VTDLP Resolution Service

This project contains source code and supporting files for a serverless application - VTDLP resolution service. This service resolves VTDLP's permanent link. For example, it redirects http://idn.lib.vt.edu/ark:/53696/kr10gt01 to https://iawa.lib.vt.edu/archive/kr10gt01.

The application uses several AWS resources, including Lambda functions and an API Gateway API. These resources are defined in the template.yaml file in this project.

Lambda Function

• app.py: Handle URL redirection

API Gateway

• GET https://xxxx.execute-api.us-east-1.amazonaws.com/Prod/{arklabel}/53696/{shortid}
  • arklabel: ark:
  • shortid: Noid

DynamoDB Table

• Table Schema
• Sample record

Deploy VTDLP Resolution Service application using CloudFormation stack

Step 1: Launch CloudFormation stack

Click Next to continue

Step 2: Specify stack details

Name	Description
Stack name	any valid name
TargetTable	a DynamoDB table
Image404	404 Image URL
REGION	a valid AWS region. e.g. us-east-1

Step 3: Configure stack options

Leave it as is and click Next

Step 4: Review

Make sure all checkboxes under Capabilities section are CHECKED

Click Create stack

Deploy VTDLP Resolution Service application using SAM CLI

To use the SAM CLI, you need the following tools.

• SAM CLI - Install the SAM CLI
• Python 3 installed
• Docker - Install Docker community edition

To build and deploy your application for the first time, run the following in your shell:

sam build --use-container

Above command will build the source of the application. The SAM CLI installs dependencies defined in requirements.txt, creates a deployment package, and saves it in the .aws-sam/build folder.

To package the application, run the following in your shell:

sam package --output-template-file packaged.yaml --s3-bucket BUCKETNAME

Above command will package the application and upload it to the S3 bucket you specified.

Run the following in your shell to deploy the application to AWS:

sam deploy --template-file packaged.yaml --stack-name STACKNAME --s3-bucket BUCKETNAME --parameter-overrides 'TargetTableName=resolutiontable Region=us-east-1 Image404=https://images/404.jpg' --capabilities CAPABILITY_IAM CAPABILITY_NAMED_IAM --region us-east-1

Postdeployment

• URL redirection

curl https://xxxxx.execute-api.us-east-1.amazonaws.com/Prod/ark:/53696/kr10gt01

• Output

{"statusCode": 301, "location": "https://iawa.lib.vt.edu/archive/kr10gt01"}

ps. Setting up custom domain names (e.g. http://idn.lib.vt.edu ) for REST APIs. Guide

Tests

Tests are defined in the tests folder in this project. Use PIP to install the test dependencies and run tests. You must have a env file: custom_pytest.ini

lambdatest$ pip install -r tests/requirements.txt --user
# unit test
lambdatest$ python -m pytest tests/unit -v -c custom_pytest.ini

Cleanup

To delete the sample application that you created, use the AWS CLI. Assuming you used your project name for the stack name, you can run the following:

aws cloudformation delete-stack --stack-name resolution-service