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How to Build a Front-End Architecture in OutSystems

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  • This article provides you insights about how to build a front-end architecture in OutSystems, based in the OutSystems UI, and shows examples and use cases of how to evolve this architecture.

    Simple Project Architecture

    This section explains the structure of the architecture of a simple project.

    Simple Project Architecture

    The OutSystems UI is the base application. Based on this, we build the Project Theme (you can add other Project Patterns based on the OutSystems patterns only) and finally the Project Application. The Project style guide is also based on the project theme. The Template Project is the template for your application.

    Patterns in Front-End Architecture

    The following graphic shows how to structure the Front-end architecture at OutSystems UI.

    Patterns in Front-End Architecture

    The OutSystems UI is the base application, containing all the UI patterns and screen templates ready to use.

    The red squares represent the OutSystems UI patterns. The yellow squares represent the changed styles that have the rules to customize your Corporate Styles. These are based on the OutSystems UI. The yellow triangles represent new Corporate Styles patterns. These square and triangle patterns defined at Corporate Styles are used in all your applications and can be changed at specific Themes. For example, the Apps theme on the left side has a new circle pattern, the Internal Apps theme has a new pentagon pattern, and the Partners Apps theme has a new diamond pattern.

    You can have several applications based on these themes. At the current example, you have external apps that share the same properties defined in the Apps theme, internal apps that share the same Internal Apps theme, and partner apps that share the Partner Apps theme, all these based on the Corporate Styles.

    Front-End Use Case Architecture

    The following diagram shows how to structure your Front-End architecture:

    Front-End Use Case Architecture

    Based on the OutSystems UI, you can set your institution branding and broad style definitions. These contain the common patterns and widgets, based on a Core Stylesheet. The OutSystems UI contains evolved code optimized with the last best practices, usable in a large range of tested devices and browsers.

    Client Case Study

    The following diagram shows an example of an architecture for a company that built a B2C custom application for a partner with an OutSystems UI-based theme, and wants to grow and build more B2C applications, and create also B2B and Corporate applications with different themes.

    Existing B2C Flow → Business to Consumer (for example, a security agency website) New B2B Flow → Business to Business (for example, security agency website only for partners) New Corporate Flow → (for example, security agency intranet applications)

    Front-End Use Case Architecture

    Based on the OutSystems UI, this company built two different themes: one for B2C applications, and other for corporate applications. They built a Partner Theme with specific styles and layouts and used it to create a Custom Theme Style Guide for a partner, where all branding of their partner (layouts, colors, fonts, and so on) is set. They built a custom application for a final customer, using the styles and themes defined in this style guide. On the other hand, they built a different Corporate Theme that defines their company’s styles and layouts and a Store Theme Style guide specific for their store.

    The company now wants to build applications for its customers, using a particular style guide for this kind of application: the B2C Theme 1. This style guide defines all the styles and layouts to use for every B2C App they build (in this example: B2C App 1 and B2C App 2). They want to start developing B2B applications, for example, a website for their partners only, and for this, they need to build a specific B2B Theme and a B2B Style Guide, which defines all the styles and patterns to use in the new B2B Apps. Also, based on their existing Corporate Theme, they plan to build a Store App that uses the existing Store Theme style guide and create a new one for their internal corporate applications: the Corp Theme 2 style guide.

    Store Application Front-End Architecture

    The diagram below focus on the architecture of the store application of the previous example:

    Store App Front-End Architecture

    The new store application consumes patterns and templates that were previously defined at the Store Style Guide, and also the corporate patterns and resources define at the Corporate Base Style.

    Partner Application Front-End Architecture

    The diagram below focus on the architecture of the partner application of the previous example:

    Partner App Front-End Architecture

    The partner’s B2C applications consume custom resources, the B2C Style Guides, partner patterns and resources defined at the Partner Base, and B2C patterns and resources defined at the B2C Base style.