Merge metric SDK development branch "new_sdk/main" into "main"

.github/dependabot.yml

@@ -29,7 +29,7 @@ updates:
       interval: weekly
       day: sunday
   - package-ecosystem: gomod
-    directory: /bridge/opencensus/test
+    directory: /bridge/opencensus/opencensusmetric
     labels:
       - dependencies
       - go
@@ -38,7 +38,7 @@ updates:
       interval: weekly
       day: sunday
   - package-ecosystem: gomod
-    directory: /bridge/opentracing
+    directory: /bridge/opencensus/test
     labels:
       - dependencies
       - go
@@ -47,7 +47,7 @@ updates:
       interval: weekly
       day: sunday
   - package-ecosystem: gomod
-    directory: /example/fib
+    directory: /bridge/opentracing
     labels:
       - dependencies
       - go
@@ -56,7 +56,7 @@ updates:
       interval: weekly
       day: sunday
   - package-ecosystem: gomod
-    directory: /example/jaeger
+    directory: /example/fib
     labels:
       - dependencies
       - go
@@ -65,7 +65,7 @@ updates:
       interval: weekly
       day: sunday
   - package-ecosystem: gomod
-    directory: /example/namedtracer
+    directory: /example/jaeger
     labels:
       - dependencies
       - go
@@ -74,7 +74,7 @@ updates:
       interval: weekly
       day: sunday
   - package-ecosystem: gomod
-    directory: /example/opencensus
+    directory: /example/namedtracer
     labels:
       - dependencies
       - go

CHANGELOG.md

@@ -8,6 +8,40 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ## [Unreleased]
 
+### Changed
+
+- The metric SDK in `go.opentelemetry.io/otel/sdk/metric` is completely refactored to comply with the OpenTelemetry specification.
+  Please see the package documentation for how the new SDK is initialized and configured. (#3175)
+
+### Removed
+
+- The metric portion of the OpenCensus bridge (`go.opentelemetry.io/otel/bridge/opencensus`) has been removed.
+  A new bridge compliant with the revised metric SDK will be added back in a future release. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/aggregator/aggregatortest` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/aggregator/histogram` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/aggregator/lastvalue` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/aggregator/sum` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/aggregator` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/controller/basic` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/controller/controllertest` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/controller/time` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/export/aggregation` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/export` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/metrictest` package is removed.
+  A replacement package that supports the new metric SDK will be added back in a future release. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/number` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/processor/basic` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/processor/processortest` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/processor/reducer` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/registry` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/sdkapi` package is removed, see the new metric SDK. (#3175)
+- The `go.opentelemetry.io/otel/sdk/metric/selector/simple` package is removed, see the new metric SDK. (#3175)
+- The `"go.opentelemetry.io/otel/sdk/metric".ErrUninitializedInstrument` variable was removed. (#3175)
+- The `"go.opentelemetry.io/otel/sdk/metric".ErrBadInstrument` variable was removed. (#3175)
+- The `"go.opentelemetry.io/otel/sdk/metric".Accumulator` type was removed, see the `MeterProvider`in the new metric SDK. (#3175)
+- The `"go.opentelemetry.io/otel/sdk/metric".NewAccumulator` function was removed, see `NewMeterProvider`in the new metric SDK. (#3175)
+- The deprecated `"go.opentelemetry.io/otel/sdk/metric".AtomicFieldOffsets` function was removed. (#3175)
+
 ## [1.10.0] - 2022-09-09
 
 ### Added

bridge/opencensus/README.md

@@ -79,50 +79,3 @@ OpenCensus and OpenTelemetry APIs are not entirely compatible.  If the bridge fi
 * Custom OpenCensus Samplers specified during StartSpan are ignored.
 * Links cannot be added to OpenCensus spans.
 * OpenTelemetry Debug or Deferred trace flags are dropped after an OpenCensus span is created.
-
-## Metrics
-
-### The problem: mixing libraries without mixing pipelines
-
-The problem for monitoring is simpler than the problem for tracing, since there
-are no context propagation issues to deal with. However, it still is difficult
-for users to migrate an entire applications' monitoring at once. It
-should be possible to send metrics generated by OpenCensus libraries to an
-OpenTelemetry pipeline so that migrating a metric does not require maintaining
-separate export pipelines for OpenCensus and OpenTelemetry.
-
-### The Exporter "wrapper" solution
-
-The solution we use here is to allow wrapping an OpenTelemetry exporter such
-that it implements the OpenCensus exporter interfaces. This allows a single
-exporter to be used for metrics from *both* OpenCensus and OpenTelemetry.
-
-### User Journey
-
-Starting from an application using entirely OpenCensus APIs:
-
-1. Instantiate OpenTelemetry SDK and Exporters.
-2. Replace OpenCensus exporters with a wrapped OpenTelemetry exporter from step 1.
-3. Migrate libraries individually from OpenCensus to OpenTelemetry
-4. Remove OpenCensus Exporters and configuration.
-
-For example, to swap out the OpenCensus logging exporter for the OpenTelemetry stdout exporter:
-
-```go
-import (
-	"go.opencensus.io/metric/metricexport"
-	"go.opentelemetry.io/otel/bridge/opencensus"
-	"go.opentelemetry.io/otel/exporters/stdout"
-	"go.opentelemetry.io/otel"
-)
-// With OpenCensus, you could have previously configured the logging exporter like this:
-//       import logexporter "go.opencensus.io/examples/exporter"
-//       exporter, _ := logexporter.NewLogExporter(logexporter.Options{})
-// Instead, we can create an equivalent using the OpenTelemetry stdout exporter:
-openTelemetryExporter, _ := stdout.New(stdout.WithPrettyPrint())
-exporter := opencensus.NewMetricExporter(openTelemetryExporter)
-
-// Use the wrapped OpenTelemetry exporter like you normally would with OpenCensus
-intervalReader, _ := metricexport.NewIntervalReader(&metricexport.Reader{}, exporter)
-intervalReader.Start()
-```