Use atomic write for state file to prevent corruption on crash#195
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AnyCPU wants to merge 1 commit intobasecamp:mainfrom
Open
Use atomic write for state file to prevent corruption on crash#195AnyCPU wants to merge 1 commit intobasecamp:mainfrom
AnyCPU wants to merge 1 commit intobasecamp:mainfrom
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saveStateSnapshot() uses os.Create which truncates the state file to zero bytes before writing. If the process is killed (OOM, SIGKILL, power loss) between truncate and write completion, the state file is left empty or with partial JSON.
On restart, RestoreLastSavedState fails to decode the corrupted file and kamal-proxy starts with zero services — dropping all routing for every service behind the proxy.
Fix
Write to a temp file in the same directory, fsync, then atomically rename over the state file. This also fixes a missing f.Close() on the state file handle.