Podcast RSS Generator

An AWS stack that creates lambda function to generate an up to date RSS feed document whenever a new podcast episode is deposited into the VT Digital Library Platform.

Techniques

• The generated lambda function is triggered when a new record is created in the DynamoDB Archive table that is specified in the deployment.
• The lambda function checks if the new record is in the "podcasts" item category. The script will only continue if it is a podcast record.
• The lambda function generates the RSS feed info for the podcast collection that the new podcast episode belongs to and writes this info to the s3 bucket specified in the deployment

Deployment

You can use two different methods to deploy VTDLP Services. The first method is using CloudFormation stack and the second method is using SAM CLI.

Deploy VTDLP Services using CloudFormation stack

Step 1: Launch CloudFormation stack

Click Next to continue

Step 2: Specify stack details

• Stack name: Stack name can include letters (A-Z and a-z), numbers (0-9), and dashes (-).

• Parameters: Parameters are defined in your template and allow you to input custom values when you create or update a stack.

Name	Description	Note
ArchiveStream	a DynamoDB Archive table stream name. This is the value following the final backslash in Latest stream ARN under "DynamoDB stream details". Example: 2020-09-18T16:55:17.247	Required
ArchiveTable	a DynamoDB table name of type Archive	Required
BucketName	A valid S3 bucket name	Required
CollectionTable	a DynamoDB table name of type Collection	Required
Region	a valid AWS region. e.g. us-east-1	Required

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

Step 5: Finish

After cloudformation is deployed successfully, you can see podcastRSSGenerator, podcastRSSGeneratorRole, and podcastRSSGeneratorStream information in the Resources tab.

Deploy the app using AWS 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:

• Clone the repo to your local system

git clone https://github.com/VTUL/PodcastRSSGenerator.git

• From the root of the repository run the Makefile to install python dependencies

cd path/to/PodcastRSSGenerator/
make

• Build the project

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.

• Package the project for deployment

sam package \
  --template-file template.yml \
  --output-template-file package.yml \
  --s3-bucket YOUR_S3_BUCKET_NAME

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

• Deploy the project to AWS

sam deploy --template-file packaged.yaml --stack-name YOUR_STACK_NAME --s3-bucket YOUR_S3_BUCKET_NAME --parameter-overrides 'Region=us-YOUR_REGION CollectionTable=YOUR_DYNAMODB_COLLECTION_TABLE_NAME ArchiveTable=YOUR_DYNAMODB_ARCHIVE_TABLE_NAME ArchiveStream=YOUR_ARCHIVE_STREAM BucketName=YOUR_S3_BUCKET_NAME' --capabilities CAPABILITY_IAM --region YOUR_REGION

The above command will package and deploy your application to AWS, with a series of prompts:

• Stack Name (STACKNAME): (Required) The name of the AWS CloudFormation stack that you're deploying to. If you specify an existing stack, the command updates the stack. If you specify a new stack, the command creates it. This should be unique to your account and region, and a good starting point would be something matching your project name. Stack name can include letters (A-Z and a-z), numbers (0-9), and dashes (-).
• S3 Bucket (BUCKETNAME): (Required) An Amazon S3 bucket name where this command uploads your AWS CloudFormation template. S3 bucket name is globally unique, and the namespace is shared by all AWS accounts. See Bucket naming rules. This S3 bucket should be already exist and you have the permission to upload files to it.
• Parameter Overrides: A string that contains AWS CloudFormation parameter overrides encoded as key-value pairs. For example, ParameterKey=ParameterValue NSTableName=DDBTableName.

  Name	Description	Note
  ArchiveStream	a DynamoDB Archive table stream name. This is the value following the final backslash in Latest stream ARN under "DynamoDB stream details". Example: 2020-09-18T16:55:17.247	Required
  ArchiveTable	a DynamoDB table name of type Archive	Required
  BucketName	A valid S3 bucket name	Required
  CollectionTable	a DynamoDB table name of type Collection	Required
  Region	a valid AWS region. e.g. us-east-1	Required

Cleanup

If you'd like to tear down the project & delete all of the resources created by this project, you can run the following:

aws cloudformation delete-stack --stack-name YOUR_STACK_NAME

Communication

• GitHub issues: bug reports, feature requests, install issues, thoughts, etc.
• Email: digital-libraries@vt.edu

Releases and Contributing

We have a 30 day release cycle (We do Sprints!). Please let us know if you encounter a bug by filing an issue. We appreciate all contributions.

If you are planning to contribute back bug-fixes, please do so without any further discussion.

If you plan to contribute new features, utility functions or extensions to the core, please first open an issue and discuss the feature with us.

To learn more about making a contribution, please see our Contribution page.

The Team

DLP Access Website is currently maintained by Yinlin Chen, Lee Hunter, and Andrea Waldren.