Module: OpenTrace::SourceContext

Defined in:
lib/opentrace/source_context.rb

Constant Summary collapse

CONTEXT_LINES =

lines before and after the error line

3
MAX_CACHE_SIZE = 
50
MAX_FILE_SIZE =

100KB — skip generated/minified files

100_000

Class Method Summary collapse

Class Method Details

.clear_cache! ⇒ Object 



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# File 'lib/opentrace/source_context.rb', line 93

def clear_cache!
  @mutex.synchronize { @cache.clear }
end

.extract(backtrace_line) ⇒ Object

Extract source code context around a backtrace line. Returns nil if the file can’t be read.



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# File 'lib/opentrace/source_context.rb', line 16

def extract(backtrace_line)
  match = backtrace_line&.match(/\A(.+):(\d+)/)
  return nil unless match

  file = match[1]
  line_no = match[2].to_i
  return nil if line_no <= 0

  full_path = resolve_path(file)
  return nil unless full_path && File.exist?(full_path)
  return nil unless safe_path?(full_path)

  lines = read_file_lines(full_path)
  return nil unless lines

  start_line = [line_no - CONTEXT_LINES, 1].max
  end_line = [line_no + CONTEXT_LINES, lines.size].min

  context = {}
  (start_line..end_line).each do |n|
    context[n] = lines[n - 1]&.rstrip&.slice(0, 200)
  end

  {
    file: file,
    line: line_no,
    context: context
  }
rescue StandardError
  nil
end

.read_file_lines(path) ⇒ Object 



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# File 'lib/opentrace/source_context.rb', line 77

def read_file_lines(path)
  @mutex.synchronize do
    return @cache[path] if @cache.key?(path)

    if @cache.size >= MAX_CACHE_SIZE
      @cache.delete(@cache.keys.first)
    end

    lines = File.readlines(path)
    @cache[path] = lines
    lines
  end
rescue StandardError
  nil
end

.resolve_path(file) ⇒ Object 



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# File 'lib/opentrace/source_context.rb', line 48

def resolve_path(file)
  if file.start_with?("/")
    file
  elsif defined?(::Rails) && ::Rails.respond_to?(:root) && ::Rails.root
    File.join(::Rails.root.to_s, file)
  else
    File.expand_path(file)
  end
rescue StandardError
  nil
end

.safe_path?(path) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/opentrace/source_context.rb', line 60

def safe_path?(path)
  return false unless path.include?("/app/") || path.include?("/lib/") || path.include?("/config/")

  # Resolve symlinks and '..' to prevent path traversal
  real = File.realpath(path)

  # Verify the resolved path is under the application root
  if defined?(::Rails) && ::Rails.respond_to?(:root) && ::Rails.root
    root = ::Rails.root.to_s
    return false unless real.start_with?("#{root}/")
  end

  File.size(real) <= MAX_FILE_SIZE
rescue StandardError
  false
end