Update default span/transaction type for OTel

[axw]

Motivation/summary

Align OpenTelemetry span type/subtype with the agent bridge spec:

• default to app.internal for internal spans
• default to unknown for non-internal spans
• default to unknown for transactions
• remove the special ${component} attribute handling

Checklist

• Update CHANGELOG.asciidoc
  - [ ] Update package changelog.yml (only if changes to apmpackage have been made)
  - [ ] Documentation has been updated

How to test these changes

1. Send some custom internal OTLP spans, check they get type "app", subtype "internal".
2. Send some custom non-internal OTLP spans, check they get type "unknown"

Related issues

Closes #6543

[apmmachine]

❕ Build Aborted

There is a new build on-going so the previous on-going builds have been aborted.

the below badges are clickable and redirect to their specific view in the CI or DOCS

Expand to view the summary

Build stats

• Reason: Aborted from #5

• Start Time: 2021-12-07T07:59:32.704+0000

• Duration: 43 min 34 sec

• Commit: cbbef8a

Test stats 🧪

Test	Results
Failed	0
Passed	5149
Skipped	18
Total	5167

Steps errors

Expand to view the steps failures

Print Message

• Took 0 min 0 sec . View more details here
• Description: �[39;49m[INFO] Can not determine redirect link!!!�[0m

🤖 GitHub comments

To re-run your PR in the CI, just comment with:

• /test : Re-trigger the build.

• /hey-apm : Run the hey-apm benchmark.

• /package : Generate and publish the docker images.

• run elasticsearch-ci/docs : Re-trigger the docs validation. (use unformatted text in the comment!)

[apmmachine]

❕ Build Aborted

Either there was a build timeout or someone aborted the build.

the below badges are clickable and redirect to their specific view in the CI or DOCS

Expand to view the summary

Build stats

• Start Time: 2021-12-07T08:38:54.695+0000

• Duration: 123 min 0 sec

• Commit: 9606dc1

Test stats 🧪

Test	Results
Failed	0
Passed	4356
Skipped	15
Total	4371

🤖 GitHub comments

To re-run your PR in the CI, just comment with:

• /test : Re-trigger the build.

• /hey-apm : Run the hey-apm benchmark.

• /package : Generate and publish the docker images.

• run elasticsearch-ci/docs : Re-trigger the docs validation. (use unformatted text in the comment!)

[stuartnelson3]

Confirmed with 50edba1

package main

import (
	"context"
	"log"

	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/exporters/otlp"
	"go.opentelemetry.io/otel/exporters/otlp/otlpgrpc"
	"go.opentelemetry.io/otel/propagation"
	"go.opentelemetry.io/otel/sdk/resource"
	sdktrace "go.opentelemetry.io/otel/sdk/trace"
	oteltrace "go.opentelemetry.io/otel/trace"
)

var tracer = otel.Tracer("mux-server")

func main() {
	tp := initTracer()
	defer func() {
		if err := tp.Shutdown(context.Background()); err != nil {
			log.Printf("Error shutting down tracer provider: %v", err)
		}
	}()
	// Change SpanKind here.
	_, span := tracer.Start(context.Background(), "span", oteltrace.WithSpanKind(oteltrace.SpanKindClient))
	defer span.End()
}

func initTracer() *sdktrace.TracerProvider {
	ctx := context.Background()

	endpoint := "localhost:8200"
	driver := otlpgrpc.NewDriver(
		otlpgrpc.WithInsecure(),
		otlpgrpc.WithEndpoint(endpoint),
	)
	exporter, err := otlp.NewExporter(ctx, driver)
	if err != nil {
		log.Fatal(err)
	}

	resources := resource.NewWithAttributes(
		attribute.String("host.name", "slaptop"),
	)
	tp := sdktrace.NewTracerProvider(
		sdktrace.WithSampler(sdktrace.AlwaysSample()),
		sdktrace.WithBatcher(exporter),
		sdktrace.WithResource(resources),
	)
	otel.SetTracerProvider(tp)
	otel.SetTextMapPropagator(
		propagation.NewCompositeTextMapPropagator(
			propagation.TraceContext{},
			propagation.Baggage{},
		),
	)
	return tp
}