In this article we will explore the Observer Pattern in JavaScript. We will look at a real world example that involves processing order shipment and how to implement observer pattern in that context. In object oriented programming the Observer Pattern defines a one-to-many dependency between objects, where one object (the subject or observable) maintains a…
The Strategy Pattern is a powerful design pattern in JavaScript that allows you to define a family of algorithms, encapsulate each one as a separate object, and make them interchangeable. This pattern is especially useful when you want to select an algorithm’s implementation at runtime without altering the client code. In this article, we explore how the Strategy Pattern works in JavaScript, providing practical examples to demonstrate its flexibility and scalability in solving various problems.
In the post about REST API Filtering we have getFilterBy method in BaseRepository that calls getSequelizeWhereClause function and returns result. The call is wrapped up in try…catch block, so when an error is thrown, it gets transformed into an API error and get re-thrown. The message from the original error is assigned to the API…
In this article we will look at how to implement advanced filtering in REST API when a GET request a list of results. In our API project that will be GET /v1/travels and GET /v1/tours endpoints. Although setup for filtering is similar to sorting, the implementation is a bit more complex. First we are going…
In this article we will look at how to sort results when using a GET request that returns a list. Implementing sorting functionality in a RESTful API is a crucial aspect of designing a robust and user-friendly web service. Sorting REST API results empowers developers and end-users alike by providing a systematic and organized way…
In this article we will look at how to use Sequelize seeders to seed the database with test data and use Faker library to generate the test data. We will continue working in the project travel-api-db-migration-service we created in the video Sequelize Migrations. Please, watch that video if you would like to see how the…
In this article we will look at REST API Delete operation. Compared to Create and Update, Delete operation is fairly easy and straightforward. REST API Delete Implementation Below, we will outline the basic steps of Delete operation implementation. Please, watch our video for more in depth explanation of this concept. Route and Controller In routes/v1/travels…
In the previous article REST API Request Validation we looked at how to create a resource using POST request and Joi validation. In this article we will look at how to use REST API Update operation to modify a resource. We will also be using Joi validation to ensure security and consistency. Compared to creation,…
In this article we will look at how to validate POST requests to the REST API using Joi library. Joi lets you describe your data using a simple, intuitive, and readable language. We will also look at how to turn Joi errors into 422 Validation Error API responses. Describe REST API Request Shema with Joi…
In the previous post HMAC Validation we explored how to validate HMAC in an API project. The video Webhooks Processing: HTTP API Gateway + SQS +Lambda shows how to created a scalable solution for receiving webhooks and throttling them with SQS and Lambda. In this article we will look at how to use HMAC Validation…