DocumentDB and MongoDB
Using JSON-like storage
As an alternative to DynamoDB, you can use a JSON-style document store. You can use a normal MongoDB client (like node's
mongodb ) to connect all three of these. Follow the node MongoDB documentation.
AWS has more recently included DocumentDB, a MongoDB compatible database for storing JSON-like documents. However unlike DynamoDB, DocumentDB requires persistent large EC2 instances to be deployed and running continuously. As a result DocumentDB can be very expensive even if you're not using it much.
MongoDB Atlas in AWS
MongoDB inc also provide MongoDB Atlas, which has a free tier. Note the free tier (M0) is only available in certain AWS regions - at the time of writing
eu-central-1. MongoDB Atlas also has lower pricing than DocumentDB.
MongoDB Server in the Arc Sandbox
You can install MongoDB server and use it from the Arc sandbox.
In the sandbox, you'll need to close DB connections for your lambdas to complete. This is a limit of the current sandbox and should go away in future.
DocumentDB/Mongo in AWS
In your lambdas (and, as of Architect Functions version 4, your middleware), use:
context.callbackWaitsForEmptyEventLoop = false
this will re-use the connection on the next lambda invocation (if AWS can re-use the same Lambda container)