Skip to main content

Query for Component Presentations

Use LimitFilter, SortParameter, CPAssembler, CPFactory

The following sample queries the Content Delivery database for Components in a given Publication by using the PublicationCriteria and ItemTypeCriteria.

It also uses a ResultFilter in the form of a LimitFilter and a SortParameter to only retrieve a maximum set of Components in the given sort order (descending according to their last-publish-date).

For each of the identified Components (if any), we retrieve the Dynamic Component Presentation using the CT with the highest priority. Finally, we feed these DCPs into the ComponentPresentationAssembler in order to retrieve their actual content.

<%
    JSPPage jspPage = new JSPPage(pageContext, "tcm:83-3246-64");
    cpAssembler = new ComponentPresentationAssembler(jspPage);
    Query query = new Query();

    PublicationCriteria publicationCriteria = new PublicationCriteria(83);
    ItemTypeCriteria itemTypeCriteria = new ItemTypeCriteria(ItemTypes.COMPONENT);
    AndCriteria andCriteria = new AndCriteria(publicationCriteria, itemTypeCriteria);
    query.setCriteria(andCriteria);

    ResultFilter resultFilter = new LimitFilter(2);
    query.setResultFilter(resultFilter);

    SortParameter sortParameter = new SortParameter(
        new ItemLastPublishColumn(), SortDirection.DESCENDING);
    query.addSorting(sortParameter);

    String[] items = query.executeQuery();
    out.println("<p><b>Publication=83 AND ItemType=16 Query: </b>" + list(items) + "</p>");
    out.println("<p><b>DCPs:</b>");
    writeCP(out, items);
    out.println("</p>");
%>

<%!ComponentPresentationAssembler cpAssembler = null;

public String list(String[] items) {
    StringBuilder sb = new StringBuilder();
    for (String item : items) {
        sb.append(item + " ");
    }

    return sb.toString();
}

public void writeCP(JspWriter out, String[] items) throws IOException {
    try {
        if (items == null || items.length == 0) {
            return;
        }

        TCMURI itemUri = new TCMURI(items[0]);
        ComponentPresentationFactory cpFactory = new ComponentPresentationFactory(
            itemUri.getPublicationId());

        for (String compUri : items) {
            ComponentPresentation cp = cpFactory
                .getComponentPresentationWithHighestPriority(compUri);
            if (cp == null) {
                out.println("Found null CP for compUri=" + compUri + "<hr/>");
            } else {
                out.println(cpAssembler.getContent(cp.getComponentId(),
                    cp.getComponentTemplateId()) + "<hr/>");
            }
        }
    } catch (ParseException pe) {
        out.println("ParseException occurred: " + pe);
    }
}%>


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...

Toolkit - Performance

This post if part of a series about the File System Toolkit  - a custom content delivery API for SDL Tridion. This post presents performance data that was captured for each major functionality with and without caching Linking, CP Assembler, Component Presentation Factory, Dynamic Content Queries, Model Factory. The data was captured on a 2014 Macbook Pro 15", 16 GB RAM, 2.6 GHz Intel Core i7 running OS X El Capitan. Test methodology: each test was run for 3 minutes and the total number of successful Toolkit API calls was measured. Then the number of calls per second was computed 'with cache' and 'without cache' test runs. Then a cache boost factor was calculated by diving (the number of API calls with cache) / (number of API calls without cache). Each cache test was executed 3 times, with different cache time-to-live values of 1 second, 5 seconds and 0 seconds (eternal cache, no expiration). The rationale is to see what impact different cache expiration/evi...

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...