DOCS-4321 Add Go instructions for OTel inst (DataDog#17897)

* add go * add note about dependence on OTel * nit

Author: kayayarai

config/_default/menus/menus.en.yaml

@@ -1442,6 +1442,11 @@ main:
  parent: tracing_otel_inst
  identifier: tracing_otel_inst_ruby
  weight: 103
+ - name: Go
+ url: tracing/trace_collection/otel_instrumentation/go/
+ parent: tracing_otel_inst
+ identifier: tracing_otel_inst_go
+ weight: 104
  - name: .NET
  url: tracing/trace_collection/otel_instrumentation/dotnet/
  parent: tracing_otel_inst

content/en/tracing/trace_collection/otel_instrumentation/go.md

@@ -0,0 +1,81 @@
+---
+title: Custom Instrumentation of Go Applications with the OpenTelemetry API
+kind: documentation
+description: 'Instrument your Go application with OTel API to send traces to Datadog'
+code_lang: go
+type: multi-code-lang
+code_lang_weight: 30
+further_reading:
+ - link: 'tracing/glossary/'
+ tag: 'Documentation'
+ text: 'Explore your services, resources, and traces'
+---
+
+{{% otel-custom-instrumentation %}}
+
+## Requirements and limitations
+
+- Datadog Go tracing library `dd-trace-go` version 1.5.0 or greater.
+- Go version 1.8 or greater.
+- The Datadog OTel API implementation is dependent on upstream [OpenTelemetry Go][6].
+
+The following OTel features are implemented in the Datadog library as noted:
+
+| Feature | Support notes |
+|---------------------------------------|------------------------------------|
+| [OTel Context propagation][1] | [Datadog distributed header format][9] is used instead. |
+| [Span processors][2] | Unsupported |
+| [Span Exporters][3] | Unsupported |
+| Trace/span [ID generators][4] | ID generation is performed by `ddtrace`. |
+
+
+## Configuring OTel to use the Datadog trace provider
+
+1. Add your desired manual OTel instrumentation to your Go code following the [OTel Go Manual Instrumentation documentation][5].
+
+2. Install the OpenTelemetry package `go.opentelemetry.io/otel` using the command:
+
+ ```shell
+ go get go.opentelemetry.io/otel
+ ```
+
+3. Install the Datadog OpenTelemetry wrapper package `gopkg.in/DataDog/dd-trace-go.v1/ddtrace/opentelemetry` using the command:
+
+ ```shell
+ go get gopkg.in/DataDog/dd-trace-go.v1/ddtrace/opentelemetry
+ ```
+
+4. Import packages in the code:
+
+ ```go
+ import (
+ "go.opentelemetry.io/otel"
+ ddotel "gopkg.in/DataDog/dd-trace-go.v1/ddtrace/opentelemetry"
+ )
+ ```
+
+5. Create a TracerProvider, optionally providing a set of options, that are specific to Datadog APM, and defer the Shutdown method, which stops the tracer:
+
+ ```go
+ provider := ddotel.NewTracerProvider()
+ defer provider.Shutdown()
+ ```
+
+6. Use the Tracer Provider instance with the OpenTelemetry API to set the global TracerProvider:
+
+ ```go
+ otel.SetTracerProvider(provider)
+ ```
+ 
+7. Run your application.
+
+Datadog combines these OpenTelemetry spans with other Datadog APM spans into a single trace of your application.
+
+
+[1]: https://opentelemetry.io/docs/instrumentation/go/manual/#propagators-and-context
+[2]: https://opentelemetry.io/docs/reference/specification/trace/sdk/#span-processor
+[3]: https://opentelemetry.io/docs/reference/specification/trace/sdk/#span-exporter
+[4]: https://opentelemetry.io/docs/reference/specification/trace/sdk/#id-generators
+[5]: https://opentelemetry.io/docs/instrumentation/go/manual/
+[6]: https://opentelemetry.io/docs/instrumentation/go/
+[9]: /tracing/trace_collection/trace_context_propagation/go/

layouts/partials/apm/apm-otel-instrumentation.html

@@ -23,6 +23,13 @@
  </div>
  </a>
  </div>
+ <div class="col">
+ <a class="card h-100" href="go">
+ <div class="card-body text-center py-2 px-1">
+ {{ partial "img.html" (dict "root" . "src" "integrations_logos/golang.png" "class" "img-fluid" "alt" "Go" "width" "400") }}
+ </div>
+ </a>
+ </div>
  <div class="col">
  <a class="card h-100" href="dotnet">
  <div class="card-body text-center py-2 px-1">