Construct Hub

This project maintains a AWS Cloud Development Kit construct library that can be used to deploy instances of the Construct Hub in any AWS Account.

This software backs the public instance of the ConstructHub, and can be used to deploy a self-hosted instance with personalized configuration.

❓ Getting Started

Warning

Disclaimer

The public instance of ConstructHub is Generally Available.

Self-hosted ConstructHub instances are however in active development and should be considered experimental. Breaking changes to the public API of this package are expected to be released without prior notice, and the infrastructure and operational posture of ConstructHub instances may also significantly change.

You are welcome to deploy self-hosted instances of ConstructHub for evaluation purposes, and we welcome any feedback (good or bad) from your experience in doing so.

Important

💰 Cost of running Construct Hub

If you opt to use Construct Hub for processing your CDK packages, you will be subject to charges based on the number of packages processed by Construct Hub. To minimize these charges, you can implement package filters for relevant sources and exclude public NPM packages from the processing list.

Quick Start

Once you have installed the construct-hub library in your project, the simplest way to get started is to create an instance of the ConstructHub construct:

import { App, Stack } from 'aws-cdk-lib/core';
import { ConstructHub } from 'construct-hub';

// The usual... you might have used `cdk init app` instead!
const app = new App();
const stack = new Stack(app, 'StackName', { /* ... */ });

// Now to business!
new ConstructHub(stack, 'ConstructHub');

Personalization

Using a custom domain name

In order to use a custom domain for your ConstructHub instance instead of the default CloudFront domain name, specify the domain property with the following elements:

Attribute	Description
zone	A Route53 Hosted Zone, where DNS records will be added.
cert	An Amazon Certificate Manager certificate, which must be in the us-east-1 region.
monitorCertificateExpiration	Set to false if you do not want an alarm to be created when the certificate is close to expiry.

Your self-hosted ConstructHub instance will be served from the root of the provided zone, so the certificate must match this name.

Alternate package sources

By default, ConstructHub has a single package source configured: the public npmjs.com registry. Self-hosted instances typically should list packages from alternate sources, either in addition to packages from npmjs.com, or instead of those.

The packageSources property can be used to replace the default set of package sources configured on the instance. ConstructHub provides IPackageSource implementations for the public npmjs.com registry as well as for private CodeArtifact repositories:

import * as codeartifact from 'aws-cdk-lib/aws-codeartifact';
import { App, Stack } from 'aws-cdk-lib/core';
import { sources, ConstructHub } from 'construct-hub';

// The usual... you might have used `cdk init app` instead!
const app = new App();
const stack = new Stack(app, 'StackName', { /* ... */ });

// Now to business!
const repository = new codeartifact.CfnRepository(stack, 'Repository', {
  domainName: 'my-domain',
  repositoryName: 'my-repo',
  // ....
});
new ConstructHub(stack, 'ConstructHub', {
  packageSources: [
    new sources.NpmJs(), // Remove if you do NOT want npmjs.com packages
    new sources.CodeArtifact({ repository }),
  ],
});

You may also implement a custom IPackageSource if you want to index packages from alternate locations. In this case, the component you provide will be responsible for sending notifications to an SQS Queue about newly discovered packages. You may refer to the sources.NpmJs and sources.CodeArtifact implementations as a reference for hos this can be done.

By default, download counts of NPM packages will be fetched periodically from NPM's public API by a Lambda. Since this is not desirable if you are using a private package registry, this is automatically disabled if you specify your own value for packageSources. (But this can be re-enabled through the fetchPackageStats property if needed).

Package deny list

Certain packages may be undesirable to show in your self-hosted ConstructHub instance. In order to prevent a package from ever being listed in construct hub, the denyList property can be configured with a set of DenyListRule objects that specify which package or package versions should never be lested:

import { App, Stack } from 'aws-cdk-lib/core';
import { ConstructHub } from 'construct-hub';

// The usual... you might have used `cdk init app` instead!
const app = new App();
const stack = new Stack(app, 'StackName', { /* ... */ });

// Now to business!
new ConstructHub(stack, 'ConstructHub', {
  denyList: [
    // Denying _all_ versions of the "sneaky-hackery" package
    { packageName: 'sneaky-hackery', reason: 'Mines bitcoins wherever it gets installed' },
    // Denying _a specific_ version of the "bad-release" package
    { packageName: 'bad-release', version: '1.2.3', reason: 'CVE-####-#####' },
  ],
});

Redirecting from additional domains

You can add additional domains that will be redirected to your primary Construct Hub domain:

import * as r53 from 'aws-cdk-lib/aws-route53';

const myDomainZone = r53.HostedZone.fromHostedZoneAttributes(this, 'MyDomainZone', {
  hostedZoneId: 'AZ1234',
  zoneName: 'my.domain.com',
});

new ConstructHub(this, 'ConstructHub', {
  additionalDomains: [ { hostedZone: myDomainZone } ]
});

This will set up full domain redirect using Amazon S3 and Amazon CloudFront. All requests will be redirected to your primary Construct Hub domain.

Decrease deployment footprint

By default, ConstructHub executes the documentation rendering process in the context of isolated subnets. This is a defense-in-depth mechanism to mitigate the risks associated with downloading aribtrary (un-trusted) npm packages and their dependency closures.

This layer of security implies the creation of a number of resources that can increase the operating cost of your self-hosted instance: several VPC endpoints are created, an internal CodeArtifact repository needs to be provisioned, etc...

While we generally recommend leaving these features enabled, if your self-hosted ConstructHub instance only indexes trusted packages (as could be the case for an instance that does not list packages from the public npmjs.com registry), you may set the isolateLambdas setting to false.

⚙️ Operating a self-hosted instance

1. Application Overview provides a high-level description of the components that make a ConstructHub instance. This is a great starting point for people who consider operating a self-hosted instance of ConstructHub; and for new operators on-boarding the platform.

2. Operator Runbook is a series of diagnostics and troubleshooting guides indended for operators to have a quick and easy way to navigate a ConstructHub instance when they are reacting to an alarm or bug report.

🐤 Deployment Canaries

Construct Hub provides several built-in validation mechanisms to make sure the deployment of your instance is continuously operating as expected.

These mechanisms come in the form of canary testers that are part of the ConstructHub deployment stack. Each canary runs periodically and performs a different check, triggering a different CloudWatch alarm in case it detects a failure.

We recommend that you use staged deployments, and block promotions to the production stage in case any preivous stage triggers an alarm within a specific timeframe.

Discovery Canary

When configuring an NpmJs package source, a package discovery canary can be enabled using the enableCanary property (and optionally configured using the canaryPackage and canarySla properties). This feature is activated by default and monitors availability of releases of the construct-hub-probe npm package in the ConstructHub instance.

Probe packages, such as construct-hub-probe are published frequently (e.g: every 3 hours or more frequently), and can be used to ensure the ConstructHub instance correctly discovers, indexes and represents those packages.

If a different package or SLA should be used, you can configure the NpmJs package source manually like so:

import * as codeartifact from 'aws-cdk-lib/aws-codeartifact';
import { App, Duration, Stack } from 'aws-cdk-lib/core';
import { sources, ConstructHub } from 'construct-hub';

const app = new App();
const stack = new Stack(app, 'StackName', { /* ... */ });

new ConstructHub(stack, 'ConstructHub', {
  // ...
  packageSources: [
    // ...
    new sources.NpmJs({
      enableCanary: true, // This is the default
      canaryPackage: '@acme/my-constructhub-probe',
      canarySla: Duration.minutes(30),
    }),
    // ...
  ],
  // ...
});

In case the new package isn't fully available in the predefined SLA, a high severity CloudWatch alarm will trigger, which will in turn trigger the configured action for low severity alarms.

See Monitoring & Alarms

The operator runbook contains instructions on how to diagnose and mitigate the root cause of the failure.

💅 Customizing the frontend

There are a number of customizations available in order to make your private construct hub better tailored to your organization.

Package Tags

Configuring package tags allows you to compute additional labels to be applied to packages. These can be used to indicate to users which packages are owned by trusted organizations, or any other arbitrary conditions, and can be referenced while searching.

For example:

new ConstructHub(this, "ConstructHub", {
  packageTags: [{
    id: 'official',
    condition: TagCondition.field('name').eq('construct-hub'),
    keyword: {
      label: 'Official',
      color: '#00FF00',
    },
    highlight: {
      label: 'Vended by AWS',
      color: '#00FF00',
    }
  }]
});

The above example will result in packages with the name of construct-hub to receive the Official tag, which is colored green and displayed amongst the list of keywords. Additionally the highlight key shows this as a highlighted item on the package's card.

The searchFilter key can also be used to show tags as search filters grouped together.

const authorsGroup = new PackageTagGroup("authors", {
  label: "Authors",
  tooltip: "Information about the authors filter",
  filterType: FilterType.checkbox(),
});

const isAws = TagCondition.field('name').eq('construct-hub');
new ConstructHub(this, "ConstructHub", {
  packageTags: [{
    id: 'AWS',
    condition: isAws,
    searchFilter: {
      group: authorsGroup,
      display: 'AWS',
    },
  }, {
    id: 'Community',
    condition: TagCondition.not(isAws),
    searchFilter: {
      group: authorsGroup,
      display: 'AWS',
    },
  }]
});

The above will show a list of Authors filters on the search results page with a checkbox for each AWS and Community packages, allowing users to filter results by the presence of these tags.

Combinations of conditions are also supported:

new ConstructHub(this, "ConstructHub", {
  packageTags: [{
    id: 'official',
    keyword: {
      label: 'Official',
      color: '#00FF00',
    },
    condition: TagCondition.or(
      TagCondition.field('name').eq('construct-hub'),
      TagCondition.field('name').eq('construct-hub-webapp'),
    ),
  }]
});

You can assert against any value within package json including nested ones.

TagCondition.field('constructHub', 'nested', 'key').eq('value');

// checks the following:
// packageJson?.constructHub?.nested?.key === value;

You can also assert that a string occurs at least a certain number of times within the package's README.

TagCondition.readme().includes('ECS');
TagCondition.readme().includes('fargate', { atLeast: 3, caseSensitive: false });

Package Links

Configuring package links allows you to replace the Repository, License, and Registry links on the package details page with whatever you choose.

For example:

new ConstructHub(this, "ConstructHub", {
  packageLinks: [{
    linkLabel: 'Service Level Agreement',
    configKey: 'SLA',
  }, {
    linkLabel: 'Contact',
    configKey: 'Contact',
    linkText: 'Email Me!',
    allowedDomains: ['me.com'],
  }]
});

This would allow publishers to add the following to their package.json:

"constructHub": {
  "packageLinks": {
    "SLA": "https://support.mypackage.com",
    "Contact": "me.com/contact"
  }
}

Then the links on the corresponding package page would show these items as configured.

RSS/ATOM feeds for recent packages

Construct hub automatically generates RSS/ATOM feed showing the list of latest 100 packages added. The generated feed can be configured to get release notes from GitHub by configuring it with personal access token. The access token has to be stored in AWS Secretsmanager and should be passed to feedConfiguration

For example:

new ConstructHub(this, "ConstructHub", {
  feedConfiguration: {
      githubTokenSecret: secretsmanager.Secret.fromSecretCompleteArn(this, 'GitHubToken', '<arn:aws:secretsmanager:us-east-2:11111111111:secret:releaseNotesFetcherGitHubToken-abCd1>'),
      feedDescription: 'Latest Constructs in the construct hub',
      feedTitle: 'Latest constructs',
    }
  }
);

Home Page

The home page is divided into sections, each with a header and list of packages. Currently, for a given section you can display either the most recently updated packages, or a curated list of packages.

For example:

new ConstructHub(this, "ConstructHub", {
  featuredPackages: {
    sections: [
      {
        name: "Recently updated",
        showLastUpdated: 4
      },
      {
        name: "From the AWS CDK",
        showPackages: [
          {
            name: "@aws-cdk/core"
          },
          {
            name: "@aws-cdk/aws-s3",
            comment: "One of the most popular AWS CDK libraries!"
          },
          {
            name: "@aws-cdk/aws-lambda"
          },
          {
            name: "@aws-cdk/pipelines",
            comment: "The pipelines L3 construct library abstracts away many of the details of managing software deployment within AWS."
          }
        ]
      }
    ]
  }
});

Browse Categories

The Construct Hub home page includes a section that displays a set of buttons that represent browsing categories (e.g. "Databases", "Monitoring", "Serverless", etc).

You can use the categories option to configure these categories. Each category is defined by a title and a url, which will be the link associated with the button.

new ConstructHub(this, "ConstructHub", {
  categories: [
    { title: 'Databases', url: '?keywords=databases' },
    { title: 'Monitoring', url: '?q=monitoring' },
    { title: 'Partners', url: '?tags=aws-partner' }
  ]
});

Feature Flags

Feature flags for the web app can be used to enable or disable experimental features. These can be customized through the featureFlags property - for more information about the available flags, check the documentation for https://github.com/cdklabs/construct-hub-webapp/.

AppRegistry

By default, an AppRegistry application will be created that is associated with the stack you put the ConstructHub construct in.

Re-processing specific packages

In some cases, you might need to re-generate the documentation for a given package version. This is useful, for example, in a CI/CD pipeline, to make sure there are no regressions before releasing a new version to production.

To re-process a specific package, start the execution of the state machine called ReprocessDocumentationPerPackage with the following input:

{
  "Prefix": "data/<package-name>/v<package-version>"
}

✋ Contributing

If you are looking to contribute to this project, but don't know where to start, have a look at our contributing guide!

👮 Security

See CONTRIBUTING for more information.

⚖️ License

This project is licensed under the Apache-2.0 License.