#REST API

Introduction

Nowadays, there is a lot of applications that are using Open Authorization framework (OAuth) to access resources from all kinds of services in a secure, reliable and efficient manner. InterSystems IRIS is already compatible with OAuth 2.0 framework, in fact, there is a great article in the community regarding OAuth 2.0 and InterSystems IRIS in the following link here.

Asymmetric cryptography is a cryptographic system that uses pairs of keys: public keys which may be disseminated widely, and private keys which are known only to the owner. The generation of such keys depends on cryptographic algorithms based on mathematical problems to produce one-way functions. Effective security only requires keeping the private key private; the public key can be openly distributed without compromising security.

In such a system, any person can encrypt a message using the receiver's public key, but that encrypted message can only be decrypted with the receiver's private key.

Robust authentication is also possible. A sender can combine a message with a private key to create a short digital signature on the message. Anyone with the sender's corresponding public key can combine the same message and the supposed digital signature associated with it to verify whether the signature was valid, i.e. made by the owner of the corresponding private key. (C) Wikipedia.

In this article, I would like to talk about the spec-first approach to REST API development.

While traditional code-first REST API development goes like this:

• Writing code
• REST-enabling it
• Documenting it (as a REST API)

Spec-first follows the same steps but reverse. We start with a spec, also doubling as documentation, generate a boilerplate REST app from that and finally write some business logic.

This is advantageous because:

• You always have relevant and useful documentation for external or frontend developers who want to use your REST API
• Specification created in OAS (Swagger) can be imported into a variety of tools allowing editing, client generation, API Management, Unit Testing and automation or simplification of many other tasks
• Improved API architecture. In code-first approach, API is developed method by method so a developer can easily lose track of the overall API architecture, however with the spec-first developer is forced to interact with an API from the position if API consumer which usually helps with designing cleaner API architecture
• Faster development - as all boilerplate code is automatically generated you won't have to write it, all that's left is developing business logic.
• Faster feedback loops - consumers can get a view of the API immediately and they can easier offer suggestions simply by modifying the spec

Let's develop our API in a spec-first approach!

InterSystems API Management (IAM) - a new feature of the InterSystems IRIS Data Platform, enables you to monitor, control and govern traffic to and from web-based APIs within your IT infrastructure. In case you missed it, here is the link to the announcement. And here's an article explaining how to start working with IAM.

In this article, we would use InterSystems API Management to Load Balance an API.

In our case, we have 2 InterSystems IRIS instances with /api/atelier REST API that we want to publish for our clients.

There are many different reasons why we might want to do that, such as:

• Load balancing to spread the workload across servers
• Blue-green deployment: we have two servers, one "prod", other "dev" and we might want to switch between them
• Canary deployment: we might publish the new version only on one server and move 1% of clients there
• High availability configuration
• etc.

InterSystems IRIS 2019.1 has been out for a while and I would like to cover some enhancements for handling JSON which might have gone unnoticed. Dealing with JSON as a serialization format is an important part of building modern applications, especially when you interact with REST endpoints.

Some time ago, InterSystems introduced the concept of %DynamicObjects.
This feature is a powerful tool that makes it very easy to convert any string of JSON text to objects and vice versa.
However, in the work that J2 Interactive is doing for our customers, there are a couple of things that "need some tweaking".

As you might have heard, we just introduced the InterSystems API Manager (IAM); a new feature of the InterSystems IRIS Data Platform™, enabling you to monitor, control and govern traffic to and from web-based APIs within your IT infrastructure. In case you missed it, here is the link to the announcement.

In this article, I will show you how to set up IAM and highlight some of the many capabilities IAM allows you to leverage.

There's a new and exciting enhancement to QEWD that has just been released - it's an additional layer of abstraction known as QEWD-Up. QEWD-Up hides away all the mechanics of QEWD itself, allowing you to focus on just your REST APIs and the code that implements them.

Additionally, and importantly, QEWD-Up simplifies the maintenance of your REST APIs, allowing you (and others) to quickly and easily understand their life-cycle and implementation.

Background

InterSystems IRIS 2019 is going to introduce new and exciting features. One of the areas with new interesting must-to-know things is the API Management.

As a result of Evgeny's recent questions regarding the use of QEWD.js with IRIS in another post, I thought it would be a good idea to create a separate post focusing specifically on how to use QEWD.js to create REST APIs for IRIS.

QEWD.js is, of course, a Node.js framework, and all the REST API code can be written entirely in JavaScript.

What if you could serialize/deserialize objects in whatever format: JSON, XML, CSV,...; attending different criteria: export/import some properties and not others, transform values in this or that way before exporting/importing,...; and all of this without having to change the class definition? Wouldn't that be great??

Well, perhaps it's a goal too ambitious to reach 100% but, exploring this idea, I've developed a bunch of classes that I thought it was good to share. If you want to test, change, modify or improve the code, or just take a look at it, you can do it here. There you'll find a more detailed explanation (see Readme.md)

Intro

For many in today's interoperability landscape, REST reigns supreme. With the overabundance of tools and approaches to REST API development, what tools do you choose and what do you need to plan for before writing any code?
This article focuses on design patterns and considerations that allow you to build highly robust, adaptive, and consistent REST APIs. Viable approaches to challenges of CORS support and authentication management will be discussed, along with various tips and tricks and best tools for all stages of REST API development. Learn about the open-source REST APIs available for InterSystems IRIS Data Platform and how they tackle the challenge of ever-increasing API complexity.
The article is a write-up for a recent webinar on the same topic.

Let’s continue our series of articles about creating a web application using REST only.

Integration with jQuery EasyUI (using datagrid and tree components as examples)

In this article I'd like to discuss asynchronous REST and approaches to implementing it.

Why do we need asynchronous REST? Simply put - answering the request takes too much time. While most requests usually can be satisfied immediately, some can't. The reasons are varied:

• You need to perform time-consuming calculations
• Performing action actually takes time (for example container creation)
• etc.

The solution to these problems is asynchronous REST. Asynchronous REST works by separating request and real response. Here's an example, let's consider the following simple async REST broker: