@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.

Changelog

0.21.0 (2018-12-20)

Bug Fixes

• aws-cloudformation: change the type of Role in CodePipeline Actions to IRole. (#1364) (3d07e48), closes #1361
• codebuild: Rename includeBuildID property of S3BucketBuildArtifacts (#1354) (84eb7ad), closes #1347
• toolkit: scrutiny dialog should fail with no tty (#1382) (478a714), closes #1380

Features

• aws-codebuild: change the API of GitHub and BitBucket Sources. (#1345) (9cebf0d)
• add "engines.node" key to all packages (#1358) (b595cf0), closes #1337
• deprecate "cloudformation" namespace in favor of "CfnXxx" (#1311) (d20938c), closes #878 awslabs/jsii#283 awslabs/jsii#270
• update CloudFormation resources v2.18.0 (#1407) (0f80b56), closes #1409
• aws-codebuild: allow setting Webhook for GitHub Sources. (#1387) (d5cae61)
• aws-ec2: can now use PrefixList in ingress rules (#1360) (c3cfcd5)
• aws-iam: configure ExternalId for Role (#1359) (3d200c9), closes #235
• aws-lambda: Add python 3.7 runtime (#1379) (8c733ef)
• cdk: add the CodeDeployLambdaAlias Update Policy. (#1346) (d648b58), closes #1177
• core: convert "/" in construct id to "--" and disallow tokens (#1375) (011aac0), closes #1351 #1374
• iam: CompositePrincipal and allow multiple principal types (#1377) (b942ae5), closes #1201

BREAKING CHANGES TO EXPERIMENTAL FEATURES

• aws-cloudformation: this changes the type of the role property in CFN CodePipeline Actions from Role to IRole. This is needed to use imported Roles when creating Actions.
• aws-codebuild: this changes the API of CodeBuild's GitHub and BitBucket Sources to take an owner/repo pair instead of an entire cloneUrl, to make it consistent with the GitHubSourceAction in the CodePipeline package. Also adds handling the reportBuildStatus and insecureSsl Source properties.
• codebuild: the includeBuildID property of S3BucketBuildArtifacts was renamed to includeBuildId (note the lower-case trailing d).