Objects and nodes
The structure of a site is a tree. The book's example tree holds a document branch, ordered galleries and a forum. The key idea of this chapter is a distinction that is easy to miss and important to keep:
- A content object is the information itself: its attributes, versions and translations. It has one object ID.
- A node is a placement of an object in the tree. It has a node ID, a parent node and a place in the order.
One object can have more than one node, that is, appear in several places, without being copied. Delete one placement and the object stays where it is still placed. The name belongs to the object, and is shared by the versions of one translation. In the administration, the places of an object are its locations (the Locations part of an item in Content structure), and one of them is the main location: the one whose address is the object's own.
The address of a node on the site comes from its names along the path (see Links, URL aliases and
wildcards); /content/view/full/<node id> is the plain form and always works.
Sections
A section is a virtual collection of nodes that belong together by meaning or by function. Sections do two jobs:
- Permissions. A role can be limited to a section ("editors may edit articles in the News section").
- Presentation. A template can look at the section and show a different menu or even a different page layout for it.
Rules the book states and that still hold:
- A node belongs to one section.
- A new child node inherits the section of its parent, so assigning a section to the top of a branch sets it for what is created below it later. (What already exists below needs Assign content on the section's page, which gives the section to the chosen item and everything below it.)
- There is always at least one section, the default one.
How to create and assign sections, and what the section also controls, is in Sections and Sections, roles and access for builders.
Try it
- Open Content structure and note the tree on the left.
- Open any item and look at its Locations: the main location, and any other.
- Add a second location for an item (the Locations window of its edit form) and see the same item appear in two branches. Change the title in one place, and both show it.
Next: classes, attributes and objects.
Source and license
Adapted from chapter 2, "Content Management with eZ publish", of Learning eZ publish: Building Content Management Solutions by Paul Borgermans, Tony Wood, Paul Forsyth, Martin Bauer, Björn Dieding and Ben Pirt (additional material by Bruce Morrison), second edition, 2024, Book-Learning-eZPublish. Copyright (c) 2004-2024 7x and Graham Brookins. Licensed under the GNU Free Documentation License, version 1.3 or any later version, with no Invariant Sections, no Front-Cover Texts and no Back-Cover Texts (the license). Changes: rearranged and shortened; settings, labels, datatypes, tags and URLs checked against Exponential 6 and corrected; links to the current guides added.