fix(otel): normalize OTEL endpoint env vars to prevent SDK parse errors

commons/opentelemetry/otel.go

@@ -8,6 +8,7 @@ import (
 	"fmt"
 	"maps"
 	"net/http"
+	"os"
 	"reflect"
 	"strconv"
 	"strings"
@@ -99,6 +100,7 @@ func NewTelemetry(cfg TelemetryConfig) (*Telemetry, error) {
 	}
 
 	normalizeEndpoint(&cfg)
+	normalizeEndpointEnvVars()
 
 	if cfg.EnableTelemetry && strings.TrimSpace(cfg.CollectorExporterEndpoint) == "" {
 		return handleEmptyEndpoint(cfg)
@@ -143,6 +145,25 @@ func normalizeEndpoint(cfg *TelemetryConfig) {
 	}
 }
 
+// normalizeEndpointEnvVars ensures OTEL exporter endpoint environment variables
+// contain a URL scheme. The OTEL SDK's envconfig reads these via url.Parse(),
+// which fails on bare "host:port" values. Adding "http://" prevents noisy
+// "parse url" errors from the SDK's internal logger.
+func normalizeEndpointEnvVars() {
+	for _, key := range []string{
+		"OTEL_EXPORTER_OTLP_ENDPOINT",
+		"OTEL_EXPORTER_OTLP_TRACES_ENDPOINT",
+		"OTEL_EXPORTER_OTLP_METRICS_ENDPOINT",
+	} {
+		v := strings.TrimSpace(os.Getenv(key))
+		if v == "" || strings.HasPrefix(v, "http://") || strings.HasPrefix(v, "https://") {
+			continue
+		}
+
+		_ = os.Setenv(key, "http://"+v)
+	}
+}
+
 // handleEmptyEndpoint handles the case where telemetry is enabled but the collector
 // endpoint is empty, returning noop providers installed as globals.
 func handleEmptyEndpoint(cfg TelemetryConfig) (*Telemetry, error) {

commons/opentelemetry/otel_test.go

@@ -4,6 +4,7 @@ package opentelemetry
 
 import (
 	"context"
+	"os"
 	"strings"
 	"testing"
 
@@ -196,6 +197,89 @@ func TestNewTelemetry_EndpointNormalization(t *testing.T) {
 	}
 }
 
+// ===========================================================================
+// 1c. Endpoint environment variable normalization
+// ===========================================================================
+
+func TestNormalizeEndpointEnvVars(t *testing.T) {
+	envKeys := []string{
+		"OTEL_EXPORTER_OTLP_ENDPOINT",
+		"OTEL_EXPORTER_OTLP_TRACES_ENDPOINT",
+		"OTEL_EXPORTER_OTLP_METRICS_ENDPOINT",
+	}
+
+	tests := []struct {
+		name     string
+		value    string
+		set      bool
+		expected string
+	}{
+		{
+			name:     "bare host:port gets http scheme",
+			value:    "10.10.0.202:4317",
+			set:      true,
+			expected: "http://10.10.0.202:4317",
+		},
+		{
+			name:     "hostname:port gets http scheme",
+			value:    "otel-collector:4317",
+			set:      true,
+			expected: "http://otel-collector:4317",
+		},
+		{
+			name:     "http scheme preserved",
+			value:    "http://otel-collector:4317",
+			set:      true,
+			expected: "http://otel-collector:4317",
+		},
+		{
+			name:     "https scheme preserved",
+			value:    "https://otel-collector:4317",
+			set:      true,
+			expected: "https://otel-collector:4317",
+		},
+		{
+			name:     "whitespace trimmed before adding scheme",
+			value:    "  10.10.0.202:4317  ",
+			set:      true,
+			expected: "http://10.10.0.202:4317",
+		},
+		{
+			name:     "empty value skipped",
+			value:    "",
+			set:      true,
+			expected: "",
+		},
+		{
+			name:     "whitespace-only value skipped",
+			value:    "   ",
+			set:      true,
+			expected: "   ",
+		},
+		{
+			name:     "unset env var skipped",
+			value:    "",
+			set:      false,
+			expected: "",
+		},
+	}
+
+	for _, tt := range tests {
+		for _, key := range envKeys {
+			t.Run(tt.name+"/"+key, func(t *testing.T) {
+				if tt.set {
+					t.Setenv(key, tt.value)
+				}
+
+				normalizeEndpointEnvVars()
+
+				got := os.Getenv(key)
+				assert.Equal(t, tt.expected, got)
+			})
+		}
+	}
+}
+
 // ===========================================================================
 // 2. Telemetry methods on nil receiver
 // ===========================================================================