async-append-only-log | A new append-only-log for SSB purposes

async-append-only-log is a JavaScript library. async-append-only-log has no bugs, it has no vulnerabilities and it has low support. You can install using 'npm i async-append-only-log' or download it from GitHub, npm.

This module is heavily inspired by flumelog-aligned-offset. It is an attempt to implement the same concept but in a simpler fashion, making it easier to reason about the code. A log is the lowest part of the SSB stack, so it should extremly stable while still maintaining good performance. A log consists of a number of blocks, that contain a number of records. A record is simply it's length, as a 16-bit unsigned integer, followed by the data bytes. A record must be in one and only one block, which means there probably will be some empty space at the end of a block. Blocks are always written in full. In contrast to flumelog-aligned-offset there is no additional length after the data in a record and no pointer at the end of a block. These were there to be able to iterate over the log in reverse, but I have never seen the need for that. Writing to the log is always async. Note this is different from flumelog-offset and flumelog-aligned-offset. The since observable will be updated once the data is written. The onDrain callback can be used to know when data has been written if needed. Streaming will only emit values that have been written to storage. This is to ensure that a view will never get ahead of the main log and thus end up in a bad state if the system crashes before data is written. get will return values that have not been written to disk yet. This module is not compatible with flume without a wrapper around stream as it uses the same terminology as JITDB and ssb-db2 of using offset for the byte position of a record instead of seq.