Module: LaunchDarklyObservability::SourceContext

Defined in:
lib/launchdarkly_observability/source_context.rb

Constant Summary collapse

CONTEXT_LINES = 
4
MAX_FRAMES = 
20
MAX_LINE_LENGTH = 
1000
BACKTRACE_LINE_PATTERN = 
/^(.+):(\d+)(?::in [`'](.+?)')?$/

Class Method Summary collapse

Class Method Details

.build_structured_stacktrace(exception) ⇒ Object 



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

def build_structured_stacktrace(exception)
  return nil unless exception

  backtrace = exception.backtrace
  return nil unless backtrace&.any?

  error_message = begin
    exception.full_message(highlight: false, order: :top).to_s.lines.first&.chomp
  rescue StandardError
    exception.message
  end
  frames = backtrace.first(MAX_FRAMES).filter_map do |backtrace_line|
    build_frame(backtrace_line, error_message)
  end

  frames.empty? ? nil : frames
rescue StandardError
  nil
end

.exception_attributes(exception) ⇒ Hash

Build a Hash of span attributes for an exception’s structured stacktrace. Returns an empty hash when no stacktrace can be built, so the result is safe to merge directly into an attributes hash.

Parameters:

  • exception (Exception)

Returns:

  • (Hash) 


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# File 'lib/launchdarkly_observability/source_context.rb', line 42

def exception_attributes(exception)
  stacktrace = build_structured_stacktrace(exception)
  return {} unless stacktrace

  { 'exception.structured_stacktrace' => stacktrace.to_json }
end

.read_source_context(file_name, line_number) ⇒ Object 



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# File 'lib/launchdarkly_observability/source_context.rb', line 49

def read_source_context(file_name, line_number)
  return nil unless file_name && line_number
  return nil unless File.exist?(file_name) && File.readable?(file_name)

  source_lines = cached_source_lines(file_name)
  return nil unless source_lines
  return nil if line_number <= 0 || line_number > source_lines.length

  target_index = line_number - 1
  before_start = [target_index - CONTEXT_LINES, 0].max
  before_lines = source_lines[before_start...target_index] || []
  after_end = [target_index + CONTEXT_LINES, source_lines.length - 1].min
  after_lines = source_lines[(target_index + 1)..after_end] || []

  {
    lineContent: source_lines[target_index],
    linesBefore: before_lines.empty? ? nil : before_lines.join("\n"),
    linesAfter: after_lines.empty? ? nil : after_lines.join("\n")
  }
rescue StandardError
  nil
end