Lambda@Edge Immutable Web App

Deploys an immutable single page web app to AWS with Serverless. All assets are served through CloudFront and index.html is generated dynamically using Lambda@Edge. Each Serverless stage selects a default app version and environment configuration using AWS Systems Manager Parameter Store, Setting the appVersion cookie will override the default. Immutable app versions are built, uploaded to S3, and published to npm. Deployment of a published version is done by updating a parameter in the store.

Development

Requirements

You will need AWS CLI, jq and Node.js with npm.

Be sure that all commands run under the correct Node version, e.g., if using nvm, install the correct version with

$ nvm install

Source code

The source code is hosted on GitHub. Clone the project with

$ git clone git@github.com:immutablewebapps/aws-lambda-edge-example.git

Initial Setup

Note: find and replace the following values in this repo with custom values to setup a completely independent project: immutablewebapps, immutableweb.app, aws-lambda-edge-example and aws-lambda-edge.

1. Setup Serverless Credentials for AWS and login to npm and add the organization name to the parameter store

   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/organization" \
     --value "immutablewebapps"
   

2. Add a hosted zone in Route53 for immutableweb.app and add the Zone ID and app domain to the parameter store with

   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/hostedZoneId" \
     --value "<zone-id>"
   

3. Create a certificate with Certificate Manager for aws-lambda-edge.immutableweb.app and *.aws-lambda-edge.immutableweb.app and add the certificate identifier to the parameter store with

   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/certificateId" \
     --value "<certificate-identifier>"
   

4. Create the parameters for the experimental stage with

   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/experimental/appDomain" \
     --value "dev.aws-lambda-edge.immutableweb.app"
   
   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/experimental/assetDomain" \
     --value "dev-assets.aws-lambda-edge.immutableweb.app"
   
   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/experimental/appVersion" \
     --value "1.0.0-rc.0"
   
   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/experimental/appConfig" \
     --value '{"title":"Lambda@Edge Immutable Web App (Experimental)","reportUri":"https://httpbin.org/post","api":"https://httpbin.org"}'
   

5. Build and deploy the initial version with

   nvm install
   npm install
   npm run build
   npm publish
   npm run deploy:assets -- --stage experimental
   npm run deploy:app -- --stage experimental
   

6. Configure and deploy the live stage with

   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/live/appDomain" \
     --value "aws-lambda-edge.immutableweb.app"
   
   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/live/assetDomain" \
     --value "assets.aws-lambda-edge.immutableweb.app"
   
   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/live/appVersion" \
     --value "1.0.0-rc.0"
   
   aws ssm put-parameter --type "String" \
     --name "/app/aws-lambda-edge/live/appConfig" \
     --value '{"title":"Lambda@Edge Immutable Web App","reportUri":"https://httpbin.org/post","api":"https://httpbin.org"}'
   
   npm run build
   npm run deploy:assets
   npm run deploy:app
   

Note: the experimental stage is completely isolated from the live stage, and should be used for testing changes to the Serverless configuration and lambda before deploying to the live stage. Otherwise, all application versions may be tested directly on the live stage.

Development Flow

Immutable asset deployment

Cut a new version with, e.g.,

npm version minor

Then either locally or on CI, publish and deploy the assets

npm install
npm run build
npm publish
npm run deploy:assets

App deployment

Deploy the app to Lambda@Edge with

npm run deploy:app

Version deployment

Once the app and assets are deployed, deploy any version by updating the corresponding parameter.

For example, use version 1.0.0-rc.0 by default on the live stage

aws ssm put-parameter --overwrite --type "String" \
  --name "/app/aws-lambda-edge/live/appVersion" \
  --value "1.0.0-rc.0"

Contributing

Please submit and comment on bug reports and feature requests.

To submit a patch:

1. Fork it (https://github.com/immutablewebapps/aws-lambda-edge-example/fork).
2. Create your feature branch (git checkout -b my-new-feature).
3. Make changes.
4. Commit your changes (git commit -am 'Add some feature').
5. Push to the branch (git push origin my-new-feature).
6. Create a new Pull Request.

License

Copyright 2018 Immutable Web Apps

The source code for this project is licensed under the Apache License, Version 2.0 (the "License"); you may not use this source code except in compliance with the License. You may obtain a copy of the License at

https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

Warranty

This software is provided by the copyright holders and contributors "as is" and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the copyright holder or contributors be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such damage.