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# "Passthrough" setup for OpenTelemetry
Some Go programs may wish to propagate context without recording spans. To do this in OpenTelemetry, simply install `TextMapPropagators`, but do not install a TracerProvider using the SDK. This works because the default TracerProvider implementation returns a "Non-Recording" span that keeps the context of the caller but does not record spans.
For example, when you initialize your global settings, the following will propagate context without recording spans:
```golang
// Setup Propagators only
otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(propagation.TraceContext{}, propagation.Baggage{}))
```
But the following will propagate context _and_ create new, potentially recorded spans:
```golang
// Setup SDK
exp, _ := stdout.New(stdout.WithPrettyPrint())
tp = sdktrace.NewTracerProvider(
sdktrace.WithBatcher(exp),
)
otel.SetTracerProvider(tp)
// Setup Propagators
otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(propagation.TraceContext{}, propagation.Baggage{}))
```
## The Demo
The demo has the following call structure:
`Outer -> Passthrough -> Inner`
If all components had both an SDK and propagators registered, we would expect the trace to look like:
```
|-------outer---------|
|-Passthrough recv-|
|Passthrough send|
|---inner---|
```
However, in this demo, only the outer and inner have TracerProvider backed by the SDK. All components have Propagators set. In this case, we expect to see:
```
|-------outer---------|
|---inner---|
```
|
