@aws-cdk/assert

Testing utilities and assertions for CDK libraries

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This is a developer preview (public beta) module. Releases might lack important features and might have future breaking changes.

This API is still under active development and subject to non-backward compatible changes or removal in any future version. Use of the API is not recommended in production environments. Experimental APIs are not subject to the Semantic Versioning model.

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This library contains helpers for writing unit tests and integration tests for CDK libraries

Unit tests

Write your unit tests like this:

const stack = new Stack();

new MyConstruct(stack, 'MyConstruct', {
    ...
});

expect(stack).to(someExpectation(...));

Here are the expectations you can use:

Verify (parts of) a template

Check that the synthesized stack template looks like the given template, or is a superset of it. These functions match logical IDs and all properties of a resource.

matchTemplate(template, matchStyle)
exactlyMatchTemplate(template)
beASupersetOfTemplate(template)

Example:

expect(stack).to(beASupersetOfTemplate({
    Resources: {
        HostedZone674DD2B7: {
            Type: "AWS::Route53::HostedZone",
            Properties: {
                Name: "test.private.",
                VPCs: [{
                    VPCId: { Ref: 'VPC06C5F037' },
                    VPCRegion: { Ref: 'AWS::Region' }
                }]
            }
        }
    }
}));

Check existence of a resource

If you only care that a resource of a particular type exists (regardless of its logical identifier), and that some of its properties are set to specific values:

haveResource(type, subsetOfProperties)

Example:

expect(stack).to(haveResource('AWS::CertificateManager::Certificate', {
    DomainName: 'test.example.com'
    // Note: some properties omitted here
}));

Integration tests

Integration tests are modeled as CDK apps that are deployed by the developers. If deployment succeeds, the synthesized template is saved in a local file and "locked". During build, the test app is only synthesized and compared against the checked-in file to protect against regressions.

Setup

Create any number of files called integ.*.ts in your test directory. These should be CDK apps containing a single stack.

Add the following to your package.json':

{
    scripts: {
        "test": ".... && cdk-integ-assert",
        "integ": "cdk-integ"
    },
    ...
    devDependencies: {
        "@aws-cdk/assert": "*",
        "aws-cdk": "*"
    }
}

This installs two tools into your scripts:

• When npm test is executed (during build), the cdk-integ-assert tool is invoked. This tool will only synthesize the integration test stacks and compare them to the .expected files. If the files differ (or do not exist), the test will fail.
• When npm run integ is executed (manually by the developer), the cdk-integ tool is invoked. This tool will actually attempt to deploy the integration test stacks into the default environment. If it succeeds, the .expected file will be updated to include the latest synthesized stack.

The usage of cdk-integ is:

cdk-integ [--no-clean] [filters...]

# or

npm run integ -- [--no-clean] [filters...]

• If --no-clean is specified, the integration test stacks will not be cleaned up. This can be used to perform manual validation on the stacks.
• If filters are specified, each test name is evaluated against each filter. If the name matches any of the filters, the test is included. Otherwise it is skipped.

Changelog

1.8.0 (2019-09-10)

Bug Fixes

• app-delivery: action template filename incorrect (#3986) (f6ef79d), closes #3595
• certificatemanager: increase minimum validation total timeout (#3914) (4973a8c)
• custom-resources: correctly handle booleans conversion (#4000) (77105ab), closes #3933
• dynamodb: prevent "StreamARN not found for resource" errors (#3935) (617ef82)
• ecs: separate application and network load balanced services (#3719) (21eb835)
• events: fromObject handles regular and field tokens together (#3916) (b01f62d), closes #3915
• iam: only attach policies to imported roles if the accounts match (#3716) (87db7aa), closes #2985 #3025

Code Refactoring

• assets: remove content hash attribute (#4003) (181b58b)

Features

• cli: #3971 changed cdk synth to rebuild app (#3972) (198f45f)
• ec2: support configuring network ACLs (#3699) (3f10543), closes #3621
• ecr-assets: fail if tokens are used in buildArgs (#3989) (56ce9ff), closes #3981
• eks: add EKS AMis for 1.14 (#3950) (741ef43)
• eks: spot capacity and bootstrap options (#3937) (5da6b36), closes #3523 #3857 #3929 #3938 #3939
• events: allow passing a role to the CodePipeline target (#4006) (c4054ce), closes #3999

BREAKING CHANGES TO EXPERIMENTAL FEATURES

• assets: assets no longer expose a property contentHash. Use sourceHash as a good approximation. if you have a strong use case for content hashes, please raise a github issue and we will figure out a solution.
• dynamodb: fix
• ecs: The LoadBalancedServiceBase, LoadBalancedEc2Service and LoadBalancedFargateService constructs have been separated out into Application and Network LoadBalancedService constructs for both Ec2 and Fargate Services.