OpenLegacy Project Types

Owned by Rea Ben Yossef (Unlicensed)
Last updated: Jun 04, 2020
2 min read

In this section, we will try to answer the question "what project types can be created in OpenLegacy?".

This question is sometimes hard to answer because, using the OpenLegacy IDE, it is possible to create various kinds of projects, and even the meaning of the words "project type" can be confusing.

When "project type" refers to technologies on which the project is built, we can say that all OpenLegacy projects are first a Java project or, more specifically, a Maven + Spring project.
However, "project type" can also refer to the solution being built by the project, e.g., the solution can be a REST API, a SOAP web service, a Web application or a Java API. In these cases, we will refer to the front-end type of the project. 
Sometimes when working on an integration project, the "project type" can also refer to the back-end with which the project is integrating, so, for example, if we are referring to an integration project that is meant to integrate with a mainframe RPC, we can refer to a mainframe project type.

The OpenLegacy platform supports multiple project types, based on the type of legacy system, in two major categories:

  • SDK projects - which create a Java API from a single backend 

  • API/Microservices projects  - which integrate multiple Java APIs from previously created SDK projects

  • Web/Mobile projects - which create web  Angular-based components from the legacy backend entities and services, and enable web access

  • Project Templates - which create template for use in creating later projects to maintain standardization and ease workloads

SDK projects that expose legacy functionality as a Java SDK, and Microservices projects, that combine the Java SDKs (single or multiple) into a logical functional unit that is exposed externally.



OpenLegacy SDK Projects

All SDK projects comprise of one legacy back-end and produce one Java SDK.
The back-ends supported by the OpenLegacy IDE are listed below:

Legacy Back-Ends:

In the OpenLegacy IDE, back-ends are grouped by type: RPC and Screens.
Each group of legacy back-ends includes much common mechanism and architecture, but are differentiated by the connector used within each group.

For example, both mainframe screens and AS/400 screens include mappings of the navigation between the different screens, but each one will use different connector (TN5250j and TN3270).

  • RPC

    • Mainframe RPC

    • AS/400 RPC

    • SAP

    • SOAP Services

    • REST APIs

    • Stored Procedures

  • Screens

    • Mainframe Screens

    • AS/400 Screens

For the entire connectors list, click here



OpenLegacy Microservices Projects

Java SDK (API):

The Java SDKs created in the SDK Project workflow are used as the basic entities, or building blocks, in a conceptually larger project that orchestrates and exposes them externally. Therefore, an OpenLegacy Microservices project can integrate with more than one back-end, using multiple JAVA SDK projects, or a single backend, using a single SDK project as a new API that relies on pure Java, without any integration. Individual microservice projects can be loosely coupled between them, and all of the microservice projects (whether coupled or not), together with other units, comprise a single Microservice Architecture, or Ecosystem. Please refer to the https://openlegacy.atlassian.net/wiki/spaces/OV45/pages/656834561 page for a detailed understanding of this.

For further reading, see OpenLegacy API/Microservice Project.