Tales from the Evil Empire

Placement files describe how to dispatch shapes into zones. They are necessary in order to decouple UI composition from individual templates. Templates can focus on what to render, while placement determine what to render where. In yesterday’s post, I’ve shown one rudimentary example of placement. There can be a placement file at the root of each module and theme. A placement file can either be a placement.json file, or aplacement.js file if the format for JSON placement files is not sufficiently flexible for the problem at hand.

Placement works in a relative manner: more than one content item can appear on any given page, for example through lists of content items, or as widgets. Placement can dispatch the shapes created by the parts of a content item into the local zones under a given root shape that is usually the main shape for the content item.

A content part is a reusable piece of content that can be composed with other parts into a content type. For example, a blog post content type could be built by composing a title part, a text part for the post's body, a tags part, and a list of comments. DecentCMS comes with a few parts built-in, such as title and text, but it's easy to write your own.

Creating your own content type can be done by adding it to the configuration of the "content" feature in the site's settings.jsonfile. You may also alter an existing content type and add new parts to it.

In this post, I'll use the example of a rudimentary tags part. The part will expose a list of tags, which are simple strings.

In previous posts, I’ve shown the structure of a DecentCMS module, and how to describe such a module through its manifest. In this post, I’ll go into the meat of the matter by showing how to write an actual service. DecentCMS services are just classes that fulfill a specific named contract. Services can consume other services, using existing or new contracts, thus providing a generic mechanism for extensibility, where extensions to core services can expose their own extensibility points.

In the previous post, I showed the basic structure of a DecentCMS module. In this post, I’ll start digging into the details by showing how a module can declare metadata about itself. The package.json file, also called "module manifest", is where DecentCMS module authors can declare what their module consists of. It is a standard NPM manifest file, with a few additional properties that DecentCMS understands.

Modules are made of all the files under a subdirectory of the /modules directory. A module may be put directly under the/modulesdirectory, or it can be part of a "module area".

Module areas are groups of modules that have a common origin, and make sense being together. An example of a module area is the "core" area, that groups all the core modules that come standard with DecentCMS. They provide essential features that are likely to be useful to any DecentCMS web site. Another advantage of module areas is that they make it easier to manage a whole group of modules under a single Git repository.

Module areas are simply subdirectories of the /modules directory that do not have a package.json file directly under it, but has one or more modules under it. You may not put areas under areas.

The navigation files that can be found in a site's "navigation" directory describe the menus that are available to the system. The default.json file in particular describes the default menu for the site. By editing this file, you can modify the menu's hierarchical structure and its contents.

See if you can figure that one out in less than ten seconds, in which case kudos to you… What does this code return?

['1', '2'].map(parseInt)

After an IE6-induced era of stagnation, the Web has adopted a steady pace of serious innovation and progress these last few years. Regular browser updates, collaboration on open standards, and some polyfill libraries make the Web a much more viable development platform than it used to be. Or does it? An exploration of the caniuse.com site paints a more depressing picture: Internet Explorer 8 is dragging us all behind with its market share of up to 20% (depending where you get your statistics). 20%! Are you going to leave 20% of your users behind? Should you still care that much? I’ll be arguing in this post that you shouldn’t, in many situations.