CONNECT TO LOCAL DYNAMODB TS HOW TO
CONNECT TO LOCAL DYNAMODB TS CODE

Our sample schema is comprised of a set of entity models for the Comment, Follow, Like, Photo and User entities. It also describes the indexes, entity keys, attributes and attribute data values and validations. The OneTable schema specifies how the entities are stored in the DynamoDB table via their DynamoDB keys. OneTable expresses the ERD as a schema that fully describes each entity and their relationships. For a particular User, we show the number of other Users following them and the number of Users they're following, as well as the ability to show the lists of Followers and 'Followees'. A Follow is a one-way relationship - a User can follow another User without the second User following in return. By following another User, you will receive updates from that User in your timeline (not implemented in this sample). When showing a Photo, we will show the total number of Comments for that Photo.Ī Follow represents one User choosing to follow another User. There is no limit to the number of Comments on a Photo by a given User. When showing a Photo, we will show the total number of Likes for that Photo.Ī Comment represents a User commenting on a particular Photo. A specific Photo may only be liked once by a specific User. Each photo is uniquely indexed by a photoId and a user name.Ī Like represents a specific User liking a specific Photo. A photo keeps a count of the number of comments and likes.

Each Photo can be Liked or Commented on (see below). You can browse all Photos for a particular User in reverse-chronological order. A count of followers and people followed by the user is kept in followers and following.Ī Photo represents an image uploaded by a particular User. They will be uniquely identified by a user name in the user attribute. Here is the ERD for the sample database schema with 5 entities: User, Follow, Like, Photo and Comment.Ī User represents a person that has signed up for the application. You can read more in my post Data Modeling for Single Table Designs. The sample follows a Single-Table design pattern where all the database entities are stored together in a single DynamoDB table. A user may also choose to follow another user in order to see their recent activity. This sample is an Instagram backend clone where users can post photos and other users may like a photo or comment on a photo. Getting Startedīefore comparing the two implementations, it is worth providing a quick design overview so you understand the sample design and concepts.

CONNECT TO LOCAL DYNAMODB TS HOW TO

See the sample README which describes how to checkout the sample from GitHub and how to run locally using the Serverless framework and VS Code.

CONNECT TO LOCAL DYNAMODB TS CODE

The code for the OneTable variation is available at GitHub senseDeep/dynamodb-instagram-blog and you can find the original app at GitHub alexdebrie/dynamodb-instagram. If the OneTable design is simpler or cleaner, that is the result of the additional services offered by OneTable and not by any better coding on my part. I personally learned several new things while doing this comparison - thank you Alex. This post will do a side-by-side comparison of OneTable and original native DynamoDB implementations of this Instagram sample.ĭisclaimer: The original code is clean, consistent and a well executed sample that is an excellent guide for creating a DynamoDB application. It make DynamoDB single table design patterns simpler and provides a terse, flexible API. OneTable is a DynamoDB access library for NodeJS that makes dealing with DynamoDB faster, easier and less error prone. The sample he used is an excellent introduction to DynamoDB and demonstrates how to organize an app when using DynamoDB.Īs a fun exercise, I wanted to see how this sample app would be changed, simplified and potentially made easier to maintain by using the OneTable DynamoDB library. In that video, Alex covers the key basics of DynamoDB including data modeling, one-to-many relationships, single-table design and the core DynamoDB API. Alex DeBrie, author of the DynamoDB Book, created a sample Instagram backend for DynamoDB, as part of a video he did with Marcia Villalba for the FooBar Channel.

Connect to local dynamodb ts