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discord9
b20e22b426
SeriesFrame is the internal transport of the Narthex native PromQL path, and
it could only carry raw samples: an evaluated result had to fall back to a
plain row table. This makes one self-describing Arrow format carry both, so a
receiver decodes a frame from the frame alone, without the scanner, region, or
planning context its producer had.
What is unified is the physical representation and its codec, not the runtime
data structures. RawSeriesChunk, Series, and EvaluatedChunk stay as they are;
only the adapter boundaries branch on the sample shape.
Three combinations are legal and every other one is refused in both
directions:
raw + key + timestamps a storage raw-series scan
raw + explicit + timestamps a raw input whose labels are decoded
evaluated + explicit + grid_spans a compute node's output
An evaluated frame cannot claim a storage key, because the computation may
rewrite its labels; raw samples have no grid to be addressed on. The schema
builder and the declaration parser both enforce that, so a frame cannot be
written or read in a shape no producer could mean.
An evaluated frame declares its GridSpec once in schema metadata and carries
absolute grid positions per row as spans, so a sparse grid costs its runs and
not its holes: nothing is expanded, and no position a chunk does not hold is
filled in. A chunk with no position is legal exactly when it closes its chain,
and it is kept as one frame row, because dropping it would drop the finality
it exists to carry.
Layout is v2 and the writer and reader of the reserved greptime.series.*
metadata live in one place each, so a producer and a consumer cannot spell one
frame two ways. The unreleased v1 format is not read: the in-tree producers,
consumers, tests, and the two frozen wire fixtures all move to v2 together.
Signed-off-by: discord9 <discord9@users.noreply.github.com>
Signed-off-by: discord9 <55937128+discord9@users.noreply.github.com>
(cherry picked from commit 176f6f6479)