Uldar is a tiny library that can be used to extend any custom application to bring CMS functionality
Uldar CMS is a tiny Scala library which values providing full JSON API on backend side, that can be easily extended using a number of plugins from extension collection or implementing custom ones.
It does not depend on specific database, backend or fronend framework, so you free to use the one that fits you best
Most of extensions come with samples covering all popular databases (MySQL, PostgreSQL) and frontend libraries such as AngularJs, ReactJs, VueJs, etc so you have a choice and can find the one you need.
Providing user with a high level API to build the app using UI elements is a nice idea, but in the same time it does not scale enough when we come to business specific needs where general web components don't fit well.
Low level API can be used to build robust and neat logic but there is always a place to provide user with tools to change business specific information without touching the code.
We think good CMS engine should help developer to raise the API to UI tools, end users can use, without restricting the code base to follow CMS structure and eliminate the case when user totally end up with being embraced with CMS restrictions.
Uldar introduces two main abstractions Widget and ApiExtension, the application can be extended with either
A Widget is the smallest fundamental building block of UI. Although there is no direct way to manipulate widgets via UI (there is only program API),
they are still considered to be the option of extending an application.
Widget is recursive structure meaning it can consists of list of other widgets and so on.
Some samples of widgets:
- Block of news (configuration might look like: filtration by tags, subject, topic, views count, etc)
- Subscribe form (configuration might look like: plainId, text, coupon, etc)
- Show only block that has nested widgets but shown only for Subscribers/User roles (configuration: roleId, accessLevel, etc)
- Image carousel (configuration: filtration by tag, limit, ect)
- Popular goods (configuration: filtration by category, price, ect)
Widget is a notion of composition of logic on both frontend and backend
Widget is an abstract term assumed combination of WidgetDataProvider, WidgetRenderer and WidgetConfigurator
WidgetConfigurator is UI component implemented on frontend, that used by user to define and configure widget
WidgetDataProvider is backend service which provides data model to render the widget (using configuration), and process all widget API calls
WidgetRenderer is UI component which is in charge of rendering the widget using render data model on page
Using ApiExtension is a way to expand backend API with new functionality, there is no any specific restriction about its implementation
Extension is a reusable collection of functionality that can be shared and reused by others.
Extension can bring set of ApiExtension and WidgetDataProvider implementations.
You can find most popular extensions on official page
Feel free to implement your own extension following the developers guide
You can't use an Uldar CMS as it is, because it is just a library.
Though integration is quite straightforward, you need to bind ExtensionService.processApiCall to HTTP call (say using /uldar/* url)
There are some existing integration libraries you can use for PlayFramework, SpringMVC, http4s