mark handler_endpoint as unsupported for spanmetrics conversion

Signed-off-by: erikbaranowski <[email protected]>

internal/converter/internal/staticconvert/internal/build/builder_traces.go

@@ -89,6 +89,15 @@ func (b *ConfigBuilder) translateSpanMetrics(otelCfg *otelcol.Config, cfg traces
 	removeExporter(otelCfg, "metrics", "prometheus")
 	delete(otelCfg.Service.Pipelines, metricsSpanmetricsID)
 
+	// If the spanmetrics configuration includes a handler_endpoint, we cannot convert it.
+	// This is intentionally after the section above which removes the custom spanmetrics processor
+	// so that the rest of the configuration can optionally be converted with the error.
+	if cfg.SpanMetrics.HandlerEndpoint != "" {
+		b.diags.Add(diag.SeverityLevelError, "Cannot convert using configuration including spanmetrics handler_endpoint. "+
+			"No equivalent exists for exposing a known /metrics endpoint. You can use metrics_instance instead to enabled conversion.")
+		return
+	}
+
 	// Add the spanmetrics connector to the otel config with the converted configuration
 	if otelCfg.Connectors == nil {
 		otelCfg.Connectors = map[otel_component.ID]otel_component.Config{}
@@ -134,7 +143,6 @@ func toSpanmetricsConnector(cfg *traces.SpanMetricsConfig) *spanmetricsconnector
 	// TODO: decide how to handle these fields
 	// cfg.SpanMetrics.ConstLabels
 	// cfg.SpanMetrics.MetricsInstance
-	// cfg.SpanMetrics.HandlerEndpoint
 
 	return smc
 }

internal/converter/internal/staticconvert/testdata/unsupported.diags

@@ -1,6 +1,7 @@
 (Error) The converter does not support handling integrations which are not being scraped: mssql.
 (Error) mapping_config is not supported in statsd_exporter integrations config
 (Error) automatic_logging for traces has no direct flow equivalent. A best effort translation can be made which only outputs to stdout and not directly to loki by bypassing errors.
+(Error) Cannot convert using configuration including spanmetrics handler_endpoint. No equivalent exists for exposing a known /metrics endpoint. You can use metrics_instance instead to enabled conversion.
 (Warning) Please review your agent command line flags and ensure they are set in your Flow mode config file where necessary.
 (Error) The converter does not support converting the provided grpc_tls_config server config: flow mode does not have a gRPC server to configure.
 (Error) The converter does not support converting the provided prefer_server_cipher_suites server config.

internal/converter/internal/staticconvert/testdata/unsupported.yaml

@@ -64,6 +64,8 @@ traces:
         - endpoint: http://localhost:1234/write
       automatic_logging:
         backend: "something else"
+      spanmetrics:
+        handler_endpoint: http://localhost:1234/write
 
 agent_management:
   host: host_name