* refactor: improve writer buffer consumer interface
The change looks huge but is actually rather simple. To
understand the interface change, let me first explain what we want:
- be able to fetch watermarks for any sequencer
- have streams:
- each streams tracks a sequencer and has an offset state (no read
multiplexing)
- we can seek a stream
- seeking and streaming cannot be done at the same time (that would be
weird and likely leads to many bugs both in write buffer and in the
user code)
- ideally we don't need to create streams of all sequencers but can
choose a subset
Before this change we had one mutable consumer struct where you can get
all streams and watermark functions (this mutable-borrows the consumer)
or you can seek a single stream (this also mutable-borrows the
consumer). This is a bit weird for multiple reasons:
- you cannot seek a single stream without dropping all of them
- the mutable-borrow construct makes it really difficult to pass the
streams into separate threads
- the consumer is boxed (because its mutable) which makes it more
difficult to handle in a large-scale application
What this change does is the following:
- you have an immutable consumer (similar to the producer)
- the consumer offers the following methods:
- get the set of sequencer IDs
- get watermark for any sequencer
- get a stream handler (see next point) for any sequencer
- the stream handler captures the stream state (offset) and provides you
a standard `Stream<_>` interface as well as a seek function.
Mutable-borrows ensure that you cannot use both at the same time.
The stream handler provides you the stream via `handler.stream()`. It
doesn't implement `Stream<_>` itself because the way boxing, dynamic
dispatch work, and pinning interact (i.e. I couldn't get it to work
without the indirection).
As a bonus point (which we don't use however) you can now create
multiple streams for the same sequencer and they all have their own
offset.
* fix: review comments
Co-authored-by: Carol (Nichols || Goulding) <193874+carols10cents@users.noreply.github.com>
Co-authored-by: Carol (Nichols || Goulding) <193874+carols10cents@users.noreply.github.com>
Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
* feat: Add db_name/namespace to DmlWrite and DmlDelete
This is required for the new ingester to be able to work with the write buffer. The protobuf that gets serialized over Kafka already includes the database name, it just wasn't getting carried through to the marshaled Dml operation.
* fix: database != namespace, propagation through write buffer
Co-authored-by: Marco Neumann <marco@crepererum.net>
Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
* refactor: have the deduplicate work without chunk statistics
* test: more tests for duplicates data on different combinations of record batches
* refactor: address review comments
This will be helpful when we want to batch DML operations in memory
(e.g. when using RSKafka).
This also ensures that `MBChunk` accounts for the column names that
are stored within `MutableBatch`.
* refactor: Extract JobRegistry from the server crate
Both the server crate and a db crate that I'm about to extract depend on
JobRegistry, so to avoid making circular dependencies, extract the
JobRegistry to its own crate.
* refactor: Move db out of server into its own crate
Fixes#2821.