@data-cache-styles : The Style Caching Performance Attribute

The data-cache-styles attribute is a performance optimization feature that caches style calculations for template-generated content. When enabled, Scryber reuses style computations across repeated template instances, dramatically reducing processing time and memory usage for large datasets.

On this page

Usage
- Basic Syntax
Supported Elements
Binding Values
Notes
Examples
See Also

Usage

The data-cache-styles attribute is applied to <template> elements, typically in conjunction with data-bind:

It enables style calculation caching for template iterations, providing:

Significant performance improvements for large collections (100+ items)
Reduced memory footprint during PDF generation
Faster rendering times by reusing computed styles
Consistent styling across all template instances

This attribute is essential for:

Processing large datasets (hundreds to thousands of items)
High-performance batch PDF generation
Reports with extensive repeated content
Memory-constrained environments
Time-sensitive document generation

Performance Impact: In testing with 1000+ items, enabling style caching can reduce generation time by 40-60% and memory usage by 30-50%.

<template data-bind="{{model.items}}"
          data-cache-styles="true"
          data-style-identifier="unique-cache-id">
    <!-- Content with consistent styling -->
    <div class="item">{{.name}}</div>
</template>

Basic Syntax

<!-- Enable style caching -->
<template data-bind="{{collection}}"
          data-cache-styles="true">
    <!-- Template content -->
</template>

<!-- Enable with explicit identifier -->
<template data-bind="{{collection}}"
          data-cache-styles="true"
          data-style-identifier="my-cache-key">
    <!-- Template content -->
</template>

<!-- Disable style caching (default) -->
<template data-bind="{{collection}}"
          data-cache-styles="false">
    <!-- Template content -->
</template>

Supported Elements

The data-cache-styles attribute is only supported on the following element:

<template> - The template element for repeating content

Note: This attribute only affects template iterations. It has no effect on non-template elements.

Binding Values

Attribute Values

Value	Description
`true`	Enable style caching for this template
`false`	Disable style caching (default behavior)

Type

Type: boolean Default: false

Expression Support

The attribute accepts literal boolean values or binding expressions:

<!-- Literal value -->
<template data-bind="{{items}}" data-cache-styles="true">

<!-- Bound value (enable for large datasets) -->
<template data-bind="{{items}}"
          data-cache-styles="{{count(items) > 100}}">

<!-- Bound from model property -->
<template data-bind="{{items}}"
          data-cache-styles="{{model.enableCaching}}">

Notes

How Style Caching Works

When data-cache-styles="true":

First Iteration: Scryber computes all styles for template content (CSS parsing, inheritance, specificity resolution)
Cache Storage: Computed styles are stored with the cache identifier
Subsequent Iterations: Scryber retrieves cached styles instead of recomputing
Memory Benefits: Only one set of style objects is maintained, referenced by all instances

Cache Identifier

The data-style-identifier attribute works with data-cache-styles:

<template data-bind="{{items}}"
          data-cache-styles="true"
          data-style-identifier="item-cache">

If not specified, Scryber generates an automatic identifier
Explicit identifiers enable cache sharing across multiple templates
Use unique identifiers for templates with different styling

When to Enable Style Caching

Enable style caching when:

Collection has 100+ items
Template content has consistent styling across iterations
Generating multiple similar documents
Performance or memory is a concern
Template uses complex CSS or class hierarchies

Don’t enable style caching when:

Collection has fewer than 50 items (minimal benefit)
Styles vary significantly between items (e.g., dynamic colors based on data)
Using inline styles with item-specific values
Template content structure changes per item

Style Variation and Caching

Style caching works best with static styles:

<!-- GOOD: Static styles, perfect for caching -->
<template data-bind="{{items}}" data-cache-styles="true">
    <div class="item-card">
        <h3>{{.name}}</h3>
        <p>{{.description}}</p>
    </div>
</template>

<!-- ACCEPTABLE: Dynamic content, static structure -->
<template data-bind="{{items}}" data-cache-styles="true">
    <div class="item" style="padding: 10pt;">
        {{.dynamicContent}}
    </div>
</template>

<!-- NOT IDEAL: Dynamic inline styles -->
<template data-bind="{{items}}" data-cache-styles="false">
    <div style="color: {{.color}}; background: {{.bgColor}};">
        {{.content}}
    </div>
</template>

Performance Guidelines

Small Collections (< 50 items):

Caching overhead may exceed benefits
Generally not recommended

Medium Collections (50-500 items):

Moderate performance improvement (20-30%)
Recommended if generation time is critical

Large Collections (500-1000 items):

Significant performance improvement (40-50%)
Highly recommended

Very Large Collections (1000+ items):

Dramatic performance improvement (50-60%+)
Essential for acceptable performance
Should be combined with pagination (data-bind-max)

Memory Considerations

Style caching reduces memory usage by:

Storing one copy of style objects instead of N copies
Reducing garbage collection pressure
Enabling larger batch processing

Combining with Other Optimizations

For maximum performance with large datasets:

<style>
    /* Use CSS classes instead of inline styles */
    .data-row { padding: 5pt; border-bottom: 1pt solid #ddd; }
</style>

<template data-bind="{{model.largeDataset}}"
          data-cache-styles="true"
          data-style-identifier="large-data"
          data-bind-max="100">
    <div class="data-row">
        {{.name}} - {{.value}}
    </div>
</template>

Optimizations combined:

CSS classes (reusable styles)
Style caching (avoid recomputation)
Pagination (limit items per generation)

Examples

1. Basic Style Caching

Enable caching for a simple list:

<template data-bind="{{model.items}}"
          data-cache-styles="true">
    <div style="padding: 10pt; border-bottom: 1pt solid #ddd;">
        {{.name}}
    </div>
</template>

2. Large Table with Caching

Optimize a large data table:

<table style="width: 100%;">
    <thead>
        <tr>
            <th>ID</th>
            <th>Name</th>
            <th>Status</th>
        </tr>
    </thead>
    <tbody>
        <template data-bind="{{model.records}}"
                  data-cache-styles="true"
                  data-style-identifier="table-rows">
            <tr>
                <td>{{.id}}</td>
                <td>{{.name}}</td>
                <td>{{.status}}</td>
            </tr>
        </template>
    </tbody>
</table>

3. Product Catalog with CSS Classes

Use CSS classes with caching for consistency:

<style>
    .product-card {
        padding: 15pt;
        margin-bottom: 10pt;
        border: 1pt solid #ddd;
        border-radius: 5pt;
    }
    .product-name {
        font-weight: bold;
        font-size: 12pt;
        color: #336699;
    }
    .product-price {
        color: #009900;
        font-size: 14pt;
    }
</style>

<template data-bind="{{model.products}}"
          data-cache-styles="true"
          data-style-identifier="product-list">
    <div class="product-card">
        <div class="product-name">{{.name}}</div>
        <p>{{.description}}</p>
        <div class="product-price">${{.price}}</div>
    </div>
</template>

4. Conditional Caching Based on Dataset Size

Enable caching only for large datasets:

<!-- Model: { items: [...], enableCache: items.length > 100 } -->
<template data-bind="{{model.items}}"
          data-cache-styles="{{count(model.items) > 100}}">
    <div style="padding: 8pt;">
        {{.name}}
    </div>
</template>

5. Multi-Template with Shared Cache

Share cache identifier across related templates:

<style>
    .list-item {
        padding: 10pt;
        border-bottom: 1pt solid #eee;
    }
</style>

<!-- First template -->
<h2>Active Items</h2>
<template data-bind="{{model.activeItems}}"
          data-cache-styles="true"
          data-style-identifier="item-style">
    <div class="list-item">{{.name}} - Active</div>
</template>

<!-- Second template with same cache -->
<h2>Inactive Items</h2>
<template data-bind="{{model.inactiveItems}}"
          data-cache-styles="true"
          data-style-identifier="item-style">
    <div class="list-item">{{.name}} - Inactive</div>
</template>

6. Invoice Line Items

Optimize repeating invoice lines:

<table style="width: 100%; border-collapse: collapse;">
    <thead>
        <tr style="background-color: #f0f0f0;">
            <th style="text-align: left;">Description</th>
            <th style="text-align: right;">Qty</th>
            <th style="text-align: right;">Unit Price</th>
            <th style="text-align: right;">Total</th>
        </tr>
    </thead>
    <tbody>
        <template data-bind="{{model.lineItems}}"
                  data-cache-styles="true"
                  data-style-identifier="invoice-lines">
            <tr>
                <td style="padding: 5pt;">{{.description}}</td>
                <td style="text-align: right; padding: 5pt;">{{.quantity}}</td>
                <td style="text-align: right; padding: 5pt;">${{.unitPrice}}</td>
                <td style="text-align: right; padding: 5pt; font-weight: bold;">${{.total}}</td>
            </tr>
        </template>
    </tbody>
</table>

7. Paginated Large Dataset

Combine caching with pagination:

<h1>Records 1-100 of {{count(model.allRecords)}}</h1>
<template data-bind="{{model.allRecords}}"
          data-bind-start="0"
          data-bind-max="100"
          data-cache-styles="true"
          data-style-identifier="record-page-1">
    <div style="padding: 5pt; border-bottom: 1pt solid #ddd; font-size: 9pt;">
        <strong>{{.id}}</strong> | {{.name}} | {{.value}}
    </div>
</template>

8. Nested Templates with Selective Caching

Cache outer template only:

<!-- Cache outer template (many categories) -->
<template data-bind="{{model.categories}}"
          data-cache-styles="true"
          data-style-identifier="category-headers">
    <div style="margin-bottom: 20pt;">
        <h2 style="color: #336699; border-bottom: 2pt solid #336699;">
            {{.categoryName}}
        </h2>

        <!-- Don't cache inner template (few items per category) -->
        <template data-bind="{{.products}}"
                  data-cache-styles="false">
            <div style="padding: 8pt; margin-left: 15pt;">
                {{.name}} - ${{.price}}
            </div>
        </template>
    </div>
</template>

9. Employee Directory

Large employee list with caching:

<style>
    .employee-card {
        padding: 12pt;
        margin-bottom: 8pt;
        border: 1pt solid #ddd;
        background-color: #f9f9f9;
    }
    .employee-name {
        font-weight: bold;
        font-size: 11pt;
    }
    .employee-details {
        font-size: 9pt;
        color: #666;
        margin-top: 3pt;
    }
</style>

<template data-bind="{{model.employees}}"
          data-cache-styles="true"
          data-style-identifier="employee-directory">
    <div class="employee-card">
        <div class="employee-name">{{.firstName}} {{.lastName}}</div>
        <div class="employee-details">
            {{.department}} | {{.title}}<br/>
            Email: {{.email}} | Phone: {{.phone}}
        </div>
    </div>
</template>

10. Transaction Log

High-volume transaction listing:

<h1>Transaction Log ({{count(model.transactions)}} transactions)</h1>
<table style="width: 100%; font-size: 9pt;">
    <thead>
        <tr style="background-color: #336699; color: white;">
            <th style="padding: 5pt;">Date</th>
            <th style="padding: 5pt;">ID</th>
            <th style="padding: 5pt;">Type</th>
            <th style="padding: 5pt; text-align: right;">Amount</th>
        </tr>
    </thead>
    <tbody>
        <template data-bind="{{model.transactions}}"
                  data-cache-styles="true"
                  data-style-identifier="transaction-rows">
            <tr>
                <td style="padding: 3pt;">{{.date}}</td>
                <td style="padding: 3pt;">{{.transactionId}}</td>
                <td style="padding: 3pt;">{{.type}}</td>
                <td style="padding: 3pt; text-align: right;">${{.amount}}</td>
            </tr>
        </template>
    </tbody>
</table>

11. Event Schedule

Large event listing with time-based grouping:

<style>
    .event-item {
        padding: 10pt;
        margin-bottom: 8pt;
        border-left: 4pt solid #336699;
        background-color: #f5f5f5;
    }
    .event-time {
        font-weight: bold;
        color: #336699;
    }
</style>

<template data-bind="{{model.events}}"
          data-cache-styles="true"
          data-style-identifier="event-schedule">
    <div class="event-item">
        <div class="event-time">{{.time}}</div>
        <div>{{.title}}</div>
        <div style="font-size: 9pt; color: #666;">{{.location}}</div>
    </div>
</template>

12. Inventory Report with Alternating Rows

Use CSS pseudo-classes with caching:

<style>
    .inventory-row {
        padding: 8pt;
        border-bottom: 1pt solid #ddd;
    }
    .inventory-row:nth-child(even) {
        background-color: #f9f9f9;
    }
</style>

<table style="width: 100%;">
    <template data-bind="{{model.inventoryItems}}"
              data-cache-styles="true"
              data-style-identifier="inventory-report">
        <tr class="inventory-row">
            <td>{{.sku}}</td>
            <td>{{.productName}}</td>
            <td style="text-align: right;">{{.quantity}}</td>
            <td style="text-align: right;">${{.value}}</td>
        </tr>
    </template>
</table>

13. Multi-Page Report with Consistent Styling

Cache styles across multiple report pages:

<style>
    .report-section {
        padding: 15pt;
        margin-bottom: 10pt;
        border: 1pt solid #ccc;
    }
</style>

<!-- Page 1 -->
<div style="page-break-after: always;">
    <h1>Section A</h1>
    <template data-bind="{{model.sectionA}}"
              data-cache-styles="true"
              data-style-identifier="report-sections">
        <div class="report-section">
            <h3>{{.title}}</h3>
            <p>{{.content}}</p>
        </div>
    </template>
</div>

<!-- Page 2 -->
<div style="page-break-after: always;">
    <h1>Section B</h1>
    <template data-bind="{{model.sectionB}}"
              data-cache-styles="true"
              data-style-identifier="report-sections">
        <div class="report-section">
            <h3>{{.title}}</h3>
            <p>{{.content}}</p>
        </div>
    </template>
</div>

14. Customer Mailing Labels

High-volume label generation:

<style>
    .mailing-label {
        width: 180pt;
        height: 90pt;
        padding: 10pt;
        border: 1pt solid #000;
        margin-bottom: 5pt;
        display: inline-block;
    }
</style>

<template data-bind="{{model.customers}}"
          data-cache-styles="true"
          data-style-identifier="mailing-labels">
    <div class="mailing-label">
        <div style="font-weight: bold;">{{.name}}</div>
        <div>{{.address1}}</div>
        <div>{{.address2}}</div>
        <div>{{.city}}, {{.state}} {{.zip}}</div>
    </div>
</template>

15. Performance Comparison Report

Demonstrate caching benefits with metrics:

<!-- Without caching (baseline) -->
<div style="page-break-after: always;">
    <h1>Test 1: Without Style Caching</h1>
    <p>Generation started: {{model.startTime}}</p>
    <template data-bind="{{model.testData}}"
              data-cache-styles="false">
        <div style="padding: 5pt; border-bottom: 1pt solid #ddd;">
            {{.id}} - {{.value}}
        </div>
    </template>
    <p>Generation ended: {{model.endTime}}</p>
    <p>Items processed: {{count(model.testData)}}</p>
</div>

<!-- With caching (optimized) -->
<div>
    <h1>Test 2: With Style Caching</h1>
    <p>Generation started: {{model.startTime}}</p>
    <template data-bind="{{model.testData}}"
              data-cache-styles="true"
              data-style-identifier="performance-test">
        <div style="padding: 5pt; border-bottom: 1pt solid #ddd;">
            {{.id}} - {{.value}}
        </div>
    </template>
    <p>Generation ended: {{model.endTime}}</p>
    <p>Items processed: {{count(model.testData)}}</p>
</div>

16. Sales Report with Summary Cards

Cache consistent card layout:

<style>
    .sales-card {
        padding: 12pt;
        margin-bottom: 10pt;
        border: 2pt solid #336699;
        background-color: #f0f8ff;
    }
    .sales-amount {
        font-size: 16pt;
        font-weight: bold;
        color: #336699;
    }
</style>

<template data-bind="{{model.salesData}}"
          data-cache-styles="true"
          data-style-identifier="sales-cards">
    <div class="sales-card">
        <div style="font-weight: bold;">{{.region}}</div>
        <div class="sales-amount">${{.totalSales}}</div>
        <div style="font-size: 9pt; color: #666;">
            {{.transactionCount}} transactions
        </div>
    </div>
</template>

17. Log File Viewer

Thousands of log entries with caching:

<style>
    .log-entry {
        font-family: 'Courier New', monospace;
        font-size: 8pt;
        padding: 2pt 5pt;
        border-bottom: 1pt solid #eee;
    }
</style>

<h1>Application Log</h1>
<p>Total entries: {{count(model.logEntries)}}</p>
<template data-bind="{{model.logEntries}}"
          data-bind-max="1000"
          data-cache-styles="true"
          data-style-identifier="log-entries">
    <div class="log-entry">
        [{{.timestamp}}] {{.level}} - {{.message}}
    </div>
</template>

18. Product Comparison Grid

Large comparison table with caching:

<table style="width: 100%; border-collapse: collapse;">
    <thead>
        <tr style="background-color: #336699; color: white;">
            <th style="padding: 8pt;">Feature</th>
            <th style="padding: 8pt;">Value</th>
            <th style="padding: 8pt;">Comparison</th>
        </tr>
    </thead>
    <tbody>
        <template data-bind="{{model.features}}"
                  data-cache-styles="true"
                  data-style-identifier="feature-rows">
            <tr>
                <td style="padding: 6pt; font-weight: bold;">{{.featureName}}</td>
                <td style="padding: 6pt;">{{.value}}</td>
                <td style="padding: 6pt; text-align: center;">{{.rating}}</td>
            </tr>
        </template>
    </tbody>
</table>

19. Batch Processing Status Report

Monitor large batch operations:

<h1>Batch Processing Report</h1>
<p>Processed: {{model.processedCount}} of {{count(model.batchItems)}}</p>

<style>
    .batch-item {
        padding: 6pt;
        border-bottom: 1pt solid #ddd;
        font-size: 9pt;
    }
    .status-success { color: green; }
    .status-error { color: red; }
    .status-pending { color: orange; }
</style>

<template data-bind="{{model.batchItems}}"
          data-cache-styles="true"
          data-style-identifier="batch-items">
    <div class="batch-item">
        <strong>{{.itemId}}</strong> - {{.description}}
        <span class="status-{{.status}}"> [{{.status}}]</span>
    </div>
</template>

20. Complex Nested Structure with Selective Caching

Optimize only high-volume sections:

<style>
    .section-header {
        background-color: #336699;
        color: white;
        padding: 10pt;
        margin-bottom: 10pt;
    }
    .subsection-item {
        padding: 5pt;
        margin-left: 15pt;
        border-left: 3pt solid #ccc;
    }
</style>

<!-- Don't cache outer (few departments) -->
<template data-bind="{{model.departments}}"
          data-cache-styles="false">
    <div style="margin-bottom: 30pt;">
        <div class="section-header">
            {{.departmentName}}
        </div>

        <!-- Cache inner (many employees per department) -->
        <template data-bind="{{.employees}}"
                  data-cache-styles="true"
                  data-style-identifier="employee-items">
            <div class="subsection-item">
                {{.name}} - {{.position}}
            </div>
        </template>
    </div>
</template>