Code fix for issues open-telemetry#1623, open-telemetry#1622, open-te…

…lemetry#958

pkg/collector/reconcile/config_replace.go

@@ -17,6 +17,7 @@ package reconcile
 import (
 	"fmt"
 	"net/url"
+	"strings"
 
 	"github.com/mitchellh/mapstructure"
 	promconfig "github.com/prometheus/prometheus/config"
@@ -36,15 +37,18 @@ type Config struct {
 }
 
 func ReplaceConfig(instance v1alpha1.OpenTelemetryCollector) (string, error) {
+	// Check if TargetAllocator is enabled, if not, return the original config
 	if !instance.Spec.TargetAllocator.Enabled {
 		return instance.Spec.Config, nil
 	}
+
 	config, getStringErr := adapters.ConfigFromString(instance.Spec.Config)
 	if getStringErr != nil {
 		return "", getStringErr
 	}
 
-	promCfgMap, getCfgPromErr := ta.ConfigToPromConfig(instance.Spec.Config)
+	// Get the Prometheus config map with dollar signs replaced to ensure successful validation of Prometheus regex
+	promCfgMap, getCfgPromErr := ta.ReplaceDollarSignInPromConfig(instance.Spec.Config)
 	if getCfgPromErr != nil {
 		return "", getCfgPromErr
 	}
@@ -62,21 +66,38 @@ func ReplaceConfig(instance v1alpha1.OpenTelemetryCollector) (string, error) {
 		return "", fmt.Errorf("error unmarshaling YAML: %w", marshalErr)
 	}
 
-	for i := range cfg.PromConfig.ScrapeConfigs {
-		escapedJob := url.QueryEscape(cfg.PromConfig.ScrapeConfigs[i].JobName)
-		cfg.PromConfig.ScrapeConfigs[i].ServiceDiscoveryConfigs = discovery.Configs{
-			&http.SDConfig{
-				URL: fmt.Sprintf("http://%s:80/jobs/%s/targets?collector_id=$POD_NAME", naming.TAService(instance), escapedJob),
-			},
+	// Escapes default replacement key added by prometheus and resets all other replacement keys to their original values
+	replacer := strings.NewReplacer(
+		"$", "$$",
+		"__DOUBLE_DOLLAR__", "$$",
+		"__SINGLE_DOLLAR__", "$",
+	)
+
+	// Loop through the scrape configs and escape "$" characters in relabel_configs and metric_relabel_configs
+	for _, scrapeCfg := range cfg.PromConfig.ScrapeConfigs {
+		for _, relabelCfg := range scrapeCfg.RelabelConfigs {
+			relabelCfg.Replacement = replacer.Replace(relabelCfg.Replacement)
+		}
+		for _, metricRelabelCfg := range scrapeCfg.MetricRelabelConfigs {
+			metricRelabelCfg.Replacement = replacer.Replace(metricRelabelCfg.Replacement)
+		}
+		// Escape the job name for use in the URL
+		escapedJob := url.QueryEscape(scrapeCfg.JobName)
+		// Create the service discovery configuration with the formatted URL
+		sdConfig := &http.SDConfig{
+			URL: fmt.Sprintf("http://%s:80/jobs/%s/targets?collector_id=$POD_NAME", naming.TAService(instance), escapedJob),
 		}
+		scrapeCfg.ServiceDiscoveryConfigs = discovery.Configs{sdConfig}
 	}
 
+	// Decode the Config struct back to a map and update the Prometheus config map
 	updPromCfgMap := make(map[string]interface{})
 	if err := mapstructure.Decode(cfg, &updPromCfgMap); err != nil {
 		return "", err
 	}
 
-	// type coercion checks are handled in the ConfigToPromConfig method above
+	// Update the OpenTelemetryCollector instance's config with the updated Prometheus config map
+	// type coercion checks are handled in the ReplaceDollarSignInPromConfig method above
 	config["receivers"].(map[interface{}]interface{})["prometheus"].(map[interface{}]interface{})["config"] = updPromCfgMap["PromConfig"]
 
 	out, err := yaml.Marshal(config)

pkg/collector/reconcile/config_replace_test.go

@@ -15,6 +15,7 @@
 package reconcile
 
 import (
+	"os"
 	"testing"
 
 	"github.com/prometheus/prometheus/discovery/http"
@@ -96,3 +97,31 @@ func TestPrometheusParser(t *testing.T) {
 	})
 
 }
+
+func TestRelabelConfig(t *testing.T) {
+	param, err := newParams("test/test-img", "../testdata/relabel_config_original.yaml")
+	assert.NoError(t, err)
+
+	t.Run("should escape $ characters in relabel configs replacement key", func(t *testing.T) {
+		expectedConfigBytes, err := os.ReadFile("../testdata/relabel_config_expected.yaml")
+		assert.NoError(t, err)
+		expectedConfig := string(expectedConfigBytes)
+
+		actualConfig, err := ReplaceConfig(param.Instance)
+		assert.NoError(t, err)
+
+		assert.Equal(t, expectedConfig, actualConfig)
+	})
+
+	t.Run("should not modify config when TargetAllocator is disabled", func(t *testing.T) {
+		param.Instance.Spec.TargetAllocator.Enabled = false
+		expectedConfigBytes, err := os.ReadFile("../testdata/relabel_config_original.yaml")
+		assert.NoError(t, err)
+		expectedConfig := string(expectedConfigBytes)
+
+		actualConfig, err := ReplaceConfig(param.Instance)
+		assert.NoError(t, err)
+
+		assert.Equal(t, expectedConfig, actualConfig)
+	})
+}

pkg/collector/reconcile/configmap.go

@@ -103,7 +103,7 @@ func desiredTAConfigMap(params Params) (corev1.ConfigMap, error) {
 		labels["app.kubernetes.io/version"] = "latest"
 	}
 
-	promConfig, err := ta.ConfigToPromConfig(params.Instance.Spec.Config)
+	promConfig, err := ta.ReplaceDollarSignInTAPromConfig(params.Instance.Spec.Config)
 	if err != nil {
 		return corev1.ConfigMap{}, err
 	}

pkg/collector/testdata/relabel_config_expected.yaml

@@ -0,0 +1,63 @@
+exporters:
+  logging: null
+processors: null
+receivers:
+  prometheus:
+    config:
+      global:
+        scrape_interval: 1m
+        scrape_timeout: 10s
+        evaluation_interval: 1m
+      scrape_configs:
+      - job_name: service-x
+        honor_timestamps: true
+        scrape_interval: 1m
+        scrape_timeout: 10s
+        metrics_path: /metrics
+        scheme: http
+        follow_redirects: true
+        enable_http2: true
+        relabel_configs:
+        - source_labels: [label1]
+          separator: ;
+          regex: (.*)
+          replacement: $$1
+          action: keep
+        - source_labels: [label2]
+          separator: ;
+          regex: (.*)
+          target_label: label3
+          replacement: $$1_$2
+          action: replace
+        - source_labels: [label4]
+          separator: ;
+          regex: (.*)
+          replacement: $$1
+          action: labelmap
+        - separator: ;
+          regex: foo_.*
+          replacement: $$1
+          action: labeldrop
+        metric_relabel_configs:
+        - source_labels: [label1]
+          separator: ;
+          regex: (.*)
+          replacement: $1
+          action: keep
+        - source_labels: [label4]
+          separator: ;
+          regex: (.*)
+          replacement: $$1
+          action: labelmap
+        http_sd_configs:
+        - follow_redirects: false
+          enable_http2: false
+          url: http://test-targetallocator:80/jobs/service-x/targets?collector_id=$POD_NAME
+service:
+  pipelines:
+    metrics:
+      exporters:
+      - logging
+      processors: []
+      receivers:
+      - prometheus

pkg/collector/testdata/relabel_config_original.yaml

@@ -0,0 +1,54 @@
+exporters:
+  logging: null
+processors: null
+receivers:
+  prometheus:
+    config:
+      global:
+        scrape_interval: 1m
+        scrape_timeout: 10s
+        evaluation_interval: 1m
+      scrape_configs:
+      - job_name: service-x
+        honor_timestamps: true
+        scrape_interval: 1m
+        scrape_timeout: 10s
+        metrics_path: /metrics
+        scheme: http
+        follow_redirects: true
+        enable_http2: true
+        relabel_configs:
+        - source_labels: [label1]
+          regex: (.*)
+          action: keep
+        - source_labels: [label2]
+          separator: ;
+          regex: (.*)
+          target_label: label3
+          replacement: $$1_$2
+          action: replace
+        - source_labels: [label4]
+          separator: ;
+          regex: (.*)
+          replacement: $$1
+          action: labelmap
+        - regex: foo_.*
+          action: labeldrop
+        metric_relabel_configs:
+        - source_labels: [label1]
+          separator: ;
+          regex: (.*)
+          replacement: $1
+          action: keep
+        - source_labels: [label4]
+          separator: ;
+          regex: (.*)
+          action: labelmap
+service:
+  pipelines:
+    metrics:
+      exporters:
+      - logging
+      processors: []
+      receivers:
+      - prometheus