Add custom log source support

[mackjmr]

What does this PR do?

This PR adds support to setting the log source via resource attribute OR log attribute datadog.log.source. If this is not set, it falls back to the previous behaviour (hardcoded log source).

This change is applied in all three paths:

• OTLP ingest in agent
• Datadog Exporter
• Converged agent

Motivation

Additional Notes

Possible Drawbacks / Trade-offs

Describe how to test/QA your changes

Resource attribute:
Set resource attribute datadog.log.source and send logs. Ensure the source is being populated in the app.

Log attribute:
Set log attribute datadog.log.source and send logs. Ensure the source is being populated in the app.

You can use the following app to emit the logs:

package main

import (
	"context"
	"fmt"
	"time"

	// "go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp"
	logapi "go.opentelemetry.io/otel/log"
	"go.opentelemetry.io/otel/log/global"
	"go.opentelemetry.io/otel/sdk/log"
	"go.opentelemetry.io/otel/sdk/resource"
	semconv "go.opentelemetry.io/otel/semconv/v1.26.0"
)

func main() {
	ctx := context.Background()

	// Create resource.
	res, err := newResource()
	if err != nil {
		panic(err)
	}

	// Create a logger provider.
	// You can pass this instance directly when creating bridges.
	loggerProvider, err := newLoggerProvider(ctx, res)
	if err != nil {
		panic(err)
	}

	// Handle shutdown properly so nothing leaks.
	defer func() {
		if err := loggerProvider.Shutdown(ctx); err != nil {
			fmt.Println(err)
		}
	}()

	global.SetLoggerProvider(loggerProvider)
	logger := loggerProvider.Logger("otel_logger")
	record := logapi.Record{}
	// record.AddAttributes(logapi.String("datadog.log.source", "customsrc"))

	record.SetBody(logapi.StringValue("THIS IS THE BODY"))
	for {
		logger.Emit(context.Background(), record)
		time.Sleep(5 * time.Second)
	}
}

func newResource() (*resource.Resource, error) {
	return resource.Merge(resource.Default(),
		resource.NewWithAttributes(semconv.SchemaURL,
			semconv.ServiceName("my-service"),
			semconv.ServiceVersion("0.1.0"),
			attribute.String("datadog.log.source", "customsrc"),
		))
}

func newLoggerProvider(ctx context.Context, res *resource.Resource) (*log.LoggerProvider, error) {
	exporter, err := otlploghttp.New(ctx, otlploghttp.WithInsecure())
	if err != nil {
		return nil, err
	}
	processor := log.NewBatchProcessor(exporter)
	provider := log.NewLoggerProvider(
		log.WithResource(res),
		log.WithProcessor(processor),
	)
	return provider, nil
}

[pr-commenter]

Test changes on VM

Use this command from test-infra-definitions to manually test this PR changes on a VM:

inv create-vm --pipeline-id=43256912 --os-family=ubuntu

Note: This applies to commit 89f9d4b

[pr-commenter]

Regression Detector

Regression Detector Results

Run ID: 0b4c6fcd-19c2-4360-aaee-494e8f5e6622 Metrics dashboard Target profiles

Baseline: 7f04426
Comparison: fe16b1d

Performance changes are noted in the perf column of each table:

• ✅ = significantly better comparison variant performance
• ❌ = significantly worse comparison variant performance
• ➖ = no significant change in performance

No significant changes in experiment optimization goals

Confidence level: 90.00%
Effect size tolerance: |Δ mean %| ≥ 5.00%

There were no significant changes in experiment optimization goals at this confidence level and effect size tolerance.

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	links
➖	idle	memory utilization	+0.14	[+0.10, +0.17]	Logs
➖	uds_dogstatsd_to_api	ingress throughput	+0.00	[-0.00, +0.00]	Logs
➖	tcp_dd_logs_filter_exclude	ingress throughput	-0.00	[-0.01, +0.01]	Logs
➖	pycheck_lots_of_tags	% cpu utilization	-0.01	[-2.47, +2.44]	Logs
➖	otel_to_otel_logs	ingress throughput	-0.24	[-1.05, +0.58]	Logs
➖	uds_dogstatsd_to_api_cpu	% cpu utilization	-0.37	[-1.16, +0.42]	Logs
➖	basic_py_check	% cpu utilization	-0.48	[-3.08, +2.11]	Logs
➖	file_tree	memory utilization	-0.72	[-0.81, -0.63]	Logs
➖	tcp_syslog_to_blackhole	ingress throughput	-2.60	[-14.88, +9.69]	Logs

Bounds Checks

perf	experiment	bounds_check_name	replicates_passed
✅	idle	memory_usage	10/10

Explanation

A regression test is an A/B test of target performance in a repeatable rig, where "performance" is measured as "comparison variant minus baseline variant" for an optimization goal (e.g., ingress throughput). Due to intrinsic variability in measuring that goal, we can only estimate its mean value for each experiment; we report uncertainty in that value as a 90.00% confidence interval denoted "Δ mean % CI".

For each experiment, we decide whether a change in performance is a "regression" -- a change worth investigating further -- if all of the following criteria are true:

1. Its estimated |Δ mean %| ≥ 5.00%, indicating the change is big enough to merit a closer look.

2. Its 90.00% confidence interval "Δ mean % CI" does not contain zero, indicating that if our statistical model is accurate, there is at least a 90.00% chance there is a difference in performance between baseline and comparison variants.

3. Its configuration does not mark it "erratic".

[songy23]

LGTM

[mackjmr]

/merge

[dd-devflow]

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[dd-devflow]

🚂 MergeQueue: pull request added to the queue

The median merge time in main is 22m.

Use /merge -c to cancel this operation!