fix: flush accumulated buffer on EOF without trailing newline#976
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Vitalymt wants to merge 3 commits into
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fix: flush accumulated buffer on EOF without trailing newline#976Vitalymt wants to merge 3 commits into
Vitalymt wants to merge 3 commits into
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When a file doesn't end with a newline character, the last line is silently dropped. The read loop accumulates data in accumBuf until it finds a '\n', but at EOF the remaining data is saved to job.tail without ever being emitted through controller.In(). If the file is never written to again, that data is lost permanently. Fix: emit accumBuf as a final event before calling processEOF when EOF is reached and the buffer is non-empty. Clear both accumBuf and job.tail afterward to prevent re-emission on file truncation. Fixes ozontech#912
DmitryRomanov
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DmitryRomanov
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Please look at the failed tests:
https://github.com/ozontech/file.d/actions/runs/26528924982?pr=976#user-content-tr-BjxUNA-r0s42
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| // Flush remaining data when EOF is reached and there's no trailing newline. | ||
| // Without this, the last line of a file that doesn't end with '\n' is silently dropped. | ||
| if isEOFReached && len(accumBuf) > 0 { |
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isEOFReached is checked twice.
It looks cleaner:
if isEOFReached {
// Flush remaining data when EOF is reached and there's no trailing newline.
if len(accumBuf) > 0 {
// ...
}
err := w.processEOF(...)
}
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Good catch, done. Nested the flush inside the single isEOFReached block.
Nest the accumBuf flush inside the existing isEOFReached check instead of testing the flag twice. Functionally identical, just cleaner structure.
- Remove should_ok_and_empty_when_read_not_ready_line (duplicates should_emit_last_line_without_trailing_newline) - Update no_new_line test: expect data to be emitted at EOF even without trailing newline
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Problem
When a file doesn't end with a newline character, the last line is silently dropped.
The read loop in
worker.goaccumulates data inaccumBufuntil it finds a\n. At EOF, the remaining data is saved tojob.tailwithout ever being emitted throughcontroller.In(). If the file is never written to again, that data is lost permanently.Steps to reproduce:
\n:echo -n "hello" > /tmp/test.txtFix
Emit
accumBufas a final event before callingprocessEOFwhen EOF is reached and the buffer is non-empty. Clear bothaccumBufandjob.tailafterward to prevent re-emission on file truncation.Changes:
plugin/input/file/worker.go: +8 lines — flush buffer on EOFplugin/input/file/worker_test.go: updated existing test expectation + added multi-line test caseFixes #912