instrumented

Instrumented JavaScript Demo Fibonacci App

This is a simple web application that calculates and visualizes Fibonacci numbers. The app is built using Node.js, Express, and Chart.js.

Requires:

• Node.js 14+
• A New Relic account

Features

• Calculate the nth Fibonacci number (1 <= n <= 90)
• Display the calculated Fibonacci number
• Visualize the Fibonacci sequence up to the nth number using a line chart

Architecture

The application is divided into two main parts:

1. Backend: A Node.js/Express server that exposes a REST API to calculate Fibonacci numbers.
2. Frontend: A browser-based single-page application that utilizes the REST API to fetch Fibonacci numbers and visualize the sequence using Chart.js.

The frontend code is organized in the following manner:

• index.html: The HTML structure of the single-page application.
• app.js: The JavaScript code responsible for handling user input, interacting with the backend REST API, and updating the chart.
• styles.css: The CSS file containing the styles for the frontend.

The server-side code is organized in the following manner:

• server.js: The main entry point of the server that sets up the Express app and listens for incoming connections.
• routes.js: A separate module containing the Express routes for handling the Fibonacci REST API.

Installation

1. Clone the repository or download the source code:

git clone https://github.com/newrelic/newrelic-opentelemetry-examples.git

2. Navigate to the project folder:

cd getting-started-guides/javascript/instrumented

3. Install the required dependencies:

npm install

Usage

1. Start the app:

npm start

The above command will use parcel to build the frontend and start the server.

2. Open your browser and navigate to http://localhost:8080 to access the app.

Open Telemetry Auto Instrumentation for Web

To enable OpenTelemetry auto instrumentation for the web, the following modules have been installed:

npm install @opentelemetry/auto-instrumentations-web \
  @opentelemetry/sdk-trace-web \
  @opentelemetry/sdk-trace-base \
  @opentelemetry/instrumentation \
  @opentelemetry/context-zone \
  @opentelemetry/exporter-trace-otlp-proto \
  @opentelemetry/resources \
  @opentelemetry/semantic-conventions

Refer to the auto-otel-web.js file for the implementation details.

Open Telemetry manual instrumentation for Web

To enable OpenTelemetry custom/manual instrumentation for the web, the following modules have been installed:

npm install @opentelemetry/api \
  @opentelemetry/sdk-trace-web \
  @opentelemetry/sdk-trace-base \
  @opentelemetry/instrumentation \
  @opentelemetry/context-zone \
  @opentelemetry/instrumentation-document-load \
  @opentelemetry/instrumentation-user-interaction \
  @opentelemetry/instrumentation-fetch \
  @opentelemetry/exporter-trace-otlp-proto \
  @opentelemetry/resources \
  @opentelemetry/semantic-conventions

Refer to the manual-otel-web.js file for the implementation details.

Open Telemetry Auto Instrumentation for Backend (Node.js)

To enable OpenTelemetry auto instrumentation for the backend, the following modules have been installed:

npm install @opentelemetry/auto-instrumentations-node \
  @opentelemetry/sdk-node \
  @opentelemetry/sdk-trace-node \
  @opentelemetry/sdk-metrics \
  @opentelemetry/resources \
  @opentelemetry/semantic-conventions

To be able to send traces and metrics to New Relic, exporter modules have to be installed:

npm install @opentelemetry/exporter-trace-otlp-proto \
  @opentelemetry/exporter-metrics-otlp-proto

And the New Relic Api Key has been added to the .env file:

NEW_RELIC_LICENSE_INGEST_KEY=<NEW_RELIC_LICENSE_INGEST_KEY>

Refer to the auto-otel-node.js file for the implementation details.

Notice the npm server command has been updated to include the -r option to load the auto-otel-node.js file.

// package.json
"scripts": {
    ...
    "server": "node -r ./src/auto-otel-node.js src/server.js",
    ...
  },

Open Telemetry manual instrumentation for Backend (Node.js)

To enable OpenTelemetry custom/manual instrumentation for the backend, the following modules have been installed:

npm install @opentelemetry/api \
  @opentelemetry/sdk-trace-node \
  @opentelemetry/sdk-metrics \
  @opentelemetry/instrumentation \
  @opentelemetry/resources \
  @opentelemetry/semantic-conventions

To be able to send traces and metrics to New Relic, exporter modules have to be installed:

npm install @opentelemetry/exporter-trace-otlp-proto \
  @opentelemetry/exporter-metrics-otlp-proto

And the New Relic Api Key has been added to the .env file:

NEW_RELIC_LICENSE_INGEST_KEY=<NEW_RELIC_LICENSE_INGEST_KEY>

Refer to the manual-otel-node.js file for the implementation details.

Notice the npm server command has been updated to include the -r option to load the manual-otel-node.js file.

// package.json
"scripts": {
    ...
    "server": "node -r ./src/manual-otel-node.js src/server.js",
    ...
  },

Further reading

Custom Instrumentation for the backend logic can be found in the API README.md file

License

This project is MIT licensed.