@dotcom-reliability-kit/app-info
A utility to get application information (e.g. the system code) in a consistent way. This module is part of FT.com Reliability Kit.
Usage
Install @dotcom-reliability-kit/app-info
as a dependency:
npm install --save @dotcom-reliability-kit/app-info
Include in your code:
import appInfo from '@dotcom-reliability-kit/app-info';
const appInfo = require('@dotcom-reliability-kit/app-info');
The appInfo
object has several properties which can be used to access application information.
appInfo.commitHash
Get the commit hash that the application last deployed. This will be a string (if process.env.HEROKU_SLUG_COMMIT
, process.env.GIT_COMMIT_LONG
, or process.env.GIT_COMMIT
is defined) or null
otherwise.
For Heroku, this relies on the Dyno Metadata labs feature and will not be present in local development.
For AWS Lambda, you can use a plugin like serverless-plugin-git-variables to provide this data or set the GIT_COMMIT
environment variable during deployment.
appInfo.environment
Get the application environment, normally either development
or production
. This will be a string, trying each of the following environment variables in order and defaulting to development
:
DEPLOYMENT_ENVIRONMENT
RELEASE_ENV
ENVIRONMENT
NODE_ENV
appInfo.region
Get the region that the application is running in. This will be a string (if process.env.REGION
or process.env.AWS_REGION
is defined) or null
otherwise.
appInfo.releaseDate
Get the application Heroku release date. This will be a string (if process.env.HEROKU_RELEASE_CREATED_AT
is defined) or null
otherwise.
For Heroku, this relies on the Dyno Metadata labs feature and will not be present in local development.
appInfo.releaseVersion
Get the application Heroku release version. This will be a string (if process.env.HEROKU_RELEASE_VERSION
or process.env.AWS_LAMBDA_FUNCTION_VERSION
is defined) or null
otherwise.
For Heroku, this relies on the Dyno Metadata labs feature and will not be present in local development.
appInfo.systemCode
Get the application's Biz Ops system code. This will be a string (if process.env.SYSTEM_CODE
is defined), if not then it will be read from the name
property of $CWD/package.json
, if neither of these exist then it will be set to null
.
If the system code is read from the application's package.json
file then it will be stripped of any "ft-"
prefix – this is a legacy name and our app system codes do not begin with it.
appInfo.processType
Get the type of the running process, which is the name for the current process within an application.
For AWS Lambda, this is the name of the function, read from process.env.AWS_LAMBDA_FUNCTION_NAME
.
For Heroku, this is derived from the first part of process.env.DYNO
, which is set to by Heroku, e.g. a dyno called web.1
will have processType
set to web
. The process types in an application are defined by the application's Procfile
.
If neither process.env.AWS_LAMBDA_FUNCTION_NAME
or process.env.DYNO
are set, this property will be null
appInfo.cloudProvider
Get the type of cloud provider which is set to either Heroku or AWS depending on where we think the system is hosted.
This is derived from some environment variables which we have high confidence are defined by only Heroku or AWS/Lambda
appInfo.herokuAppId
Get the process.env.HEROKU_APP_ID
which is the unique identifier for the application.e.g "9daa2797-e49b-4624-932f-ec3f9688e3da"
This is derived from the dyno metadata
appInfo.herokuDynoId
Get the process.env.HEROKU_DYNO_ID
which is the dyno identifier
This is derived from the dyno metadata
appInfo.instanceId
Get the unique identifier for the instance that's running the application. This will be a different UUID for each running process, including cluster workers.
appInfo.semanticConventions
This object contains aliases for the main appInfo
properties that correspond to OpenTelemetry's Semantic Conventions. We use the following mapping:
appInfo.semanticConventions.cloud.provider
aliases appInfo.cloudProvider
appInfo.semanticConventions.cloud.region
aliases appInfo.region
appInfo.semanticConventions.deployment.environment
aliases appInfo.environment
appInfo.semanticConventions.service.name
aliases appInfo.systemCode
appInfo.semanticConventions.service.version
aliases appInfo.releaseVersion
appInfo.semanticConventions.service.instance.id
aliases appInfo.instanceId
[!WARNING]
While all other properties default to null
if they can't be calculated, the semantic conventions properties default to undefined
. This is to ensure better compatibility with OpenTelemetry SDKs.
Migrating
Consult the Migration Guide if you're trying to migrate to a later major version of this package.
Contributing
See the central contributing guide for Reliability Kit.
License
Licensed under the MIT license.
Copyright © 2022, The Financial Times Ltd.