Module: Sourcerer::YamlFrontmatter

Defined in:
lib/sourcerer/yaml_frontmatter.rb

Overview

Single owner of YAML frontmatter parsing across Sourcerer.

Both AsciiDoc pages (the Jekyll convention of embedding ----fenced YAML at the top of a .adoc file) and Markdown pages use the same syntax. All Sourcerer code that needs to detect, extract, or remove a frontmatter block delegates here instead of duplicating logic or constants.

Constant Summary collapse

REGEXP =

Matches a leading ----fenced YAML block at the start of a file. Content between the fences must be non-empty (.?+, lazy). The closing fence must be followed by a newline.

/\A(---\s*\n.+?\n)(---\s*\n)/m

Class Method Summary collapse

Class Method Details

.extract(source_text) ⇒ Hash

Parse the YAML frontmatter from source_text and return it as a Hash.

Returns an empty Hash when no frontmatter is present or when the YAML is malformed.

Parameters:

  • source_text (String)

Returns:

  • (Hash) 


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# File 'lib/sourcerer/yaml_frontmatter.rb', line 27

def extract source_text
  match = source_text.match(REGEXP)
  return {} unless match

  frontmatter_payload = match[1].sub(/\A---\s*\n/, '')
  parsed = YAML.safe_load(frontmatter_payload, aliases: true)
  parsed.is_a?(Hash) ? parsed : {}
rescue Psych::SyntaxError
  {}
end

.strip(source_text) ⇒ String

Return source_text with the leading YAML frontmatter block removed.

Parameters:

  • source_text (String)

Returns:

  • (String) 


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# File 'lib/sourcerer/yaml_frontmatter.rb', line 42

def strip source_text
  source_text.sub(REGEXP, '')
end