[prometheus] Use OTEL helper instead of tlscfg package (#6266)

## Which problem is this PR solving?
- Part of #4316 

## Description of the changes
- 

## How was this change tested?
- 

## Checklist
- [ ] I have read
https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
- [ ] I have signed all commits
- [ ] I have added unit tests for the new functionality
- [ ] I have run lint and test steps successfully
  - for `jaeger`: `make lint test`
  - for `jaeger-ui`: `yarn lint` and `yarn test`

---------

Signed-off-by: chahatsagarmain <[email protected]>
Signed-off-by: chahat sagar <[email protected]>
Co-authored-by: Yuri Shkuro <[email protected]>

pkg/prometheus/config/config.go

@@ -7,15 +7,14 @@ import (
 	"time"
 
 	"github.com/asaskevich/govalidator"
-
-	"github.com/jaegertracing/jaeger/pkg/config/tlscfg"
+	"go.opentelemetry.io/collector/config/configtls"
 )
 
 // Configuration describes the options to customize the storage behavior.
 type Configuration struct {
 	ServerURL      string        `valid:"required" mapstructure:"endpoint"`
 	ConnectTimeout time.Duration `mapstructure:"connect_timeout"`
-	TLS            tlscfg.Options
+	TLS            configtls.ClientConfig
 
 	TokenFilePath            string `mapstructure:"token_file_path"`
 	TokenOverrideFromContext bool   `mapstructure:"token_override_from_context"`

plugin/metrics/prometheus/metricsstore/reader.go

@@ -5,7 +5,6 @@ package metricsstore
 
 import (
 	"context"
-	"crypto/tls"
 	"fmt"
 	"net"
 	"net/http"
@@ -315,12 +314,10 @@ func logErrorToSpan(span trace.Span, err error) {
 	span.SetStatus(codes.Error, err.Error())
 }
 
-func getHTTPRoundTripper(c *config.Configuration, logger *zap.Logger) (rt http.RoundTripper, err error) {
-	var ctlsConfig *tls.Config
-	if c.TLS.Enabled {
-		if ctlsConfig, err = c.TLS.Config(logger); err != nil {
-			return nil, err
-		}
+func getHTTPRoundTripper(c *config.Configuration, _ *zap.Logger) (rt http.RoundTripper, err error) {
+	ctlsConfig, err := c.TLS.LoadTLSConfig(context.Background())
+	if err != nil {
+		return nil, err
 	}
 	// KeepAlive and TLSHandshake timeouts are kept to existing Prometheus client's
 	// DefaultRoundTripper to simplify user configuration and may be made configurable when required.

plugin/metrics/prometheus/metricsstore/reader_test.go

@@ -18,14 +18,14 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"go.opentelemetry.io/collector/config/configtls"
 	"go.opentelemetry.io/otel/codes"
 	sdktrace "go.opentelemetry.io/otel/sdk/trace"
 	"go.opentelemetry.io/otel/sdk/trace/tracetest"
 	"go.opentelemetry.io/otel/trace"
 	"go.uber.org/zap"
 
 	"github.com/jaegertracing/jaeger/pkg/bearertoken"
-	"github.com/jaegertracing/jaeger/pkg/config/tlscfg"
 	"github.com/jaegertracing/jaeger/pkg/prometheus/config"
 	"github.com/jaegertracing/jaeger/pkg/testutils"
 	"github.com/jaegertracing/jaeger/proto-gen/api_v2/metrics"
@@ -739,13 +739,10 @@ func TestGetRoundTripperTLSConfig(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			logger := zap.NewNop()
 			config := &config.Configuration{
-				ConnectTimeout: 9 * time.Millisecond,
-				TLS: tlscfg.Options{
-					Enabled: tc.tlsEnabled,
-				},
+				ConnectTimeout:           9 * time.Millisecond,
+				TLS:                      configtls.ClientConfig{},
 				TokenOverrideFromContext: true,
 			}
-			defer config.TLS.Close()
 			rt, err := getHTTPRoundTripper(config, logger)
 			require.NoError(t, err)
 
@@ -856,9 +853,10 @@ func TestInvalidCertFile(t *testing.T) {
 	reader, err := NewMetricsReader(config.Configuration{
 		ServerURL:      "https://localhost:1234",
 		ConnectTimeout: defaultTimeout,
-		TLS: tlscfg.Options{
-			Enabled: true,
-			CAPath:  "foo",
+		TLS: configtls.ClientConfig{
+			Config: configtls.Config{
+				CAFile: "foo",
+			},
 		},
 	}, logger, tracer)
 	require.Error(t, err)

plugin/metrics/prometheus/options.go

@@ -44,6 +44,8 @@ type Options struct {
 	config.Configuration `mapstructure:",squash"`
 }
 
+var tlsFlagsCfg = tlscfg.ClientFlagsConfig{Prefix: prefix}
+
 func DefaultConfig() config.Configuration {
 	return config.Configuration{
 		ServerURL:      defaultServerURL,
@@ -64,7 +66,7 @@ func NewOptions() *Options {
 }
 
 // AddFlags from this storage to the CLI.
-func (opt *Options) AddFlags(flagSet *flag.FlagSet) {
+func (*Options) AddFlags(flagSet *flag.FlagSet) {
 	flagSet.String(prefix+suffixServerURL, defaultServerURL,
 		"The Prometheus server's URL, must include the protocol scheme e.g. http://localhost:9090")
 	flagSet.Duration(prefix+suffixConnectTimeout, defaultConnectTimeout,
@@ -92,7 +94,7 @@ func (opt *Options) AddFlags(flagSet *flag.FlagSet) {
 			`For example: `+
 			`"duration_bucket" (not normalized) -> "duration_milliseconds_bucket (normalized)"`)
 
-	opt.getTLSFlagsConfig().AddFlags(flagSet)
+	tlsFlagsCfg.AddFlags(flagSet)
 }
 
 // InitFromViper initializes the options struct with values from Viper.
@@ -113,19 +115,14 @@ func (opt *Options) InitFromViper(v *viper.Viper) error {
 	}
 
 	var err error
-	opt.TLS, err = opt.getTLSFlagsConfig().InitFromViper(v)
+	tlsOpts, err := tlsFlagsCfg.InitFromViper(v)
 	if err != nil {
 		return fmt.Errorf("failed to process Prometheus TLS options: %w", err)
 	}
+	opt.TLS = tlsOpts.ToOtelClientConfig()
 	return nil
 }
 
-func (*Options) getTLSFlagsConfig() tlscfg.ClientFlagsConfig {
-	return tlscfg.ClientFlagsConfig{
-		Prefix: prefix,
-	}
-}
-
 // stripWhiteSpace removes all whitespace characters from a string.
 func stripWhiteSpace(str string) string {
 	return strings.ReplaceAll(str, " ", "")