[receiver/prometheusreceiver] Configuring httpSD http client from TAs clienthttp

.chloggen/httpSD-client-config-from-TA-confighttp.yaml

@@ -0,0 +1,28 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: prometheusreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Use confighttp for httpSD client config
+
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [33370]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

receiver/prometheusreceiver/metrics_receiver.go

@@ -6,6 +6,7 @@ package prometheusreceiver // import "github.com/open-telemetry/opentelemetry-co
 import (
 	"bytes"
 	"context"
+	"encoding/base64"
 	"errors"
 	"fmt"
 	"hash/fnv"
@@ -16,6 +17,7 @@ import (
 	"reflect"
 	"regexp"
 	"sort"
+	"strings"
 	"sync"
 	"time"
 	"unsafe"
@@ -173,6 +175,80 @@ func getScrapeConfigHash(jobToScrapeConfig map[string]*config.ScrapeConfig) (uin
 	return hash.Sum64(), err
 }
 
+// ConvertTLSVersion converts a string TLS version to the corresponding config.TLSVersion value in prometheus common.
+func convertTLSVersion(version string) (commonconfig.TLSVersion, error) {
+	normalizedVersion := "TLS" + strings.ReplaceAll(version, ".", "")
+
+	if tlsVersion, exists := commonconfig.TLSVersions[normalizedVersion]; exists {
+		return tlsVersion, nil
+	}
+	return 0, fmt.Errorf("unsupported TLS version: %s", version)
+}
+
+// configureSDHTTPClientConfig configures the http client for the service discovery manager
+// based on the provided TargetAllocator configuration.
+func configureSDHTTPClientConfigFromTA(httpSD *promHTTP.SDConfig, allocConf *TargetAllocator) error {
+	httpSD.HTTPClientConfig.FollowRedirects = false
+
+	httpSD.HTTPClientConfig.TLSConfig = commonconfig.TLSConfig{
+		InsecureSkipVerify: allocConf.TLSSetting.InsecureSkipVerify,
+		ServerName:         allocConf.TLSSetting.ServerName,
+		CAFile:             allocConf.TLSSetting.CAFile,
+		CertFile:           allocConf.TLSSetting.CertFile,
+		KeyFile:            allocConf.TLSSetting.KeyFile,
+	}
+
+	if allocConf.TLSSetting.CAPem != "" {
+		decodedCA, err := base64.StdEncoding.DecodeString(string(allocConf.TLSSetting.CAPem))
+		if err != nil {
+			return fmt.Errorf("failed to decode CA: %w", err)
+		}
+		httpSD.HTTPClientConfig.TLSConfig.CA = string(decodedCA)
+	}
+
+	if allocConf.TLSSetting.CertPem != "" {
+		decodedCert, err := base64.StdEncoding.DecodeString(string(allocConf.TLSSetting.CertPem))
+		if err != nil {
+			return fmt.Errorf("failed to decode Cert: %w", err)
+		}
+		httpSD.HTTPClientConfig.TLSConfig.Cert = string(decodedCert)
+	}
+
+	if allocConf.TLSSetting.KeyPem != "" {
+		decodedKey, err := base64.StdEncoding.DecodeString(string(allocConf.TLSSetting.KeyPem))
+		if err != nil {
+			return fmt.Errorf("failed to decode Key: %w", err)
+		}
+		httpSD.HTTPClientConfig.TLSConfig.Key = commonconfig.Secret(decodedKey)
+	}
+
+	if allocConf.TLSSetting.MinVersion != "" {
+		minVersion, err := convertTLSVersion(allocConf.TLSSetting.MinVersion)
+		if err != nil {
+			return err
+		}
+		httpSD.HTTPClientConfig.TLSConfig.MinVersion = minVersion
+	}
+
+	if allocConf.TLSSetting.MaxVersion != "" {
+		maxVersion, err := convertTLSVersion(allocConf.TLSSetting.MaxVersion)
+		if err != nil {
+			return err
+		}
+		httpSD.HTTPClientConfig.TLSConfig.MaxVersion = maxVersion
+	}
+
+	if allocConf.ProxyURL != "" {
+		proxyURL, err := url.Parse(allocConf.ProxyURL)
+		if err != nil {
+			return err
+		}
+		httpSD.HTTPClientConfig.ProxyURL = commonconfig.URL{URL: proxyURL}
+	}
+
+	return nil
+}
+
 // syncTargetAllocator request jobs from targetAllocator and update underlying receiver, if the response does not match the provided compareHash.
 // baseDiscoveryCfg can be used to provide additional ScrapeConfigs which will be added to the retrieved jobs.
 func (r *pReceiver) syncTargetAllocator(compareHash uint64, allocConf *TargetAllocator, baseCfg *PromConfig) (uint64, error) {
@@ -207,7 +283,13 @@ func (r *pReceiver) syncTargetAllocator(compareHash uint64, allocConf *TargetAll
 		}
 		escapedJob := url.QueryEscape(jobName)
 		httpSD.URL = fmt.Sprintf("%s/jobs/%s/targets?collector_id=%s", allocConf.Endpoint, escapedJob, allocConf.CollectorID)
-		httpSD.HTTPClientConfig.FollowRedirects = false
+
+		err = configureSDHTTPClientConfigFromTA(&httpSD, allocConf)
+		if err != nil {
+			r.settings.Logger.Error("Failed to configure http client config", zap.Error(err))
+			return 0, err
+		}
+
 		scrapeConfig.ServiceDiscoveryConfigs = discovery.Configs{
 			&httpSD,
 		}

receiver/prometheusreceiver/metrics_receiver_target_allocator_test.go

@@ -7,9 +7,11 @@ package prometheusreceiver
 
 import (
 	"context"
+	"encoding/base64"
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
+	"net/url"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -24,6 +26,8 @@ import (
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.opentelemetry.io/collector/component/componenttest"
+	"go.opentelemetry.io/collector/config/configopaque"
+	"go.opentelemetry.io/collector/config/configtls"
 	"go.opentelemetry.io/collector/consumer/consumertest"
 	"go.opentelemetry.io/collector/receiver/receivertest"
 )
@@ -776,3 +780,51 @@ func TestTargetAllocatorJobRetrieval(t *testing.T) {
 		})
 	}
 }
+
+func TestConfigureSDHTTPClientConfigFromTA(t *testing.T) {
+	ta := &TargetAllocator{}
+	ta.TLSSetting = configtls.ClientConfig{
+		InsecureSkipVerify: true,
+		ServerName:         "test.server",
+		Config: configtls.Config{
+			CAFile:     "/path/to/ca",
+			CertFile:   "/path/to/cert",
+			KeyFile:    "/path/to/key",
+			CAPem:      configopaque.String(base64.StdEncoding.EncodeToString([]byte("test-ca"))),
+			CertPem:    configopaque.String(base64.StdEncoding.EncodeToString([]byte("test-cert"))),
+			KeyPem:     configopaque.String(base64.StdEncoding.EncodeToString([]byte("test-key"))),
+			MinVersion: "1.2",
+			MaxVersion: "1.3",
+		},
+	}
+	ta.ProxyURL = "http://proxy.test"
+
+	httpSD := &promHTTP.SDConfig{RefreshInterval: model.Duration(30 * time.Second)}
+
+	err := configureSDHTTPClientConfigFromTA(httpSD, ta)
+
+	assert.NoError(t, err)
+
+	assert.Equal(t, false, httpSD.HTTPClientConfig.FollowRedirects)
+	assert.Equal(t, true, httpSD.HTTPClientConfig.TLSConfig.InsecureSkipVerify)
+	assert.Equal(t, "test.server", httpSD.HTTPClientConfig.TLSConfig.ServerName)
+	assert.Equal(t, "/path/to/ca", httpSD.HTTPClientConfig.TLSConfig.CAFile)
+	assert.Equal(t, "/path/to/cert", httpSD.HTTPClientConfig.TLSConfig.CertFile)
+	assert.Equal(t, "/path/to/key", httpSD.HTTPClientConfig.TLSConfig.KeyFile)
+	assert.Equal(t, "test-ca", httpSD.HTTPClientConfig.TLSConfig.CA)
+	assert.Equal(t, "test-cert", httpSD.HTTPClientConfig.TLSConfig.Cert)
+	assert.Equal(t, commonconfig.Secret("test-key"), httpSD.HTTPClientConfig.TLSConfig.Key)
+	assert.Equal(t, commonconfig.TLSVersions["TLS12"], httpSD.HTTPClientConfig.TLSConfig.MinVersion)
+	assert.Equal(t, commonconfig.TLSVersions["TLS13"], httpSD.HTTPClientConfig.TLSConfig.MaxVersion)
+
+	parsedProxyURL, _ := url.Parse("http://proxy.test")
+	assert.Equal(t, commonconfig.URL{URL: parsedProxyURL}, httpSD.HTTPClientConfig.ProxyURL)
+
+	// Test case with empty TargetAllocator
+	emptyTA := &TargetAllocator{}
+	emptyHTTPSD := &promHTTP.SDConfig{RefreshInterval: model.Duration(30 * time.Second)}
+
+	err = configureSDHTTPClientConfigFromTA(emptyHTTPSD, emptyTA)
+
+	assert.NoError(t, err)
+}