diff options
Diffstat (limited to 'vendor/go.opencensus.io/stats/view/collector.go')
-rw-r--r-- | vendor/go.opencensus.io/stats/view/collector.go | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/vendor/go.opencensus.io/stats/view/collector.go b/vendor/go.opencensus.io/stats/view/collector.go new file mode 100644 index 000000000..32415d485 --- /dev/null +++ b/vendor/go.opencensus.io/stats/view/collector.go @@ -0,0 +1,87 @@ +// Copyright 2017, OpenCensus 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 view + +import ( + "sort" + + "go.opencensus.io/exemplar" + + "go.opencensus.io/internal/tagencoding" + "go.opencensus.io/tag" +) + +type collector struct { + // signatures holds the aggregations values for each unique tag signature + // (values for all keys) to its aggregator. + signatures map[string]AggregationData + // Aggregation is the description of the aggregation to perform for this + // view. + a *Aggregation +} + +func (c *collector) addSample(s string, e *exemplar.Exemplar) { + aggregator, ok := c.signatures[s] + if !ok { + aggregator = c.a.newData() + c.signatures[s] = aggregator + } + aggregator.addSample(e) +} + +// collectRows returns a snapshot of the collected Row values. +func (c *collector) collectedRows(keys []tag.Key) []*Row { + rows := make([]*Row, 0, len(c.signatures)) + for sig, aggregator := range c.signatures { + tags := decodeTags([]byte(sig), keys) + row := &Row{Tags: tags, Data: aggregator.clone()} + rows = append(rows, row) + } + return rows +} + +func (c *collector) clearRows() { + c.signatures = make(map[string]AggregationData) +} + +// encodeWithKeys encodes the map by using values +// only associated with the keys provided. +func encodeWithKeys(m *tag.Map, keys []tag.Key) []byte { + vb := &tagencoding.Values{ + Buffer: make([]byte, len(keys)), + } + for _, k := range keys { + v, _ := m.Value(k) + vb.WriteValue([]byte(v)) + } + return vb.Bytes() +} + +// decodeTags decodes tags from the buffer and +// orders them by the keys. +func decodeTags(buf []byte, keys []tag.Key) []tag.Tag { + vb := &tagencoding.Values{Buffer: buf} + var tags []tag.Tag + for _, k := range keys { + v := vb.ReadValue() + if v != nil { + tags = append(tags, tag.Tag{Key: k, Value: string(v)}) + } + } + vb.ReadIndex = 0 + sort.Slice(tags, func(i, j int) bool { return tags[i].Key.Name() < tags[j].Key.Name() }) + return tags +} |