Glossary of Revolution Terms

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ACL¶

An ACL, or Access Control List, is a set of Permissions attached to an object. More background is on Wikipedia. See more

Add-on¶

A MODX Third-party Component (3PC) that does not modify the Core or extend its classes, but still adds functionality to the site.

Asset¶

Any file under the assets path defined by MODX_ASSETS_PATH (usually /assets): libraries, images, CSS, JavaScript, class files, Extra packages, and similar.

Authentication¶

How MODX confirms a User identity for Manager or front-end login. Core auth can be extended with custom authentication classes. See more

Back-end¶

A synonym for the MODX Manager.

Cache, caching¶

Stored copies of data MODX reuses so it can skip repeated database work. Revolution caches at several levels. See more

Category¶

An optional label you attach to an Element, Property Set, or related objects so you can group them in the Manager.

Child Resource¶

A Resource that sits under a Parent Resource (often a Container) in the Resource Tree.

Chunk¶

Reusable HTML (or other markup) stored as an Element. You insert a Chunk with a Chunk Tag. See more

Chunk Tags¶

Tags in the form [[$ChunkName]] that insert a Chunk.

Component¶

Also called a Third-party Component or 3PC. Extra code that extends MODX, often as an Add-on, Extension, or template package.

Connector¶

Entry point for AJAX requests in MODX. A Connector loads the MODX class, sanitizes request data, then hands the request to a Processor. See more

Container¶

A Resource marked so it can hold Child Resources in the Resource Tree. Containers are Parent Resources when they have children.

Content Type¶

Sets the file extension, MIME type, and binary flag for a Resource. See more

Context¶

A boundary for Resources and settings. Sites use Contexts for subdomains, languages, and similar splits.

Context Setting¶

A setting scoped to one Context. It can create a new key or override a System Setting.

Controller¶

Manager PHP class that builds a Manager page (loads assets, sets placeholders, returns the view). Custom Manager Pages use Controllers. See more

HTTP cookie data the browser stores for the site. MODX uses cookies with the Session for login and request state.

Core Workspace¶

Named record of a MODX Core installation path in the database. The setup process creates the default workspace for the Core you install. Multi-workspace switching from the Manager is not a shipped day-to-day workflow in current Revolution releases.

Database¶

The SQL database (MySQL/MariaDB) that stores MODX objects: Resources, Elements, Users, settings, and more. Revolution talks to it through xPDO.

Document¶

A Resource type for a normal website page.

Document Identifier¶

See Resource Identifier.

Element¶

Also called a Content Element: a Template, Template Variable, Chunk, Snippet, Plugin, Category, or Property Set in the Manager Elements tree.

Error log¶

The Manager/system log where MODX writes PHP and application errors. You open it from Reports → Error Log. Path and filename follow the error_log_filepath and error_log_filename System Settings.

Extension¶

Also called a Core Extension. A Third-party Component that changes Core behavior, such as a custom User or authentication class, a cache provider, or Context-related classes.

File Manager¶

See Media Browser.

File Resolver¶

An xPDOVehicle Resolver that copies files from a Transport Package source path to a target path on the site.

File System¶

Local disk storage for site files. The default Media Source type reads and writes the File System. See more

Form Customization¶

Manager feature where you define Rules that change how Manager forms look and behave. See more

Form Customization Set¶

Also called an FC Set. A group of Form Customization Rules for one Manager page (action). See more

Friendly URLs, Friendly aliases¶

SEO-friendly URLs (often shortened to FURLs in MODX). With Friendly URLs enabled, MODX builds readable paths from Resource aliases instead of raw request IDs. See more

FURLs¶

See Friendly URLs, Friendly aliases.

Hooks¶

In FormIt and similar Extras, a Hook is PHP that runs after (or, as a Prehook, before) form handling: email, redirect, spam checks, custom logic. See more

Installer¶

See Package Management.

Language Tags¶

Tags in the form [[%LanguageStringKey]] that pull strings from the Lexicon.

Lexicon¶

Dictionary of strings keyed by culture (more specific than a bare language code, for example en) used to localize the Manager and Extras. Lexicon entries replace older flat language files and you can edit many of them in the Manager.

Lexicon Management¶

Manager tools for browsing and editing Lexicon entries by namespace and Lexicon Topic. Related developer docs live under Internationalization.

Lexicon Topic (formerly Foci)¶

A group of Lexicon entries for one subject. Revolution loads topics on demand to keep Manager pages lighter.

Link Tags¶

Tags in the form [[~ResourceId]] that output the URL of a Resource.

Manager¶

The back-end administration UI for MODX (also called the Back-end).

Media Browser¶

Also called the MODX Browser or File Manager. Manager UI for browsing and picking files through a Media Source (upload, folders, insert into Resources and TVs).

Media Source¶

Defines where media lives: local File System, Amazon S3, or other drivers. Core ships File System and S3. More drivers come from Package Management or custom code. See more

Manager navigation items (main menu, user menu, and similar). Packages and Core register menu entries that Controllers open.

MIME type¶

Internet Media Type for a file or response (for example text/html). A Content Type stores the MIME type for Resources of that type.

MODX Browser¶

See Media Browser.

Namespace¶

Label Components use to group Lexicon entries, settings, and related objects. A Namespace also points at the absolute path where the Component lives.

Object¶

In xPDO terms, a PHP object mapped to a database row (for example a Resource or User record). See also Primary key.

Package Management¶

Manager UI and service for installing Transport Packages (Extras) from remote providers or uploaded packages. Also called the Extras Installer. See more

Parent Resource¶

A Resource that has Child Resources under it in the Resource Tree. When the parent is marked as a container, it is also a Container.

Placeholder Tags¶

Tags in the form [[+PlaceholderName]] for values set in PHP, usually with $modx->setPlaceholder('placeholderName', 'value') in a Snippet or Plugin.

Plugin¶

PHP Element that runs on System Events (save a Chunk, clear the cache, and so on), unlike a Snippet that you call from content. See more

Prehooks¶

Hooks that run before the main FormIt (or similar) processing. See Hooks.

Primary key¶

Database column (or columns) that uniquely identify a row. For Resources the primary key is the Resource ID shown in the Resource Tree.

Processor¶

PHP script that performs one Manager or Connector action (create, update, get list, and so on). Connectors route AJAX calls to Processors. See more

Property¶

One named parameter on an Element (default value for a Snippet property, Chunk property, and similar).

Property Set¶

A named collection of Properties you attach to an Element so callers can override defaults for a specific use.

Renderer¶

Code that changes how a value appears in a Manager grid or similar UI. Collections and other Extras define custom renderers. See more

Request alias parameter¶

System Setting request_param_alias: query parameter name MODX uses for the Resource alias when Friendly URLs are off or as a fallback. Default is q. See more

Request ID parameter¶

System Setting request_param_id: query parameter name for the Resource ID. Default is id. See more

Resolver (from Transport Package)¶

Script or built-in action that runs after a Transport Vehicle is installed or uninstalled. Resolvers run after the vehicle object is saved.

Example PHP Resolver: attach Plugin events to a newly installed Plugin.

Example File Resolver: copy assets/getResources from the vehicle path into the site assets directory.

Resource¶

Parsed unit of site content. Common subtypes: Document, Weblink, Symlink, Static Resource. See more

Resource Field¶

A column on the Resource (site_content) row such as pagetitle, longtitle, introtext, alias, or menuindex. Many appear on the Resource edit screen and through Resource Tags.

Resource Identifier¶

Also called Document ID, Resource ID, or Document Identifier: the number in parentheses in the Manager Resource Tree that uniquely identifies the Resource.

Resource Tags¶

Tags in the form [[*fieldOrTvName]] for Resource Fields or Template Variables.

Resource Tree¶

Hierarchical list of Resources in the Manager (usually the left tree). Parent/child placement shapes site structure and URLs.

Session¶

Server-side period that ties a visitor’s requests together (login state, flash data, and related values), usually backed by a Cookie.

Setting Tags¶

Tags in the form [[++SettingName]] for System Settings, Context Settings, and User Settings.

Snippet¶

PHP Element you call from Templates, Chunks, or Resources to run dynamic code. See more

Snippet Tags¶

Tags in the form [[SnippetName]] that call a Snippet.

Static Element¶

An Element whose source lives in a file on disk instead of only in the database. See more

Static Resource¶

Resource type that points at a file on the site. MODX serves that file’s contents as the Resource content.

Symlink¶

Resource type that points at another local Resource and shows that Resource’s content.

System Event¶

Named point in Core or Extra code where Plugins can run (save, remove, cache clear, and many others). See more

System Setting¶

Site-wide configuration key. Context Settings and User Settings can override it.

Template¶

Element that defines the outer markup for Documents of a given type. Resources select a Template. The Template holds Chunk, Snippet, and TV tags. See more

Template Variables (or TVs)¶

Custom fields on a Resource, created by the site builder and edited on the Resource screen. Output them with Resource Tags. See more

Transport Package¶

Zipped set of Transport Vehicles you install through Package Management or distribute between sites. See more

Transport Vehicles¶

Package units inside a Transport Package. Each vehicle carries objects or files and install rules. See more

TV¶

See Template Variables (or TVs).

URI¶

Path (and related identifiers) MODX associates with a Resource for routing and Friendly URLs. Related Resource fields include uri and alias.

User¶

Manager or front-end account: username, credentials, profile, and group membership. See more

User Group¶

Named set of Users used with Access Policies and permissions. See more

User Setting¶

Setting for one User. It can add a key or override matching Context and System Settings.

User's Primary Group¶

The main User Group assigned to a User. Policies and defaults often key off the primary group.

Username¶

Validator (from Transport Package)¶

Script or built-in check that runs before a Transport Vehicle installs or uninstalls. true continues the action. false aborts it.

Validators often check writable directories, required Elements, or MySQL/PHP versions.

Weblink¶

Resource type that points at an external URL or another Resource and redirects visitors there. The Weblink target is that destination URL or Resource. System Setting use_weblink_target controls whether link tags and makeUrl() print the target URL directly or the Weblink’s own MODX URL.

xPDOVehicle¶

Base Transport Vehicle class. It stores xPDOObject instances (table rows) plus attributes that control install and uninstall, including Validators and Resolvers.