- introduce Query Context (Qcx) for managing database-per-shard.
- replaces the MultiTx, so mtx.go is retired and removed.
- introduces the HolderConfig struct and all Holders now have
a path from birth.
- rbf speedups on bitwise writes
- badgerdb is removed due to unresolvable write conflicts.
fixes#703#676
The testhook/ package provides an easy way to set up multiple
hooks to run before/after tests are run.
The audit hooks track open and closes of storage backends,
files, indexes, and holders, for example. A tempdir wrapper
creates temporary directories which are automatically cleaned up
when the test ends. Any kind of resource creation that
should be closed at test conclusion can be tracked. We
will complain at the end of the TestMain if resources are
leaking.
Leaks under go1.13:
We use a wrapper function which is a no-op for go 1.13, but actually
calls testing.TB.Cleanup in go1.14, so we can still build with 1.13 even though
tests will leak files all over the place there. Because of this,
don't run the testhook tests when using 1.13, as they'll always fail.
- the test/pilosa.go http client now times out after 10 seconds
to help diagnose hung server situations.
- Makefile targets added to get better progress reports.
- Atomic record contains multiple ImportRequest and
ImportValueRequest, plus ability to Clear individual requests.
- adds http handlers for importing AtomicRecord.
- rbf had races around the new rootRecords cache in tx
- rbf tx needed a write lock on the db now that rootRecords are written
- added a global registry for rbfDB to correctly dedup instances
- implement DeleteFragment, DeleteIndex for rbf
- use badger style keys for rbf to allow content checksumming to be list
containers in the same order
- lots of other integration of rbf into pilosa layer.
This is sort of large, but it's annoyingly difficult to
separate out.
The basic idea is to allow us to have a single holder-iterating
block of code, which is associated with the holder, that can be used
for various things, like the snapshot queue background scan, or
for inspect operations.
We invent the concept of a HolderFilter, which is a thing that
can decide what things in a holder it cares about, and a HolderOperator,
which can also process those things selectively.
In the process, we fix up a couple of subtle bugs in the
inspect logic; specifically, the assumption that the mapped flag could
tell you whether a container was modified by the ops log doesn't
work with mmap, so we have a shiny new flag which is used to track
that, internal to the roaring/container code.
All of this leads to the actual *point* of this exercise, which is
making it easier to create an /inspect endpoint which produces almost
the same data we'd have gotten from `pilosa inspect` on a data directory;
the distinction is that it doesn't try to identify the distinction
between data from disk and data from operations since the file was
loaded. Possibly it should, but it doesn't yet.
The snapshot queue is now implemented using the HolderOperator
design, which requires some subtle changes to how it works, but
overall makes it easier to follow the snapshot queue logic,
and also shares that logic with the way Inspect works.
The holder's snapshot queue is now provided by the server, in
a default environment.
The queueless snapshot queue no longer triggers snapshots on
enqueue -- it turns out that breaks badly, because a key
point about enqueueing a snapshot is that it's safe to do it
*during* a transaction on that fragment, and triggering a
snapshot during a transaction actually causes horrible errors
as the ops log ends up being the old file, which we close.
Related to this, we also need to prevent closed fragments from
trying to snapshot, so we track fragment openness when opening
or closing, and bail on trying to snapshot a fragment which is closed.
We also stop using the queueless snapshot queue during tests,
because that's a horrible idea.
We copy a little bit of the partition logic from the cluster code so
we don't have to expose it all, this lets us check whether the node
we're looking at is the one which should be primary for a given shard,
and if not, identify which node would be. This works only when
pointed at a data directory, for now.
The test cases for the holder have to be internal, because pilosa
doesn't export view/fragment, just Index/Field. This means that the
holder test cases can't just use the test/* package, so they duplicate
some of its logic, approximately.
We want to be able to control whether or not we use roaring to
serialize Rows, which means serializers have to be able to be
distinct.
We also make corresponding changes to http/handler.go to have
it use the exported serializers directly rather than the API's
serializer (which is always the base protobuf serializer
right now, and if it weren't, that would be bad because we
were assuming it was).
When we're accepting protobuf from a pilosa server, flag that
we'll accept roaring bitmaps as opposed to the naive column
representation.
I think this will improve the transaction response messages Kuba
mentioned where it was an empty transaction instead of a nil or not
there... if not it should make it easier to do that anyhow.
