Sentry OpenTelemetry/Node Sample Application

This repository contains a set of Node.js/Express services that provide a simple multi-tier application that lets you vote for using spaces versus tabs in code.

• voting-frontend renders the website using data fetched from voting-service-gateway.
• voting-service-gateway randomly toggles between voting-service-green and voting-service-green and passes the request through to the respective service.
• voting-service-green provides the access layer to MongoDB where the data is stored.
• voting-service-blue represents a faulty version and returns an error.

Installation

• This sample expects MongoDB to be running on localhost:27017 - please install the community edition following the instructions for your platform.
• After downloading/cloning this repository open your console, change into the root of the repository and run install.sh to install all dependencies. This can take a while.
• While still in the root directory, run npx pm2 startOrRestart ecosystem.config.js. Answer "yes" if you are prompted if pm2 should be downloaded.
• (To stop all services, run npx pm2 stop ecosystem.config.js.)

Setting up Sentry

1. Copy .env-sample and rename it to .env.
2. In Sentry, create the following projects and edit .env to set the respective DSN:

• browser (JS)
• frontend (Express)
• gateway (Express)
• service-green (Express)
• service-blue (Express)

3. Restart all services by running npx pm2 startOrRestart ecosystem.config.js.

Using the Sample Application

The frontend at localhost:8080. Use the buttons to cast your vote. Every time a ☠️ is shown instead of the tally, you hit the faulty service-blue.

Troubleshooting

If you can't access the frontend, or voting doesn't work, run pm2 status and look for a service with status error. Do get the logs for a service, run pm2 logs servicename.

Known Issues

• Currently some transactions may show up as << unparameterized >>.
• Currently the frontend traces don't connected to the backend traces.