Jaeger back end isn't recieving any data (using Jager Node.js client)

Question

I'm trying to get a little example of Jaeger working using Node.js, but I can't get the Jaeger UI to display any data or show anything.

I have read this question: uber/jaeger-client-node: backend wont receive data but this hasn't helped in my case.

I'm running the Jaeger back end in a docker container using:

docker run -d -e COLLECTOR_ZIPKIN_HTTP_PORT=9411 -p5775:5775/udp -p6831:6831/udp -p6832:6832/udp -p5778:5778 -p16686:16686 -p14268:14268 -p9411:9411 jaegertracing/all-in-one:latest

The code for my example is:

var initTracer = require('jaeger-client').initTracer;

// See schema https://github.com/jaegertracing/jaeger-client-node/blob/master/src/configuration.js#L37
var config = {
  'serviceName': 'my-awesome-service'
};
var options = {
  'tags': {
    'my-awesome-service.version': '1.1.2'
  }
  //'metrics': metrics,
  //'logger': logger
};
var tracer = initTracer(config, options);

const express = require('express');
const app = express();

// Handle a GET request on the root path
app.get('/', (req, res) => {
    const span = tracer.startSpan('http_request');
    res.send('Hello Jaeger');
    span.log({'event': 'request_end'});
    span.finish();
});

// Set up server
const server = app.listen(8000, () => {
    let host = server.address().address;
    let port = server.address().port;

    console.log('Service_1 listening at http://%s:%s', host, port);
});

Any help as to what I am doing wrong would be much appreciated!

Answer 1

You need to add some more properties to your config options. For reporter deployed on localhost and local sampler strategy :

var config = {
  'serviceName': 'my-awesome-service',
  'reporter': {
    'logSpans': true,
    'agentHost': 'localhost',
    'agentPort': 6832
  },
  'sampler': {
    'type': 'probabilistic',
    'param': 1.0
  }
};

Replace localhost by server or route name to target another host for Jeager runtime.

Answer 2

I spent almost two days figuring this out. It does not work with "'agentHost': 'localhost'" when you are running your containers via separate docker-compose commands. I had one nodeJS microservice and one container for jaeger and the following combination worked for me.

1. First step is to create a network that will be used to launch all your services as well as the Jaeger container.

   docker network create -d bridge my_network (replace my_network with your desired network name)
   

2. Create a Jaeger container that runs in the same network

   docker run --network my_network --name jaeger -d -e COLLECTOR_ZIPKIN_HTTP_PORT=9411 -p5775:5775/udp -p6831:6831/udp -p6832:6832/udp -p5778:5778 -p16686:16686 -p14268:14268 -p9411:9411 jaegertracing/all-in-one:latest
   

3. Create a folder and create app.js file and paste the following code to create a nodeJS microservice.

    const express = require("express");
    var http = require("http");
    const app = express();
    const port = 8082;
    const serviceName = process.env.SERVICE_NAME || "service-a";
   
    // Initialize the Tracer
    const tracer = initTracer(serviceName);
    const opentracing = require("opentracing");
    opentracing.initGlobalTracer(tracer);
   
   // Instrument every incoming request
   app.use(tracingMiddleWare);
   
   // Let's capture http error span
   app.get("/error", (req, res) => {
    res.status(500).send("some error (ノ ゜Д゜)ノ ︵ ┻━┻");
   });
   
   app.get("/sayHello/:name", (req, res) => {
    const span = tracer.startSpan("say-hello", , { childOf: req.span });
    // Parse the handler input
    const name = req.params.name
   
    // show how to do a log in the span
    span.log({ event: 'name', message: `this is a log message for name ${name}` })
    // show how to set a baggage item for context propagation (be careful is expensive)
    span.setBaggageItem('my-baggage', name)
    span.finish()
    res.send(response);
   });
   
   app.disable("etag");
    app.listen(port, () =>
      console.log(`Service ${serviceName} listening on port ${port}!`)
   );
   
    function initTracer(serviceName) {
     var initTracer1 = require("jaeger-client").initTracer;
   
     // See schema https://github.com/jaegertracing/jaeger-client-node/blob/master/src/configuration.js#L37
     var config = {
       serviceName: serviceName,
       reporter: {
        logSpans: true,
        agentHost: "jaeger",
        agentPort: 6832,
       },
       sampler: {
        type: "probabilistic",
        param: 1.0,
       },
      };
      var options = {
       logger: {
        info: function logInfo(msg) {
         console.log("INFO ", msg);
        },
        error: function logError(msg) {
         console.log("ERROR", msg);
        },
       },
      };
   
     return initTracer1(config, options);
    }
   
    function tracingMiddleWare(req, res, next) {
     const tracer = opentracing.globalTracer();
     const wireCtx = tracer.extract(opentracing.FORMAT_HTTP_HEADERS, req.headers);
     // Creating our span with context from incoming request
     const span = tracer.startSpan(req.path, { childOf: wireCtx });
     // Use the log api to capture a log
     span.log({ event: "request_received" });
   
     // Use the setTag api to capture standard span tags for http traces
     span.setTag(opentracing.Tags.HTTP_METHOD, req.method);
     span.setTag(
      opentracing.Tags.SPAN_KIND,
      opentracing.Tags.SPAN_KIND_RPC_SERVER
     );
     span.setTag(opentracing.Tags.HTTP_URL, req.path);
   
     // include trace ID in headers so that we can debug slow requests we see in
     // the browser by looking up the trace ID found in response headers
     const responseHeaders = {};
     tracer.inject(span, opentracing.FORMAT_HTTP_HEADERS, responseHeaders);
     res.set(responseHeaders);
   
     // add the span to the request object for any other handler to use the span
     Object.assign(req, { span });
   
     // finalize the span when the response is completed
     const finishSpan = () => {
      if (res.statusCode >= 500) {
      // Force the span to be collected for http errors
      span.setTag(opentracing.Tags.SAMPLING_PRIORITY, 1);
      // If error then set the span to error
      span.setTag(opentracing.Tags.ERROR, true);
   
      // Response should have meaning info to futher troubleshooting
      span.log({ event: "error", message: res.statusMessage });
     }
     // Capture the status code
     span.setTag(opentracing.Tags.HTTP_STATUS_CODE, res.statusCode);
     span.log({ event: "request_end" });
     span.finish();
    };
    res.on("finish", finishSpan);
    next();
   }
   

I have taken the reference of the above code from https://github.com/ibm-cloud-architecture/learning-distributed-tracing-101 repo from "lab-jaeger-nodejs/solution/service-a/app.js" folder.

5. Create "package.json" in the same nodeJS folder where the above app.js file is created with the following code

    {
     "name": "service",
     "version": "0.0.0",
     "scripts": {
      "start": "node app.js",
      "debug": "npm start",
     },
     "dependencies": {
      "express": "^4.17.1",
      "jaeger-client": "^3.15.0"
     },
     "devDependencies": {
      "standard": "^14.0.2"
    }
   }
   

6. Create a "DOCKERfile" inside the same nodeJS folder with following code

    FROM node:12.9.1
   
    # Create app directory
    WORKDIR /usr/src/app
   
    COPY package.json .
   
    RUN npm install
    # If you are building your code for production
    # RUN npm ci --only=production
   
    # Bundle app source
    COPY . .
   
    EXPOSE 8082
    CMD [ "npm", "start" ]
   

7. Create "docker-compose.yaml" file within the same folder.

    version: "3.7"
     services:
      service-a:
       build: ./service-a
       ports:
        - "8082:8082"
       networks:
        - my_network
     networks:
      my_network:
       external: true
       name: my_network
   

8. Now run the following commands from terminal. This will run the nodeJS applicatin in the docker container

      docker-compose build
      docker-compose up
   

9. Now run the http://localhost:8082/sayHello/John. You will see the response. Then open http://localhost:16686/ and you will be able to see the Jaeger UI with search. Search for "service-a" and you will be able to find the traces.