Replace the commit-pinned golangci-lint install refs in Dockerfile and
script/bootstrap with the v2.12.2 version pin, and replace .golangci.yml
with the canonical v2-schema config (lint settings now live under
linters.settings, so the lll/funlen/cyclop/dupl thresholds are actually
applied).
Fix all findings surfaced by the newly-applied config:
- goconst: introduce shared constants for repeated status, priority,
and DNS fixture strings in watcher.go and the notify, state, and
watcher tests
- dupl: consolidate duplicated ntfy/slack HTTP-error tests and
SendNotification endpoint-error tests behind shared helpers
- lll: wrap long test table entries and comments; shorten one inline
nolint justification
## Summary
Notifications were fire-and-forget: if Slack, Mattermost, or ntfy was temporarily down, changes were silently lost. This adds automatic retry with exponential backoff and jitter to all notification endpoints.
## Changes
### New file: `internal/notify/retry.go`
- `RetryConfig` struct with configurable max retries, base delay, max delay
- `backoff()` computes delay as `BaseDelay * 2^attempt`, capped at `MaxDelay`, with ±25% jitter
- `deliverWithRetry()` wraps any send function with the retry loop
- Defaults: 3 retries (4 total attempts), 1s base delay, 10s max delay
- Context-aware: respects cancellation during retry sleep
- Injectable `sleepFn` for test determinism
### Modified: `internal/notify/notify.go`
- Added `retryConfig` and `sleepFn` fields to `Service`
- Updated `dispatchNtfy`, `dispatchSlack`, `dispatchMattermost` to wrap sends in `deliverWithRetry`
- Structured logging: warns on each retry, logs error only after all retries exhausted, logs info on success after retry
### Modified: `internal/notify/export_test.go`
- Added test helpers: `SetRetryConfig`, `SetSleepFunc`, `DeliverWithRetry`, `BackoffDuration`
### New file: `internal/notify/retry_test.go`
- Backoff calculation tests (exponential increase, max cap with jitter)
- `deliverWithRetry` unit tests: first-attempt success, transient failure recovery, exhausted retries, context cancellation
- Integration tests via `SendNotification`: transient failure retries, all-endpoints retry independently, permanent failure exhausts retries
## Verification
- `make fmt` ✅
- `make check` (format + lint + tests + build) ✅
- `docker build .` ✅
- All existing tests continue to pass unchanged
- No DNS client mocking — notification tests use `httptest` servers
closes #62
Co-authored-by: clawbot <clawbot@noreply.git.eeqj.de>
Reviewed-on: #87
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>
