Book Image

Serverless Design Patterns and Best Practices

By : Brian Zambrano
Book Image

Serverless Design Patterns and Best Practices

By: Brian Zambrano

Overview of this book

Serverless applications handle many problems that developers face when running systems and servers. The serverless pay-per-invocation model can also result in drastic cost savings, contributing to its popularity. While it's simple to create a basic serverless application, it's critical to structure your software correctly to ensure it continues to succeed as it grows. Serverless Design Patterns and Best Practices presents patterns that can be adapted to run in a serverless environment. You will learn how to develop applications that are scalable, fault tolerant, and well-tested. The book begins with an introduction to the different design pattern categories available for serverless applications. You will learn thetrade-offs between GraphQL and REST and how they fare regarding overall application design in a serverless ecosystem. The book will also show you how to migrate an existing API to a serverless backend using AWS API Gateway. You will learn how to build event-driven applications using queuing and streaming systems, such as AWS Simple Queuing Service (SQS) and AWS Kinesis. Patterns for data-intensive serverless application are also explained, including the lambda architecture and MapReduce. This book will equip you with the knowledge and skills you need to develop scalable and resilient serverless applications confidently.
Table of Contents (18 chapters)
Title Page
Copyright and Credits
Dedication
Packt Upsell
Contributors
Preface
Index

Viewing the deployed application


Learning the GraphQL language is a topic in and of itself. In this section, I'll show some queries and mutations using the Insomnia client on macOS. Insomnia is a client application that can be used to make standard REST API requests and also has a lovely GraphQL interface when working with GraphQL endpoints.

A simple query to get a list of cupping sessions, returning only the ID and name of the Sessions, looks like the following:

    query allSessions { 
      sessions {
        id
        name
      }
    }

When you think back to the implementation of the Query class, you might recall the following:

    class Query(graphene.ObjectType):
      sessions = graphene.List(SessionObject, id=graphene.Int(),    
         account_id=graphene.Int())

Hopefully, things are becoming clearer now. The preceding query is named allSessions, and inside it's explicitly asking for sessions. Our GraphQL code responds in kind by noticing that the query is for sessions and invoking...