fix: suppress proxy blocking during grace period after network change - #184
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fix: suppress proxy blocking during grace period after network change#184derbauer97 wants to merge 1 commit into
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After a network change is detected (addrsChanged returns true), checkForUpdates resets the blocklist. However, concurrent requests that fail because the network is not yet fully stable can immediately re-block the proxy, causing alpaca to stay in DIRECT mode for up to 5 minutes. Add a configurable grace period after network changes during which blockProxy() calls are suppressed. This gives the network time to stabilize before alpaca starts evaluating proxy reachability. Configurable via ALPACA_GRACE_PERIOD env var (seconds). Default: 0 (disabled). Set to e.g. 3 to enable. Fixes: samuong#183 Signed-off-by: FlorianFlBauer <florian.fl.bauer@deutschebahn.com>
derbauer97
requested review from
camh-,
juliaogris,
marcelocantos and
samuong
as code owners
July 16, 2026 11:29
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Problem
After switching from a network where the corporate proxy is unreachable (e.g. mobile hotspot) back to the corporate network, alpaca can get stuck in DIRECT mode for up to 5 minutes despite the proxy being reachable again.
Root Cause
When
checkForUpdates()detects a network change and resets the blocklist, concurrent requests that fail (because the network is not yet fully stable) immediately re-block the proxy viablockProxy(). SinceaddrsChanged()no longer returns true (addresses haven't changed since the reset), the blocklist is never cleared again until the 5-minute TTL expires.Fix
Add a configurable grace period after network changes during which
blockProxy()calls are suppressed. This gives the network time to stabilize before alpaca evaluates proxy reachability.ALPACA_GRACE_PERIOD(seconds)0(disabled, preserves existing behavior)3to enableTesting
TestBlockProxySuppressedDuringGracePeriodFixes #183