Merge branch 'main' into david.ogbureke/add-lambda-readme

Author: Dogbu-cyber

internal/appsec/listener/httpsec/roundtripper.go

@@ -71,7 +71,7 @@ func (feature *DownwardRequestFeature) OnStart(op *httpsec.RoundTripOperation, a
 	builder := addresses.NewAddressesBuilder().
 		WithDownwardURL(args.URL).
 		WithDownwardMethod(args.Method).
-		WithDownwardRequestHeaders(args.Headers)
+		WithDownwardRequestHeaders(headersToLower(args.Headers))
 
 	// Increment the span metric for downward requests
 	op.HandlerOp.ContextOperation.GetMetricsInstance().SumDownstreamRequestsCalls.Add(1)

internal/appsec/testdata/api10.json

@@ -413,7 +413,7 @@
               {
                 "address": "server.io.net.request.headers",
                 "key_path": [
-                  "Witness"
+                  "witness"
                 ]
               }
             ],

internal/config/config.go

@@ -166,24 +166,24 @@ func loadConfig() *Config {
 		}
 	}
 
-	hostname, err := os.Hostname()
-	if err != nil {
-		log.Warn("unable to look up hostname: %s", err.Error())
-		cfg.hostnameLookupError = err
+	// Hostname lookup, if DD_TRACE_REPORT_HOSTNAME is true
+	// If the hostname lookup fails, an error is set and the hostname is not reported
+	// The tracer will fail to start if the hostname lookup fails when it is explicitly configured
+	// to report the hostname.
+	if provider.getBool("DD_TRACE_REPORT_HOSTNAME", false) {
+		hostname, err := os.Hostname()
+		if err != nil {
+			log.Warn("unable to look up hostname: %s", err.Error())
+			cfg.hostnameLookupError = err
+		}
+		cfg.hostname = hostname
+		cfg.reportHostname = true
 	}
-
-	// Always read DD_TRACE_REPORT_HOSTNAME for telemetry tracking
-	reportHostnameFromEnv := provider.getBool("DD_TRACE_REPORT_HOSTNAME", false)
-
-	// Check if DD_TRACE_SOURCE_HOSTNAME was explicitly set
+	// Check if DD_TRACE_SOURCE_HOSTNAME was explicitly set, it takes precedence over the hostname lookup
 	if sourceHostname, ok := env.Lookup("DD_TRACE_SOURCE_HOSTNAME"); ok {
 		// Explicitly configured hostname - always report it
 		cfg.hostname = sourceHostname
 		cfg.reportHostname = true
-	} else if err == nil {
-		// Auto-detected hostname - only report if DD_TRACE_REPORT_HOSTNAME=true
-		cfg.hostname = hostname
-		cfg.reportHostname = reportHostnameFromEnv
 	}
 
 	return cfg

internal/config/config_test.go

@@ -431,3 +431,85 @@ func TestSetServiceMappingReportsFullList(t *testing.T) {
 	sort.Strings(parts)
 	assert.Equal(t, []string{"a:3", "b:2"}, parts)
 }
+
+func TestHostnameConfiguration(t *testing.T) {
+	t.Run("default behavior - hostname empty when not configured", func(t *testing.T) {
+		resetGlobalState()
+		defer resetGlobalState()
+
+		cfg := Get()
+		require.NotNil(t, cfg)
+
+		assert.Empty(t, cfg.Hostname(), "Hostname should be empty by default")
+		assert.False(t, cfg.ReportHostname(), "ReportHostname should be false by default")
+	})
+
+	t.Run("DD_TRACE_REPORT_HOSTNAME=true enables hostname lookup", func(t *testing.T) {
+		resetGlobalState()
+		defer resetGlobalState()
+
+		t.Setenv("DD_TRACE_REPORT_HOSTNAME", "true")
+
+		cfg := Get()
+		require.NotNil(t, cfg)
+
+		assert.NotEmpty(t, cfg.Hostname(), "Hostname should be set when DD_TRACE_REPORT_HOSTNAME=true")
+		assert.True(t, cfg.ReportHostname(), "ReportHostname should be true when DD_TRACE_REPORT_HOSTNAME=true")
+		assert.NoError(t, cfg.HostnameLookupError(), "HostnameLookupError should be nil on successful lookup")
+	})
+
+	t.Run("DD_TRACE_REPORT_HOSTNAME=false keeps hostname empty", func(t *testing.T) {
+		resetGlobalState()
+		defer resetGlobalState()
+
+		t.Setenv("DD_TRACE_REPORT_HOSTNAME", "false")
+
+		cfg := Get()
+		require.NotNil(t, cfg)
+
+		assert.Empty(t, cfg.Hostname(), "Hostname should be empty when DD_TRACE_REPORT_HOSTNAME=false")
+		assert.False(t, cfg.ReportHostname(), "ReportHostname should be false when DD_TRACE_REPORT_HOSTNAME=false")
+	})
+
+	t.Run("DD_TRACE_SOURCE_HOSTNAME sets explicit hostname", func(t *testing.T) {
+		resetGlobalState()
+		defer resetGlobalState()
+
+		t.Setenv("DD_TRACE_SOURCE_HOSTNAME", "custom-hostname")
+
+		cfg := Get()
+		require.NotNil(t, cfg)
+
+		assert.Equal(t, "custom-hostname", cfg.Hostname(), "Hostname should match DD_TRACE_SOURCE_HOSTNAME")
+		assert.True(t, cfg.ReportHostname(), "ReportHostname should be true when DD_TRACE_SOURCE_HOSTNAME is set")
+	})
+
+	t.Run("DD_TRACE_SOURCE_HOSTNAME takes precedence over DD_TRACE_REPORT_HOSTNAME", func(t *testing.T) {
+		resetGlobalState()
+		defer resetGlobalState()
+
+		t.Setenv("DD_TRACE_REPORT_HOSTNAME", "true")
+		t.Setenv("DD_TRACE_SOURCE_HOSTNAME", "override-hostname")
+
+		cfg := Get()
+		require.NotNil(t, cfg)
+
+		assert.Equal(t, "override-hostname", cfg.Hostname(), "DD_TRACE_SOURCE_HOSTNAME should take precedence")
+		assert.True(t, cfg.ReportHostname(), "ReportHostname should be true")
+	})
+
+	t.Run("empty DD_TRACE_SOURCE_HOSTNAME is used when explicitly set", func(t *testing.T) {
+		resetGlobalState()
+		defer resetGlobalState()
+
+		t.Setenv("DD_TRACE_REPORT_HOSTNAME", "true")
+		t.Setenv("DD_TRACE_SOURCE_HOSTNAME", "")
+
+		cfg := Get()
+		require.NotNil(t, cfg)
+
+		// Empty string explicitly set should override the looked-up hostname
+		assert.Empty(t, cfg.Hostname(), "Empty DD_TRACE_SOURCE_HOSTNAME should override hostname lookup")
+		assert.True(t, cfg.ReportHostname(), "ReportHostname should be true when DD_TRACE_SOURCE_HOSTNAME is explicitly set")
+	})
+}