InfluxDB exporter/receiver do not sum/decompose histogram bucket counts

[jacobmarble]

Component(s)

exporter/influxdb, receiver/influxdb

What happened?

Description

The InfluxDB/otel conversion library assumed that OpenTelemetry histogram buckets are cumulative, like Prometheus histogram buckets. The result is that the bucket counts are always incorrect after conversion.

Originally reported here: influxdata/influxdb-observability#60

Steps to Reproduce

Either:

• Configure otelcol-contrib to export InfluxDB/Telegraf metrics with Prometheus v1 or v2 schema
• Receive an OpenTelemetry histogram via OTLP

Or:

• Configure otelcol-contrib to receive InfluxDB/Telegraf metrics with Prometheus v1 or v2 schema
• Receive a histogram from Telegraf via line protocol

Expected Result

This otel histogram:

0.05: 24054
0.1: 9390
0.2: 66948
0.5: 28997
1: 4599
inf: 10332

Yields this line protocol (schema is Telegraf Prometheus v1 in the example):

count=144320,sum=53423,0.05=24054,0.1=33444,0.2=100392,0.5=129389,1=133988

And visa-versa.

Actual Result

This otel histogram:

0.05: 24054
0.1: 9390
0.2: 66948
0.5: 28997
1: 4599
inf: 10332

Yields this line protocol (schema is Telegraf Prometheus v1 in the example):

count=144320,sum=53423,0.05=24054,0.1=9390,0.2=66948,0.5=28997,1=4599

And this line protocol:

count=144320,sum=53423,0.05=24054,0.1=33444,0.2=100392,0.5=129389,1=133988

Yields this otel histogram:

0.05: 24054
0.1: 33444
0.2: 100392
0.5: 129389
1: 133988
inf: 144320

Collector version

v0.73.0

Environment information

Environment

OS: MacOS 13.2 (and surely every OS)
Compiler(if manually compiled): go 1.19.5 (and surely every compiler)

OpenTelemetry Collector configuration

No response

Log output

No response

Additional context

No response