v1.8.0 (2021-11-12)

Context

Add a section for OTel specific values in TraceState.
(#1852)
Add none as a possible value for OTEL_PROPAGATORS to disable context propagation.
(#2052)

Add optional min / max fields to histogram data model.
(#1915,
#1983)
Add exponential histogram to the metrics data model.
(#1935)
Add clarifications on how to handle numerical limits.
(#2007)
Add environment variables for Periodic exporting MetricReader.
(#2038)
Specify that the SDK must support exporters to access meter information.
(#2040)
Add clarifications on how to determine aggregation temporality.
(#2013,
#2032)
Mark Metrics API spec as Stable.
(#2104)
Clarify, fix and expand documentation sections:
(#1966),
(#1981),
(#1995),
(#2002),
(#2010)

Add k8s.container.restart_count Resource attribute.
(#1945)
Add "IBM z/Architecture" (s390x) to host.arch
(#2055)
BREAKING: Remove db.cassandra.keyspace and db.hbase.namespace, and clarify db.name
(#1973)
Add AWS App Runner as a cloud platform
(#2004)
Add Tencent Cloud as a cloud provider.
(#2006)
Don't set Span.Status for 4xx http status codes for SERVER spans.
(#1998)
Add attributes for Apache RocketMQ.
(#1904)
Define http tracing attributes provided at span creation time
(#1916)
Change meaning and discourage use of faas.trigger for FaaS clients (outgoing).
(#1921)
Clarify difference between container.name and k8s.container.name
(#1980)

Clarify default for OTLP endpoint should, not must, be https
(#1997)
Specify the behavior of the OTLP endpoint variables for OTLP/HTTP more strictly
(#1975,
#1985)
Make OTLP/HTTP the recommended default transport (#1969)