Netlify CLI and OpenTelemetry
Netlify is a popular continuous integration, continuous deployment, and hosting platform for static sites and serverless functions. OpenTelemetry is a collection of tools, APIs, and SDKs that can be used to generate, collect, and export telemetry data. In this documentation, we will explore how to use OpenTelemetry with Netlify CLI.
Prerequisites
Before we begin, make sure you have the following prerequisites in place:
- A Netlify account
- Node.js installed on your machine
- OpenTelemetry SDK for JavaScript installed
Installing OpenTelemetry SDK for JavaScript
To use OpenTelemetry with Netlify CLI, you need to install the OpenTelemetry SDK for JavaScript. You can do this by running the following command in your terminal:
npm install @opentelemetry/sdk
Configuring OpenTelemetry with Netlify CLI
To configure OpenTelemetry with Netlify CLI, you need to create a tracing.js file in the root directory of your project. This file will contain the configuration for OpenTelemetry. Here’s an example of what the tracing.js file might look like:
const { NodeTracerProvider } = require('@opentelemetry/sdk-node');
const { SimpleSpanProcessor, ConsoleSpanExporter } = require('@opentelemetry/sdk-trace-base');
const provider = new NodeTracerProvider();
provider.registerSpanProcessor(
new SimpleSpanProcessor(new ConsoleSpanExporter())
);
provider.register();
This configuration sets up a NodeTracerProvider and registers a SimpleSpanProcessor with a ConsoleSpanExporter. This will cause OpenTelemetry to output tracing information to the console.
Instrumenting your application with OpenTelemetry
To instrument your application with OpenTelemetry, you need to import the @opentelemetry/instrumentation-node package and call its instrumentFunction method. Here’s an example of how you might instrument a Node.js Express application:
const express = require('express');
const { instrumentFunction } = require('@opentelemetry/instrumentation-node');
const app = express();
app.get('/', (req, res) => {
res.send('Hello World!');
});
// Instrument the Express application
instrumentFunction(app);
app.listen(3000, () => {
console.log('Example app listening on port 3000!');
});
This example instruments the Express application by calling instrumentFunction with the app object.
Building a Netlify CLI plugin with OpenTelemetry
To build a Netlify CLI plugin with OpenTelemetry, you need to create a new Node.js project and install the necessary dependencies. Here’s an example of what the package.json file for the project might look like:
{
"name": "my-netlify-cli-plugin",
"version": "1.0.0",
"description": "A Netlify CLI plugin that uses OpenTelemetry for tracing",
"main": "index.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1"
},
"dependencies": {
"@opentelemetry/api": "^1.1.0",
"@opentelemetry/exporter-console": "^1.1.0",
"@opentelemetry/instrumentation-node": "^0.29.2",
"netlify-cli": "^1.1.0"
}
}
This package.json file includes the necessary dependencies for OpenTelemetry and Netlify CLI.
Next, you need to create the index.js file for your plugin. This file will contain the code for your plugin, including the configuration for OpenTelemetry and the implementation of the Netlify CLI command. Here’s an example of what the index.js file might look like:
const { NodeTracerProvider } = require('@opentelemetry/sdk-node');
const { SimpleSpanProcessor, ConsoleSpanExporter } = require('@opentelemetry/sdk-trace-base');
const { Command } = require('netlify-cli');
const provider = new NodeTracerProvider();
provider.registerSpanProcessor(
new SimpleSpanProcessor(new ConsoleSpanExporter())
);
provider.register();
class MyCommand extends Command {
constructor(name, args) {
super(name, args);
}
async run() {
this.log('Running my command...');
// Create a new span for this command
const span = this.tracer.startSpan('my-command');
try {
// Perform the command logic here
// ...
// Set the status and end the span
span.setStatus({ code: 0, message: 'Success' });
span.end();
} finally {
// Always end the span, even if an error occurs
span.end();
}
}
get tracer() {
return provider.getTracer('my-command-tracer');
}
}
module.exports = MyCommand;
This example creates a new MyCommand class that extends the Command class from Netlify CLI. It also sets up OpenTelemetry with a NodeTracerProvider and a ConsoleSpanExporter. The run method of the MyCommand class creates a new span for the command and sets its status when the command completes.
Finally, you need to export the MyCommand class from the index.js file so that it can be used as a Netlify CLI command. Here’s an example of what the last few lines of the index.js file might look like:
module.exports = MyCommand;
With this setup, you can now use your Netlify CLI plugin with OpenTelemetry by running the following command in your terminal:
netlify plugin install ./path/to/your/plugin
Replace ./path/to/your/plugin with the path to your plugin directory. Once the plugin is installed, you can use it as a regular Netlify CLI command.
Conclusion
In this documentation, we explored how to use OpenTelemetry with Netlify CLI to generate, collect, and export telemetry data for your Netlify-deployed applications. We covered the prerequisites for using OpenTelemetry with Netlify CLI, how to configure OpenTelemetry, how to instrument your application with OpenTelemetry, and how to build a Netlify CLI plugin with OpenTelemetry. By following the steps outlined in this documentation, you’ll be able to gain valuable insights into the performance and behavior of your Netlify-deployed applications.
