tracing tweaks

cart/server.js

@@ -1,16 +1,17 @@
 const instana = require('instana-nodejs-sensor');
-const redis = require('redis');
-const request = require('request');
-const bodyParser = require('body-parser');
-const express = require('express');
-
 // init tracing
+// MUST be done before loading anything else!
 instana({
     tracing: {
         enabled: true
     }
 });
 
+const redis = require('redis');
+const request = require('request');
+const bodyParser = require('body-parser');
+const express = require('express');
+
 var redisConnected = false;
 
 const app = express();
@@ -66,6 +67,24 @@ app.delete('/cart/:id', (req, res) => {
     });
 });
 
+// rename cart i.e. at login
+app.get('/rename/:from/:to', (req, res) => {
+    redisClient.get(req.params.from, (err, data) => {
+        if(err) {
+            console.log('ERROR', err);
+            res.status(500).send(err);
+        } else {
+            if(data == null) {
+                res.status(404).send('cart not found');
+            } else {
+                var cart = JSON.parse(data);
+                saveCart(req.params.to, cart);
+                res.json(cart);
+            }
+        }
+    });
+});
+
 // update/create cart
 app.get('/add/:id/:sku/:qty', (req, res) => {
     // check quantity

catalogue/server.js

@@ -1,16 +1,17 @@
 const instana = require('instana-nodejs-sensor');
-const mongoClient = require('mongodb').MongoClient;
-const mongoObjectID = require('mongodb').ObjectID;
-const bodyParser = require('body-parser');
-const express = require('express');
-
 // init tracing
+// MUST be done before loading anything else!
 instana({
     tracing: {
         enabled: true
     }
 });
 
+const mongoClient = require('mongodb').MongoClient;
+const mongoObjectID = require('mongodb').ObjectID;
+const bodyParser = require('body-parser');
+const express = require('express');
+
 // MongoDB
 var db;
 var collection;

dispatch/src/main.go

@@ -8,7 +8,7 @@ import (
     "github.com/streadway/amqp"
     "github.com/instana/golang-sensor"
     ot "github.com/opentracing/opentracing-go"
-    // ext "github.com/opentracing/opentracing-go/ext"
+    ext "github.com/opentracing/opentracing-go/ext"
 )
 
 const (
@@ -77,6 +77,33 @@ func failOnError(err error, msg string) {
     }
 }
 
+func createSpan(headers map[string]interface{}) {
+    // headers is map[string]interface{}
+    // carrier is map[string]string
+    carrier := make(ot.TextMapCarrier)
+    // convert by copying k, v
+    for k, v := range headers {
+        carrier[k] = v.(string)
+    }
+
+    // opentracing
+    var span ot.Span
+    tracer := ot.GlobalTracer()
+    spanContext, err := tracer.Extract(ot.HTTPHeaders, carrier)
+    if err == nil {
+        log.Println("Creating span")
+        // create span
+        span = tracer.StartSpan("dispatch", ot.ChildOf(spanContext), ext.SpanKindConsumer)
+        ext.MessageBusDestination.Set(span, "orders")
+        ext.Component.Set(span, "dispatch")
+        defer span.Finish()
+        time.Sleep(42 * time.Millisecond)
+    } else {
+        log.Println("Failed to get span context")
+        log.Println(err)
+    }
+}
+
 
 func main() {
     // Instana tracing
@@ -106,6 +133,8 @@ func main() {
 
             for d := range msgs {
                 log.Printf("Order %s\n", d.Body)
+                log.Printf("Headers %v\n", d.Headers)
+                go createSpan(d.Headers)
             }
         }
     }()

payment/payment.py

@@ -4,6 +4,8 @@ import time
 import logging
 import uuid
 import requests
+import opentracing as ot
+import opentracing.ext.tags as tags
 from flask import Flask
 from flask import request
 from flask import jsonify
@@ -36,7 +38,26 @@ def pay(id):
 
 def queueOrder(order):
     app.logger.info('queue order')
-    publisher.publish(order)
+    # RabbitMQ is not currently traced automatically
+    # opentracing tracer is automatically set to Instana tracer
+    # start a span
+    context = ot.tracer.current_context()
+    span = ot.tracer.start_span(operation_name='queue-order',
+            child_of=ot.tracer.current_context(),
+            tags={
+                tags.SPAN_KIND: 'producer',
+                tags.COMPONENT: 'payment',
+                'message_bus.destination': 'orders'
+                }
+            )
+
+    headers = {}
+    ot.tracer.inject(span.context, ot.Format.HTTP_HEADERS, headers)
+    app.logger.info('msg headers {}'.format(headers))
+    
+    publisher.publish(order, headers)
+
+    span.finish()
 
 # RabbitMQ
 publisher = Publisher(app.logger)

payment/rabbitmq.py

@@ -24,22 +24,23 @@ class Publisher:
             self._channel.exchange_declare(exchange=self.EXCHANGE, exchange_type=self.TYPE, durable=True)
             self._logger.info('connected to broker')
 
-    def _publish(self, msg):
+    def _publish(self, msg, headers):
         self._channel.basic_publish(exchange=self.EXCHANGE,
                                     routing_key=self.ROUTING_KEY,
+                                    properties=pika.BasicProperties(headers=headers),
                                     body=json.dumps(msg).encode())
         self._logger.info('message sent')
 
     #Publish msg, reconnecting if necessary.
-    def publish(self, msg):
+    def publish(self, msg, headers):
         if self._channel is None:
             self._connect()
         try:
-            self._publish(msg)
+            self._publish(msg, headers)
         except pika.exceptions.ConnectionClosed:
             self._logger.info('reconnecting to queue')
             self._connect()
-            self._publish(msg)
+            self._publish(msg, headers)
 
     def close(self):
         if self._conn and self._conn.is_open:

user/server.js

@@ -1,17 +1,18 @@
 const instana = require('instana-nodejs-sensor');
-const mongoClient = require('mongodb').MongoClient;
-const mongoObjectID = require('mongodb').ObjectID;
-const redis = require('redis');
-const bodyParser = require('body-parser');
-const express = require('express');
-
 // init tracing
+// MUST be done before loading anything else!
 instana({
     tracing: {
         enabled: true
     }
 });
 
+const mongoClient = require('mongodb').MongoClient;
+const mongoObjectID = require('mongodb').ObjectID;
+const redis = require('redis');
+const bodyParser = require('body-parser');
+const express = require('express');
+
 // MongoDB
 var db;
 var collection;
@@ -39,11 +40,14 @@ app.get('/health', (req, res) => {
 // use REDIS INCR to track anonymous users
 app.get('/uniqueid', (req, res) => {
     // get number from Redis
-    redisClient.incr('user', (err, r) => {
+    redisClient.incr('anonymous-counter', (err, r) => {
         if(!err) {
             res.json({
                 uuid: 'anonymous-' + r
             });
+        } else {
+            console.log('ERROR', err);
+            res.status(500).send(err);
         }
     });
 });