core: Add truncation to message log #526
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kulakowski
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If there's no rush I'd like to finish the review after #496 lands
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| let to_retain = self.open_segment_max_offset - offset; | ||
| let mut retained = 0; | ||
| for message in iter.by_ref().take(to_retain as usize) { | ||
| let _ = message?; |
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This is the only place I don't immediately understand, just because I don't know what would cause this to return via the ?. Could you comment about that please?
Adds a method `reset_to(offset)` to `MessageLog`, which allows to truncate the log to the given message offset. Note that this currently requires to iterate over the last segment until the message offset is found -- we may in the future maintain an offset index (a la Kafka) to be able to seek closer to the desired message offset. `reset_to` subsumes the unused `reset_hard` method, and is itself not yet used (this will be added in a later patch).
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Description of Changes
Adds a method
reset_to(offset)toMessageLog, which allows to truncate the log to the given message offset.Note that this currently requires to iterate over the last segment until the message offset is found -- we may in the future maintain an offset index (a la Kafka) to be able to seek closer to the desired message offset.
reset_tosubsumes the unusedreset_hardmethod, and is itself not yet used (this will be added in a later patch).Note The first commit is submitted separately in #496
API and ABI
If the API is breaking, please state below what will break
Expected complexity level and risk
3