@govuk-one-login/data-npm

• @govuk-one-login/data-npm
  • Install
  • Usage
    • Extending with service-specific log events
  • Generic log events
  • Development
    • Code formatting
  • Publishing
    • 1. Create a changeset
      • Single change
      • Multiple changes in one release
      • Changing the version type
    • 2. Version the package
    • 3. Commit and open a pull request
    • 4. What happens on merge to main

Standardised logger for GOV.UK One Login data pod Lambda functions, built on AWS Lambda Powertools and published to npm.

Install

npm install @govuk-one-login/data-npm

Usage

import { DataLogger, LogEvents } from "@govuk-one-login/data-npm";

const logger = new DataLogger("my-service", "my-namespace");

// In your Lambda handler:
logger.initialise(context);
logger.infoWithMetrics("Started", LogEvents.StartedProcessing);

Extending with service-specific log events

import { DataLogger } from "@govuk-one-login/data-npm";

enum MyLogEvents {
  SomethingHappened = "Something Happened",
}

const logger = new DataLogger<MyLogEvents>("my-service");
logger.infoWithMetrics("msg", MyLogEvents.SomethingHappened);

Generic log events

| Event | Value | | --------------------------------- | -------------------------- | | LogEvents.StartedProcessing | 'Started Processing' | | LogEvents.SuccessfullyProcessed | 'Successfully Processed' | | LogEvents.ErrorProcessing | 'Error Processing' |

Development

npm install
npm run build
npm test

Code formatting

npm run format

Publishing

This package uses Changesets for version management and publishing. Publishing, git tags, and GitHub Releases are automated by the release workflow on merge to main.

1. Create a changeset

After making your code changes, create a changeset to describe what changed:

npx changeset

Follow the prompts to select the bump type (patch, minor, or major) — this controls the version number. Then write a description — this becomes the changelog entry.

Alternatively, create the changeset file manually at .changeset/<any-name>.md:

Single change

---
"@govuk-one-login/data-npm": minor
---

Add support for custom metric dimensions

Multiple changes in one release

If you're making multiple changes that should ship under the same version number, list them in a single changeset. Run npx changeset once, or create the file manually:

---
"@govuk-one-login/data-npm": patch
---

- Automate release workflow with Changesets GitHub Action
- Align .npmrc auth token with setup-node
- Remove redundant registry-url from CI workflow

The frontmatter controls the version bump (patch, minor, or major). The body controls the changelog entry.

Changing the version type

If you need to change the bump type after creating the changeset, edit the frontmatter in the .changeset/*.md file before running changeset version.

2. Version the package

Run the version command to consume the changeset, bump package.json, and update CHANGELOG.md:

npx changeset version

3. Commit and open a pull request

Commit your code changes together with the version bump and changelog update.

git add .
git commit -m "feat: add custom metric dimensions"
git push

4. What happens on merge to main

Once your PR is merged to main, the release workflow automatically:

1. Publishes the package to npm
2. Creates a git tag (v0.0.8, etc.)
3. Creates a GitHub Release

If the version is already published (e.g. a non-release PR), the workflow skips gracefully.