually reach
pardot-test-srv.
Update configuration where necessary to:
- Build pardot-test-srv as a standalone binary.
- Bring up pardot-test-srv and cmd/email-exporter for integration
testing.
- Integrate WFE with cmd/email-exporter when running test/config-next.
Closes#7966
Samantha Frank