Unveiling WSO2 API Manager 4.0 — A Giant Leap for API-led Integration

WSO2 API Manager 4.0

These are difficult times for all of us. The pandemic has forced all of us to look at things differently and as a result, we had to change the way we live, the way we learn, the way we work, and even the way we do our businesses.

Now everything revolves around the theme — “Stay Home, Stay Safe.!”, and it is a time we try to consume everything remotely, staying at home. The era of attracting or inviting users/ consumers/ visitors to come to the Service Providers, and consume the services is gone and it’s time to deliver everything to the consumers’ doorstep. It’s time for products and services companies, universities, financial institutions, hospitals & pharmacies, etc. to deliver their products and services to consumers’ doorstep.

To get through these difficult times by adapting to the new norm, organizations have to embrace digital transformation, and businesses have to work hard to maintain a competitive edge through continuous innovation and keep innovating further. This is not the time that consumers go and shop around and pick/ consume what they want from many different places and it is the time businesses sell packaged products and services. This is done mainly through Integration which means businesses have to integrate within and outside.

The integration is not a new thing and the purpose of this post is not to talk about the integration as it has been there for decades. We have experienced both positives and negatives with the traditional integration approaches for the last few decades, and what we need nowadays is API-led Integration.

Some critical considerations in providing API-led integrations include combining different services, dealing with multiple protocols, and supporting a diverse set of infrastructures. To address these considerations, Enterprises came looking for Enterprise Service Bus (ESBs) and it handled most of the challenges we faced in Enterprise Integration.

Once those different services are combined (or integrated), the final product will be offered as an API. The APIs are the main building blocks of today’s service-based industry. As a result, the Enterprises went looking for API Management platforms that offer this final product (APIs) to the consumers by providing appropriate measures in place ensuring improved customer support.

The below diagram showcases how we delivered APIs and Enterprise Integration by combining API Manager and Enterprise Service Bus (ESB) platforms.

API-led Integration using API Manager and Enterprise Integrator

However, often we noticed that most of the enterprises did not know the tight coupling between APIs and Integration so some came looking for API Management when what they really need is the Enterprise Integrations, and some came looking for Enterprise Integration when what they really need is API Management. As a result, they ended up having either a wrong solution in place or addressing only a subset of the solution.

Both of these aspects — creating and integrating services (Service Integration) and exposing them in a structured manner (API Management) must be carefully considered because when developing digital platforms (and products) to meet customer demands, a wide variety of services which are running on a number of platforms and environments must be integrated into different ways.

Having to create integration services manually from scratch to cater to business requirements is a time-consuming and cost-inefficient task and there should be an organized method to design, implement and combine services. That’s is where ESBs like WSO2 Enterprise Integrator come to the rescue.

Having to create, design, and publish APIs manually from scratch to expose integration services is a time-consuming and cost-inefficient task and there should be an organized method to create, design, and publish APIs. That’s is where API Management like WSO2 API Manager comes to the rescue.

Today we have combined the power of both WSO2 API Manager and WSO2 Enterprise Integrator into a single product — WSO2 API Manager 4.0 to provide first-class API-led Integration. WSO2 API Manager 4.0 is offered as a solution that can facilitate service design, service creation, service integration, API development, and exposing APIs seamlessly.

API Manager 4.0 — One Platform for API Management, Integration, and Event-Driven Architecture

WSO2 API Manager 4.0 delivers a seamless, end-to-end API Management experience for all different personas in the API Management space including API creators, product managers, and consumers. Not only the API Management capabilities, but API Manager 4.0 also includes Service Integration capabilities into the same product by inheriting all the capabilities of WSO2 Enterprise Integrator — one of the oldest hybrid, cloud- and container-native integration platforms (ESB) in the market. WSO2 API Manager 4.0 combines the power of three distinct profiles:

  • API Manager — provides the full API management life cycle capabilities traditionally provided by WSO2 API Manager.
  • Micro Integrator — brings the support for integration capabilities required for both microservices-style architectural approaches and traditional centralized (ESB-style) integration architectures.
  • Streaming Integrator — brings the support for implementing streaming extract, transform load (ETL) and change data capture (CDC) solutions, as well as process large files and real-time APIs. It also brings the support for connecting to and enabling event-driven architectures with distributed streaming systems, such as Kafka and Amazon Simple Queue Service (SQS).

A picture is worth a thousand words. So, let's try to understand what a giant leap the WSO2 API Manager 4.0 release is by looking at the below product architecture diagrams.

Before API Manager 4.0

WSO2 API Manager 3.2 — below is the high-level product composition/ architecture of the WSO2 API Manager 3.2 release and it provides a lot of first-class capabilities for API Management.

WSO2 API Manager 3.2 — Componentized Overview

WSO2 Enterprise Integrator 7.1 — below is the high-level product composition/ architecture of the WSO2 Enterprise Integrator 7.1 release and it provides all the capabilities required for enterprise integration including service integrations, data integration, support for microservices architecture, etc.

WSO2 Enterprise Integrator 7.1 — Ecosystem Overview

WSO2 Streaming Integrator 7.1 — below is the high-level product composition/ architecture of the WSO2 Streaming Integrator 7.1 release and it provides all the capabilities required for real-time ETL, support for streaming systems, streaming data integration, etc.

WSO2 Streaming Integrator — Ecosystem Overview

WSO2 API Manager 4.0 = API Manager + Enterprise Integrator + Streaming Integrator + much more …— beyond just API management

As you can see below, WSO2 API Manager 4.0 release combines the power of its predecessor products — API Manager, Enterprise Integrator, and Streaming Integrator, and much more.

WSO2 API Manager 4.0 — Componentized Overview

Apart from all the existing exciting features, below are some of the additions/ enhancements to the API Manager 4.0 release:

  • Facilitating Event-Driven Architectures — WSO2 API Manager 4.0 adds the support for implementing applications based on streaming and event-driven architectures. It includes support for AsyncAPI specification, streaming APIs, Server-Sent Events protocol, WebSocket APIs, and webhook APIs.
  • Support for AsyncAPI Specification — with the adaptation of the OpenAPI specification, the AsyncAPI specification defines a standard API format for event-driven APIs. It is a major advance in the world of API standardization. WSO2 API Manager 4.0 is the first to provide full out-of-the-box AsyncAPI support for WebSockets, Webhooks, and SSE. AsyncAPI support for additional protocols is available via WSO2’s adapters for Kafka, RabbitMQ, ActiveMQ, and others.
  • Streaming APIs — with WSO2 API Manager 4.0, developers can expose an event stream as a managed API. With this it lets you expose event streams and topics as managed APIs via web-friendly protocols (WebSockets, SSE, and WebSub). All the QoS aspects, such as security, access control, and throttling can be applied on top of these streaming APIs just like we do with any other traditional REST APIs.
  • Support for Server-Sent Event Messaging Protocol — SSE is an HTTP-based protocol with lower latency (delivery latency) than standard HTTP. With WSO2 API Manager 4.0, developers can link an API to a Server-Sent Event (SSE) backend and receive events from the backend.
  • WebSocket API — WebSocket APIs are APIs that provide the ability to send events (messages) continuously in a full-duplex manner over a channel that is established once, making it possible to receive event-driven messages without having to poll the server for a reply. With WSO2 API Manager 4.0, WebSocket endpoints can now be exposed as managed Streaming APIs. And it supports all the other existing API Management capabilities such as capabilities, such as API lifecycle management, throttling, and analytics.
  • Webhook APIs — Webhooks is a method of pushing events of a web application or a website to registered callback URLs. Webhooks only allows one-way communication- from a caller web app to the registered web application. With WSO2 API Manager 4.0, API Developers can expose Webhooks as managed APIs. And Webhooks providers which are exposed as managed APIs also can leverage other existing API Management capabilities such as monetization, monitoring, security, and access control.
  • Swagger/GraphQL to Postman Collection — Postman is a very popular tool and must-have tool in your collection. It is the most popular testing tool among API Developers for testing REST/HTTP APIs. Postman allows developers to create API test projects, called Postman collections. With WSO2 API Manager 4.0, Postman collections can be exported from the Developer Portal through the API try-out console, and the exported postman collections can be executed with the Postman tool, allowing users to quickly test APIs. This function is available for both REST and GraphQL APIs.
Swagger/ GraphQL to Postman Collection
  • Service Catalogue API — with this, API Owners can now conveniently expose Integration Services as Managed APIs in the API Marketplace (Developer Portal). This enables publishing services created using Micro Integrator or Streaming Integrator along with other services. An API Developer can easily discover all available services and build a Managed API with a click of a button and multiple APIs can be created from a single service.
Service Catalog
  • API and API Product Revision Support — in earlier versions of API Manager, if we are making a change or an improvement to an existing API using the API Publisher portal, the changes were immediately saved into the Gateway and as a result, in a Production environment, if the changes applied aren’t thoroughly tested/ verified, serious problems can arise. The Revisioning feature of API Manager 4.0 will help us to mitigate this issue. It includes a new feature called API Revisioning, which allows an API developer to make improvements to an existing API and evaluate them without impacting existing API deployments. If the changes are not acceptable or causing an issue, we do have an option of reverting the changes to a previous/ stable Revision.
API and API Product Revision Support
  • 3rd Party Key Manager Support — starting from the API Manager 3.1 release, it started providing the support for different authorization servers to act as Key Managers. API Manager 4.0 adds support for more 3rd party authorization servers available in the industry.
  • Cloud-based Analytics — Analytics has a brand-new story with the API Manager 4.0 release. Yes, it’s cloud-based and it adds rich, new cloud-based analytics to let developers and managers see how their APIs and applications are being used. Users can simply create an account in the WSO2 Cloud and connect to the analytics. As usual, enterprises can continue to take advantage of out-of-the-box support for Google Analytics provided by WSO2 API Manager, as well as plug-in third-party analytics systems depending on their choice.
  • VHost Feature — this is a new capability that lets APIs be exposed using unique hostnames that correspond to a Gateway environment. This capability lets API publishers use the VHosts to group their APIs by selecting a virtual host. And, application developers can access APIs by using defined access URLs of the virtual host. Admin Portal will be used to manage Gateway environments by building, upgrading, and deleting them.


Today, Enterprises can no longer operate in silos and they need to integrate within and outside to provide meaningful, competitive products and services. Earlier, they had to leverage multiple products/ platforms to provide API Management and Enterprise Integration. We had to combine multiple technologies and services to provide useful business solutions.

With the release of WSO2 API Manager 4.0, we no longer have to combine multiple technologies and platforms and WSO2 API Manager 4.0.0 is a complete platform for building, integrating, and exposing digital services as managed APIs in the cloud, on-premise, and hybrid architectures.

Download the latest version of WSO2 API Manager today, and follow the product documentation to evaluate/ explore the capabilities of it.



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