Adding New Components

The primary purpose of Ocelot is to simplify the addition of custom components to the OpenTelemetry Collector for Lambda. This guide outlines the process.

The Wrapper Approach

Instead of placing the full source code of a component into this repository, Ocelot uses a “wrapper” approach. You create a simple Go file that acts as a bridge to the actual component’s source code, which is fetched as a Go module dependency.

This keeps the Ocelot repository lean and focused only on the integration logic.

Steps to Add a Component

Let’s assume you want to add a new exporter called myexporter.

1. Create the Component Directory

Create a new directory for your component under the appropriate type in components/collector/lambdacomponents/.

mkdir -p components/collector/lambdacomponents/exporter/myexporter

2. Create the Wrapper Go File

Inside the new directory, create a Go file (e.g., myexporter.go). This file will contain:

1. A build tag that includes the proper conditions for inclusion.
2. An init() function that registers the factory.
3. An import statement that references the actual component package.

Here is the template:

//go:build lambdacomponents.custom && (lambdacomponents.all || lambdacomponents.exporter.all || lambdacomponents.exporter.myexporter)

package exporter

import (
	"github.com/actual-repo/my-exporter-component" // The real component package
	"go.opentelemetry.io/collector/exporter"
)

func init() {
	Factories = append(Factories, func(extensionId string) exporter.Factory {
		return myexporter.NewFactory() // Call the actual component's factory
	})
}

3. Add the Go Dependency

Add the Go module dependency to the config/component_dependencies.yaml file. This maps your build tag to the required Go module:

dependencies:
  # ... existing dependencies
  lambdacomponents.exporter.myexporter:
    - github.com/actual-repo/my-exporter-component
    # Or with a specific version:
    # - github.com/actual-repo/my-exporter-component@v1.2.3

The build script will automatically run go get and go tidy for these dependencies when your component is included in a build.

4. Define a Distribution

Add your new component’s build tag to a distribution in config/distributions.yaml. You can add it to an existing distribution or create a new one.

distributions:
  # ...
  minimal-my-exporter:
    description: "Minimal + My Exporter"
    base: minimal
    build-tags:
      - "lambdacomponents.exporter.myexporter"

5. Build and Test

You can now build a layer with your new component!

uv run tools/ocelot.py --distribution minimal-my-exporter