prometheus/tsdb/tsdbblockutil.go
Dieter Plaetinck cda025b5b5
TSDB: demistify SeriesRefs and ChunkRefs (#9536)
* TSDB: demistify seriesRefs and ChunkRefs

The TSDB package contains many types of series and chunk references,
all shrouded in uint types.  Often the same uint value may
actually mean one of different types, in non-obvious ways.

This PR aims to clarify the code and help navigating to relevant docs,
usage, etc much quicker.

Concretely:

* Use appropriately named types and document their semantics and
  relations.
* Make multiplexing and demuxing of types explicit
  (on the boundaries between concrete implementations and generic
  interfaces).
* Casting between different types should be free.  None of the changes
  should have any impact on how the code runs.

TODO: Implement BlockSeriesRef where appropriate (for a future PR)

Signed-off-by: Dieter Plaetinck <dieter@grafana.com>

* feedback

Signed-off-by: Dieter Plaetinck <dieter@grafana.com>

* agent: demistify seriesRefs and ChunkRefs

Signed-off-by: Dieter Plaetinck <dieter@grafana.com>
2021-11-06 15:40:04 +05:30

77 lines
1.8 KiB
Go

// Copyright 2019 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package tsdb
import (
"context"
"fmt"
"path/filepath"
"github.com/go-kit/log"
"github.com/prometheus/prometheus/storage"
)
var ErrInvalidTimes = fmt.Errorf("max time is lesser than min time")
// CreateBlock creates a chunkrange block from the samples passed to it, and writes it to disk.
func CreateBlock(series []storage.Series, dir string, chunkRange int64, logger log.Logger) (string, error) {
if chunkRange == 0 {
chunkRange = DefaultBlockDuration
}
if chunkRange < 0 {
return "", ErrInvalidTimes
}
w, err := NewBlockWriter(logger, dir, chunkRange)
if err != nil {
return "", err
}
defer func() {
if err := w.Close(); err != nil {
logger.Log("err closing blockwriter", err.Error())
}
}()
ctx := context.Background()
app := w.Appender(ctx)
for _, s := range series {
ref := storage.SeriesRef(0)
it := s.Iterator()
lset := s.Labels()
for it.Next() {
t, v := it.At()
ref, err = app.Append(ref, lset, t, v)
if err != nil {
return "", err
}
}
if it.Err() != nil {
return "", it.Err()
}
}
if err = app.Commit(); err != nil {
return "", err
}
ulid, err := w.Flush(ctx)
if err != nil {
return "", err
}
return filepath.Join(dir, ulid.String()), nil
}