fix(demo): hotrod was broken

In the demo, the hotrod app was emitting trace events without
attributes, including name. It seems that is related to this PR:
jaegertracing/jaeger#4187

For now, the easy fix is to rollback hotrod to Jaeger version 1.41.

demo/Dockerfile.hotrod

@@ -3,7 +3,7 @@ FROM golang:1.20-alpine3.16 AS builder
 RUN apk --update --no-cache add git
 ENV CGO_ENABLED 0
 
-RUN git clone --branch v1.43.0 --depth 1 https://github.com/jaegertracing/jaeger
+RUN git clone --branch v1.41.0 --depth 1 https://github.com/jaegertracing/jaeger
 WORKDIR /go/jaeger
 COPY demo/hotrod.patch .
 RUN git apply hotrod.patch

demo/docker-compose.yml

@@ -49,8 +49,8 @@ services:
     depends_on:
     - otelcol-influxdb
     environment:
-      OTEL_EXPORTER_OTLP_ENDPOINT: http://otelcol-influxdb:4318
-    command: [ "all", "--otel-exporter=otlp"]
+      JAEGER_AGENT_HOST: otelcol-influxdb
+      JAEGER_AGENT_PORT: 6831
 
   otelcol-influxdb:
     build:

demo/hotrod.patch

@@ -1,18 +1,13 @@
 --- a/examples/hotrod/cmd/root.go
 +++ b/examples/hotrod/cmd/root.go
-@@ -98,12 +98,9 @@ func onInitialize() {
+@@ -81,7 +81,9 @@ func init() {
+ 	RootCmd.PersistentFlags().StringVarP(&jaegerUI, "jaeger-ui", "j", "http://localhost:16686", "Address of Jaeger UI to create [find trace] links")
+
+ 	rand.Seed(int64(time.Now().Nanosecond()))
+-	logger, _ = zap.NewDevelopment(
++	loggerConfig := zap.NewProductionConfig()
++	loggerConfig.Level.SetLevel(zapcore.FatalLevel)
++	logger, _ = loggerConfig.Build(
  		zap.AddStacktrace(zapcore.FatalLevel),
  		zap.AddCallerSkip(1),
- 	}
--	if !verbose {
--		zapOptions = append(zapOptions,
--			zap.IncreaseLevel(zap.LevelEnablerFunc(func(l zapcore.Level) bool { return l != zapcore.DebugLevel })),
--		)
--	}
--	logger, _ = zap.NewDevelopment(zapOptions...)
-+	loggerConfig := zap.NewProductionConfig()
-+	loggerConfig.Level.SetLevel(zapcore.ErrorLevel)
-+	logger, _ = loggerConfig.Build(zapOptions...)
-
- 	jaegerclientenv2otel.MapJaegerToOtelEnvVars(logger)
-
+ 	)

demo/otelcol-config.yml

@@ -1,4 +1,9 @@
 receivers:
+  jaeger:
+    protocols:
+      thrift_compact:
+      thrift_http:
+
   otlp:
     protocols:
       grpc:
@@ -35,7 +40,7 @@ service:
 
   pipelines:
     traces:
-      receivers: [otlp]
+      receivers: [otlp, jaeger]
       processors: [spanmetrics]
       exporters: [influxdb]