Skip to main content

Resolve JS Images In Output TBB

Image
By
The TBB of this week is Resolve JS Images In Output, originally written by my colleague Eric Huiza. Basically, the TBB does what the name says. It looks for certain images in the Output item and publishes them.

The images have to be in TcmUri or WebDAV format and they must appear in the url('path') format. This is the format that a CSS background selector uses, for example, only that it appears in JavaScript.

The TB transforms something like:

document.getElementById(openingTitleId).style.background=
    "url('/webdav/Content/Building Blocks/Assets/images/titlebar.gif') no-repeat";

into this:

document.getElementById(openingTitleId).style.background=
    "url('/assets/images/titlebar_tcm1-2.gif') no-repeat";

Description

Name
Resolve JS Images In Output TBB
Type
·    Template in .NET Assembly
Description
Used to:
·    Resolve references to Multimedia Components TcmUris or WebDAV URLs inside JS syntax;
·    Publishe the MMC and replaces the TcmUri/WebDAV reference with the resolved URL;
Notes:
This generic TBB uses the Output item to search for references to MMC TcmUris (or WebDav URLs) inside JavaScript references to CSS ‘background’ selectors.
If such MMC TcmUri is identified, the MMC is published (to the mapped Structure Group) and the returned URL replaces the TcmUri reference.
The Output item is rewritten with the resolved URLs.
Parameters
n/a
Applicable to
Any template where an Item called ‘Output’ exists in the Package

Code

[TcmTemplateTitle("Resolve JS Images In Output TBB")]
public class ResolveJsImagesInOutput : ITemplate {

    public const string JS_IMG_REG_EX = @"(url[\s]*\([\s]*(?<url>[^\)]*)[\s]*\))+";
    public readonly Regex cssBgRegEx = new Regex(JS_IMG_REG_EX, RegexOptions.IgnoreCase);

    public void Transform(Engine engine, Package package) {
        GenericUtils utils = new GenericUtils();
        Item outputItem = package.GetByName(Package.OutputName);
        string js = outputItem.GetAsString();

        foreach (Match match in GetUrlEntities(js)) {
            string uri = match.Groups["url"].Value.Replace("\"", string.Empty).Replace("'", string.Empty);
            string localUri = utils.LocalizeUri(engine, uri);
            Component imgComponent = engine.GetObject(localUri) as Component;
            if (imgComponent != null) {
                Binary binary = utils.PublishBinary(engine, package, imgComponent);
                js = js.Replace(uri, binary.Url);
            }
        }

        outputItem.SetAsString(js);
    }

    private IEnumerable<Match> GetUrlEntities(string js) {
        return cssBgRegEx.Matches(js).Cast<Match>().
            Where(w => w.Groups["url"].Value.StartsWith("\"/webdav") ||
                w.Groups["url"].Value.StartsWith("'/webdav") ||
                w.Groups["url"].Value.StartsWith("\"tcm:") ||
                w.Groups["url"].Value.StartsWith("'tcm:"));
    }
}

where the util.LocalizeUri method is the following:

public string LocalizeUri(Engine engine, string tcmUri) {
    if (TcmUri.IsValid(tcmUri)) {
        return engine.LocalizeUri(new TcmUri(tcmUri));
    } else {
        return tcmUri;
    }
}


Labels:

Comments

Post a Comment

Popular posts from this blog

A DD4T.net Implementation - Custom Binary Publisher

By
The default way to publish binaries in DD4T is implemented in class DD4T.Templates.Base.Utils.BinaryPublisher and uses method RenderedItem.AddBinary(Component) . This produces binaries that have their TCM URI as suffix in their filename. In my recent project, we had a requirement that binary file names should be clean (without the TCM URI suffix). Therefore, it was time to modify the way DD4T was publishing binaries. The method in charge with publishing binaries is called PublishItem and is defined in class BinaryPublisher . I therefore extended the BinaryPublisher and overrode method PublishItem. public class CustomBinaryPublisher : BinaryPublisher { private Template currentTemplate; private TcmUri structureGroupUri; In its simplest form, method PublishItem just takes the item and passes it to the AddBinary. In order to accomplish the requirement, we must specify a filename while publishing. This is the file name part of the binary path of Component.BinaryConten
1 comment
Read more

Toolkit - Dynamic Content Queries

By
This post if part of a series about the  File System Toolkit  - a custom content delivery API for SDL Tridion. This post presents the Dynamic Content Query capability. The requirements for the Toolkit API are that it should be able to provide CustomMeta queries, pagination, and sorting -- all on the file system, without the use third party tools (database, search engines, indexers, etc). Therefore I had to implement a simple database engine and indexer -- which is described in more detail in post Writing My Own Database Engine . The querying logic does not make use of cache. This means the query logic is executed every time. When models are requested, the models are however retrieved using the ModelFactory and those are cached. Query Class This is the main class for dynamic content queries. It is the entry point into the execution logic of a query. The class takes as parameter a Criterion (presented below) which triggers the execution of query in all sub-criteria of a Criterio
Post a Comment
Read more

Event System to Create Mapped Structure Groups for Binary Publish

By Unknown
As a continuation of last week's Publish Binaries to Mapped Structure Group , this week's TBB is in fact the Event System part of that solution. Make sure you do check out the previous post first, which explains why and what this Event System does. To reiterate, the Event System intercepts a Multimedia Component save, take its Folder path and create a 1-to-1 mapping of Structure Groups. The original code was written, again, by my colleague Eric Huiza : [ TcmExtension ( "MyEvents" )] public class EventsManager  : TcmExtension {     private Configuration configuration;     private readonly Regex SAFE_DIRNAME_REGEX = new Regex ( @"[\W_]+" );     public EventsManager() {         ExeConfigurationFileMap fileMap = new ExeConfigurationFileMap ();         fileMap.ExeConfigFilename = Path .GetDirectoryName( Assembly .GetExecutingAssembly().Location) + "\\EventSystem.config" ;         configuration = ConfigurationManager
Post a Comment
Read more