NestJS

Instrument your NestJS application using Aspecto

Auto Instrument

Nest applications are commonly started in one of 2 ways:

• Nest cli (nest start)

• Directly with the node executable (for example: node dist/main)

It is recommended to use "Auto Instrument" technique with node's "preload" command line option, to ensure instrumentation is initialized before Nest framework.

Using Nest Cli

To instrument your Nest application when started with Nest cli, add the "-e" ("--exec") option to nest start like this:

nest start -e 'node -r @aspecto/opentelemetry/auto-instrument'

This should be added everywhere nest start is invoked (package.json, scripts, terminal, etc).

Using Node Executable

To instrument you Nest application when started with node executable, add the "-r" ("--require") to node execution like this:

node -r '@aspecto/opentelemetry/auto-instrument' dist/main

Configuration

When instrumenting an application with "Auto Instrument", configuration is supplied via environment variables or aspecto.json file.

ASPECTO_AUTH must be provided. Other configuration options are optional.

.env File

This part is relevant if you are using @nestjs/config package to load environment variables from .env file (or if you are loading the file yourself).

If you store Aspecto's SDK config options in .env file, it needs to be preloaded before @aspecto/opentelemetry, e.g.

nest start -e 'node -r dotenv/config -r @aspecto/opentelemetry/auto-instrument'
// or
node -r dotenv/config -r '@aspecto/opentelemetry/auto-instrument' dist/main