v1.2.0 release

Release of core packages:

• opentelemetry-api
• opentelemetry-sdk

and exporter packages:

• opentelemetry-exporter-otlp ( gRPC + HTTP/JSON )
• opentelemetry-exporter-etw
• opentelemetry-exporter-zipkin
• opentelemetry-exporter-jaeger ( thrift + UDP/HTTP )

Changelog

API

• Allow to use external abseil for bazel targets (#1172)

Exporters

• InMemorySpanExporter shutdown fix (#1161)
• Fix leak in Jaeger exporter (#1160)
• Importing gsl::span if std::span is not available (#1167)
• Synchronized calls to Exporter::Export & Shutdown (#1164)
• OTLP http exporter block thread (#1163)

Experimental features

• Logger: propagating resources through LoggerProvider (#1154)
• Logger: support for instrumentation library (#1149)
• Add log level for internal log of sdk (#1147)
• Metrics SDK: View API (#1110)

Notes on experimental features:

#1149 and #1154 from above list introduced API changes which are not backward compatible with previous logs, please update API package to this release if ENABLE_LOGS_PREVIEW is turned on (it is turned off by default).