@aws-cdk/cloudformation-diff

What is @aws-cdk/cloudformation-diff?

@aws-cdk/cloudformation-diff is a package that provides tools to compare AWS CloudFormation templates. It helps in identifying the differences between two CloudFormation templates, which is useful for understanding changes before applying them.

What are @aws-cdk/cloudformation-diff's main functionalities?

Template Diffing

This feature allows you to compare two CloudFormation templates and identify the differences. The `diffTemplate` function takes two templates as input and returns the differences.

const { diffTemplate } = require('@aws-cdk/cloudformation-diff');
const templateA = require('./templateA.json');
const templateB = require('./templateB.json');
const differences = diffTemplate(templateA, templateB);
console.log(differences);

Change Detection

This feature helps in detecting specific changes between two templates. By iterating over the differences, you can log or handle each change individually.

const { diffTemplate } = require('@aws-cdk/cloudformation-diff');
const templateA = require('./templateA.json');
const templateB = require('./templateB.json');
const differences = diffTemplate(templateA, templateB);
differences.forEach(diff => {
  console.log(`Change detected: ${diff}`);
});

Resource Comparison

This feature focuses on comparing resources within the templates. It allows you to identify changes specific to resources, which is useful for understanding the impact on infrastructure.

const { diffTemplate } = require('@aws-cdk/cloudformation-diff');
const templateA = require('./templateA.json');
const templateB = require('./templateB.json');
const differences = diffTemplate(templateA, templateB);
differences.resources.forEach(resourceDiff => {
  console.log(`Resource change detected: ${resourceDiff}`);
});

Other packages similar to @aws-cdk/cloudformation-diff

cfn-diff

cfn-diff is a package that provides similar functionality for comparing AWS CloudFormation templates. It offers tools to detect changes and differences between templates, similar to @aws-cdk/cloudformation-diff. However, it may not be as tightly integrated with the AWS CDK ecosystem.

README

Utilities to diff AWS CDK stacks against CloudFormation templates

This module is part of the AWS Cloud Development Kit project.