Added

• Added WithOSDescription resource configuration option to set OS (Operating System) description resource attribute (os.description). (#1840)
• Added WithOS resource configuration option to set all OS (Operating System) resource attributes at once. (#1840)
• Added the WithRetry option to the go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp package. This option is a replacement for the removed WithMaxAttempts and WithBackoff options. (#2095)
• Added API LinkFromContext to return Link which encapsulates SpanContext from provided context and also encapsulates attributes. (#2115)
• Added a new Link type under the SDK otel/sdk/trace package that counts the number of attributes that were dropped for surpassing the AttributePerLinkCountLimit configured in the Span's SpanLimits. This new type replaces the equal-named API Link type found in the otel/trace package for most usages within the SDK. For example, instances of this type are now returned by the Links() function of ReadOnlySpans provided in places like the OnEnd function of SpanProcessor implementations. (#2118)

Changed

• The SpanModels function is now exported from the go.opentelemetry.io/otel/exporters/zipkin package to convert OpenTelemetry spans into Zipkin model spans. (#2027)
• Rename the "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc".RetrySettings to RetryConfig. (#2095)
• Rename the "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp".RetrySettings to RetryConfig. (#2095)

Deprecated

• The TextMapCarrier and TextMapPropagator from the go.opentelemetry.io/otel/oteltest package and their associated creation functions (TextMapCarrier, NewTextMapPropagator) are deprecated. (#2114)
• The Harness type from the go.opentelemetry.io/otel/oteltest package and its associated creation function, NewHarness are deprecated and will be removed in the next release. (#2123)
• The TraceStateFromKeyValues function from the go.opentelemetry.io/otel/oteltest package is deprecated. Use the trace.ParseTraceState function instead. (#2122)

Removed

• Removed the deprecated package go.opentelemetry.io/otel/exporters/trace/jaeger. (#2020)
• Removed the deprecated package go.opentelemetry.io/otel/exporters/trace/zipkin. (#2020)
• Removed the "go.opentelemetry.io/otel/sdk/resource".WithBuiltinDetectors function. The explicit With* options for every built-in detector should be used instead. (#2026 #2097)
• Removed the WithMaxAttempts and WithBackoff options from the go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp package. The retry logic of the package has been updated to match the otlptracegrpc package and accordingly a WithRetry option is added that should be used instead. (#2095)
• Removed DroppedAttributeCount field from otel/trace.Link struct. (#2118)

Fixed

• When using WithNewRoot, don't use the parent context for making sampling decisions. (#2032)
• oteltest.Tracer now creates a valid SpanContext when using WithNewRoot. (#2073)
• OS type detector now sets the correct dragonflybsd value for DragonFly BSD. (#2092)
• The OTel span status is correctly transformed into the OTLP status in the go.opentelemetry.io/otel/exporters/otlp/otlptrace package. This fix will by default set the status to Unset if it is not explicitly set to Ok or Error. (#2099 #2102)
• The Inject method for the "go.opentelemetry.io/otel/propagation".TraceContext type no longer injects empty tracestate values. (#2108)