middleman/middleman-core/lib/middleman-core/util/data.rb

154 lines
3.9 KiB
Ruby

# Core Pathname library used for traversal
require 'pathname'
# DbC
require 'middleman-core/contracts'
# Shared util methods
require 'middleman-core/util'
# Parsing YAML data
require 'yaml'
# Parsing JSON data
require 'json'
module Middleman
module Util
module Data
include Contracts
module_function
YAML_ERRORS = [StandardError]
# https://github.com/tenderlove/psych/issues/23
if defined?(Psych) && defined?(Psych::SyntaxError)
YAML_ERRORS << Psych::SyntaxError
end
# Get the frontmatter and plain content from a file
# @param [String] path
# @return [Array<Hash, String>]
Contract Pathname, Maybe[Symbol] => [Hash, Maybe[String]]
def parse(full_path, known_type=nil)
data = {}
return [data, nil] if ::Middleman::Util.binary?(full_path)
# Avoid weird race condition when a file is renamed.
content = begin
File.read(full_path)
rescue ::EOFError
rescue ::IOError
rescue ::Errno::ENOENT
''
end
begin
if content =~ /\A.*coding:/
lines = content.split(/\n/)
lines.shift
content = lines.join("\n")
end
if known_type
if known_type == :yaml
result = parse_yaml(content, full_path, true)
elsif known_type == :json
result = parse_json(content, full_path)
end
else
result = parse_yaml(content, full_path, false)
end
return result if result
rescue
# Probably a binary file, move on
end
[data, content]
end
# Parse YAML frontmatter out of a string
# @param [String] content
# @return [Array<Hash, String>]
Contract String, Pathname, Bool => Maybe[[Hash, String]]
def parse_yaml(content, full_path, require_yaml=false)
total_delims = content.scan(/^(?:---|\.\.\.)\s*(?:\n|$)/).length
has_first_line_delim = !content.match(/\A(---\s*(?:\n|$))/).nil?
# has_closing_delim = (total_delims > 1 && has_first_line_delim) || (!has_first_line_delim && total_delims == 1)
parts = content.split(/^(?:---|\.\.\.)\s*(?:\n|$)/)
parts.shift if parts[0].empty?
yaml_string = nil
additional_content = nil
if require_yaml
yaml_string = parts[0]
additional_content = parts[1]
else
if total_delims > 1
if has_first_line_delim
yaml_string = parts[0]
additional_content = parts[1]
else
additional_content = content
end
else
additional_content = parts[0]
end
end
return [{}, additional_content] if yaml_string.nil?
begin
data = map_value(::YAML.load(yaml_string) || {})
rescue *YAML_ERRORS => e
$stderr.puts "YAML Exception parsing #{full_path}: #{e.message}"
return nil
end
[data, additional_content]
rescue
[{}, additional_content]
end
# Parse JSON frontmatter out of a string
# @param [String] content
# @return [Array<Hash, String>]
Contract String, Pathname => Maybe[[Hash, String]]
def parse_json(content, full_path)
begin
data = map_value(::JSON.parse(content))
rescue => e
$stderr.puts "JSON Exception parsing #{full_path}: #{e.message}"
return nil
end
[data, nil]
rescue
[{}, nil]
end
def symbolize_recursive(hash)
{}.tap do |h|
hash.each { |key, value| h[key.to_sym] = map_value(value) }
end
end
def map_value(thing)
case thing
when Hash
symbolize_recursive(thing)
when Array
thing.map { |v| map_value(v) }
else
thing
end
end
end
end
end