Search

NDG includes a built-in search system that indexes your documentation pages and their headings, enabling quick navigation through your content. Search is optional and can be configured to control indexing depth and behavior.

Configuration

Search behavior is configured through the [search] section in your ndg.toml file or via CLI flags.

[search]
enable = true
max_heading_level = 3

Or using CLI overrides:

ndg html --config search.enable=true --config search.max_heading_level=4

Options

Search Behavior

Hierarchical Results

Search results are displayed hierarchically with pages as parent items and matching headings as nested children beneath them:

Getting Started                    (page result)
  ↳ Installation Requirements      (H2 heading)
  ↳ Quick Start Guide              (H2 heading)

Configuration                      (page result)
  ↳ Basic Configuration            (H2 heading)
  ↳ Advanced Options               (H3 heading)

This structure helps you navigate directly to relevant sections within pages rather than just finding pages.

Scoring Algorithm

Search uses a two-pass scoring system:

1. Page scoring - Pages are scored based on title and content matches
2. Anchor scoring - Headings within high-scoring pages are scored based on heading text

Only headings from pages with sufficient relevance to the search query are shown, preventing irrelevant section matches from cluttering results.

Tokenization

Search queries and content are tokenized (split into words) for matching:

• Case-insensitive matching
• Partial word matches supported
• Special characters are normalized
• Stop words (common words like "the", "a") are preserved

Example:

Query: "config file" matches:

• "Configuration Files"
• "config.toml file format"
• "Loading configuration from files"

Performance Considerations

Index Size

Search index size increases with:

• Number of documentation pages
• Amount of text content per page
• max_heading_level setting (higher = more headings indexed)