Skip to main content

TBB of the Week - Render Page Text Block

By Unknown
I thought about starting a new section on my blog -- TBB of the Week. The intention is to publish a new TBB every week that is somehow worthy. Maybe it is a very generic one, or a best practice, or even a bad practice. There should be a description of the TBB, what it does, where/how to use it in a Compound Template. Of course, there will be source code too.

So to start with, the first "TBB of the Week" is going to be Render Page Text Block TBB. I first got this TBB from a colleague of mine, Eric Huiza, so I won't take credit for it.

Name
Render Page Text Block TBB
Type
· Template in .NET Assembly
Description
Used to:
· Publish Text Block scripts (JS or CSS) attached to a Page as metadata;
Notes:
This TBB expects the Page to have metadata field ‘script’ that contains a Component Link to the Text Block Component. The TBB creates an Output item (or overwrites the existing one) with the content of the TextBlock field in the linked Text Block Component.
The Page in this case should not contain any Component Presentations.
Parameters
n/a
Applicable to
Page Templates

I like the idea a lot -- you don't have to create Component Presentations on your Page in order to publish 'static' text assets like JavaScript or CSS. Instead you just attach them to your Page Metadata.

One thing I don't like, is the inability to use the "Where Used" publishing. Namely, if you want to publish the JS/CSS Text Block Component, this setup will not allow that. In a normal situation, where the Component appears on the Page as CP, publishing the Component will publish the Page using it. Not in this case...

The Code

[TcmTemplateTitle("Render Page Text Block TBB")]
public class RenderPageTextBlock : ITemplate {

    public void Transform(Engine engine, Package package) {
        Item pageItem = package.GetByName(Package.PageName);
        Page page = engine.GetObject(pageItem) as Page;

        ItemFields metaFields = new ItemFields(page.Metadata, page.MetadataSchema);
        ComponentLinkField textblockField = metaFields.Where(w => w.Name.Equals("script")).Cast<ComponentLinkField>().ElementAtOrDefault(0);

        if (textblockField != null) {
            Component textblock = textblockField.Value;
            ItemFields itemFields = new ItemFields(textblock.Content, textblock.Schema);

            MultiLineTextField textField = itemFields.Where(w => w.Name.Equals("TextBlock")).Cast<MultiLineTextField>().ElementAt(0);

            Item output = package.GetByName(Package.OutputName);
            if (output == null) {
                package.PushItem(Package.OutputName, package.CreateStringItem(ContentType.Text, textField.Value));
            } else {
                output.SetAsString(textField.Value);
            }
        }
    }
}


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

Scaling Policies

By
This post is part of a bigger topic Autoscaling Publishers in AWS . In a previous post we talked about the Auto Scaling Groups , but we didn't go into details on the Scaling Policies. This is the purpose of this blog post. As defined earlier, the Scaling Policies define the rules according to which the group size is increased or decreased. These rules are based on instance metrics (e.g. CPU), CloudWatch custom metrics, or even CloudWatch alarms and their states and values. We defined a Scaling Policy with Steps, called 'increase_group_size', which is triggered first by the CloudWatch Alarm 'Publish_Alarm' defined earlier. Also depending on the size of the monitored CloudWatch custom metric 'Waiting for Publish', the Scaling Policy with Steps can add a difference number of instances to the group. The scaling policy sets the number of instances in group to 1 if there are between 1000 and 2000 items Waiting for Publish in the queue. It also sets the
Post a Comment
Read more