Skip to main content

Resolve CSS Images in Output TBB

This week's TBB is Resolve CSS Images in Output TBB. This template identifies unresolved image references inside CSS selectors "background: url('tcm:x-yy')", publishes the MMC and replaces the reference with the resolved URL.

I got this TBB from my colleague Eric Huiza, so he gets the credit for it ;)

Name
Render Css Images In Output TBB
Type
·    Template in .NET Assembly
Description
Used to:
·    Resolve references to Multimedia Components TcmUris inside CSS syntax;
·    Publish the MMC and replace the TcmUri reference with the resolved URL;
Notes:
This generic TBB uses the Output item to search for references to MMC TcmUris (or WebDav URLs) inside 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

The Code

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

    private const string CSS_IMG_REG_EX = @"background(-image)?:(\s)*(transparent)?(\s)*(url[\s]*\([\s]*(?<url>[^\)]*)[\s]*\)[\s]*)+";
    private readonly Regex cssImgRegEx = new Regex(CSS_IMG_REG_EX, RegexOptions.IgnoreCase);

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

        foreach (Match match in GetBackgroundEntities(css)) {
            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);
                css = css.Replace(uri, binary.Url);
            }
        }

        outputItem.SetAsString(css);
    }

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


Comments

Popular posts from this blog

Running sp_updatestats on AWS RDS database

Part of the maintenance tasks that I perform on a MSSQL Content Manager database is to run stored procedure sp_updatestats . exec sp_updatestats However, that is not supported on an AWS RDS instance. The error message below indicates that only the sa  account can perform this: Msg 15247 , Level 16 , State 1 , Procedure sp_updatestats, Line 15 [Batch Start Line 0 ] User does not have permission to perform this action. Instead there are several posts that suggest using UPDATE STATISTICS instead: https://dba.stackexchange.com/questions/145982/sp-updatestats-vs-update-statistics I stumbled upon the following post from 2008 (!!!), https://social.msdn.microsoft.com/Forums/sqlserver/en-US/186e3db0-fe37-4c31-b017-8e7c24d19697/spupdatestats-fails-to-run-with-permission-error-under-dbopriveleged-user , which describes a way to wrap the call to sp_updatestats and execute it under a different user: create procedure dbo.sp_updstats with execute as 'dbo' as

I Have Gone Dark

Maybe it's the Holidays, but my mood has gone pretty dark. That is, regarding the look and feel of my computer and Tridion CME, of course. What I did was to dim the lights on the operating system, so I installed Placebo themes for Windows 7 . I went for the Ashtray look -- great name :) My VM looks now like this: But, once you change the theme on Windows, you should 'match' the theme of your applications. Some skin easily, some not. The Office suite has an in-built scheme, which can be set to Black , but it doesn't actually dim the ribbon tool bars -- it looks quite weird. Yahoo Messenger is skinnable, but you can't change the big white panels where you actually 'chat'. Skype is not skinnable at all. For Chrome, there are plenty of grey themes. Now i'm using Pro Grey . But then I got into changing the theme of websites. While very few offer skinnable interfaces (as GMail does), I had to find a way to darken the websites... Enter Stylish -- a pl

REL Standard Tag Library

The RSTL is a library of REL tags providing standard functionality such as iterating collections, conditionals, imports, assignments, XML XSLT transformations, formatting dates, etc. RSTL distributable is available on my Google Code page under  REL Standard Tag Library . Always use the latest JAR . This post describes each RSTL tag in the library explaining its functionality, attributes and providing examples. For understanding the way expressions are evaluated, please read my post about the  Expression Language used by REL Standard Tag Library . <c:choose> / <c:when> / <c:otherwise> Syntax:     <c:choose>         <c:when test="expr1">             Do something         </c:when>         <c:when test="expr2">             Do something else         </c:when>         <c:otherwise>             Do something otherwise         </c:otherwise>     </c:choose> Att