Module: AuditionHarness

Defined in:
lib/audition/dynamic/harness.rb

Defined Under Namespace

Classes: CapClassVar, CapIvar

Constant Summary collapse

MAX_CONSTS = 
5000
CAP_CONST =

Fixtures for capability probes.

[1, 2]

Class Method Summary collapse

Class Method Details

.base_env ⇒ Object 



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# File 'lib/audition/dynamic/harness.rb', line 328

def base_env
  {
    "REQUEST_METHOD" => "GET",
    "PATH_INFO" => "/",
    "QUERY_STRING" => "",
    "SERVER_NAME" => "localhost",
    "SERVER_PORT" => "80",
    "SERVER_PROTOCOL" => "HTTP/1.1",
    "rack.url_scheme" => "http",
    "rack.input" => StringIO.new(+""),
    "rack.errors" => StringIO.new(+"")
  }
end

.capabilities ⇒ Object

-- capabilities ------------------------------------------------



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# File 'lib/audition/dynamic/harness.rb', line 380

def capabilities
  caps = {}
  capability_probes.each do |label, probe|
    probe.call
    caps[label] = {"ok" => true, "error" => nil}
  rescue Exception => e
    caps[label] = {"ok" => false,
                    "error" => unwrap(e).class.name}
  end
  {"capabilities" => caps}
end

.capability_probes ⇒ Object 



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# File 'lib/audition/dynamic/harness.rb', line 392

def capability_probes
  {
    "global variable read" =>
      -> { Ractor.new { $audition_cap }.value }, # audition:disable
    "global variable write" =>
      -> { Ractor.new { $audition_cap = 1 }.value }, # audition:disable
    "class variable access" =>
      -> { Ractor.new { CapClassVar.read }.value },
    "class ivar write" =>
      -> { Ractor.new { CapIvar.write }.value },
    "class ivar read (mutable value)" =>
      -> { Ractor.new { CapIvar.read_mutable }.value },
    "unshareable constant read" =>
      -> { Ractor.new { CAP_CONST }.value },
    "constant set (unshareable value)" =>
      -> { Ractor.new { Object.const_set(:AUDITION_X, +"s") }.value },
    "ENV read" =>
      -> { Ractor.new { ENV.fetch("HOME", "none") }.value },
    "ENV write" =>
      -> { Ractor.new { ENV["AUD_CAP"] = "1" }.value }, # audition:disable
    "require inside Ractor" =>
      -> { Ractor.new { require "date" }.value }, # audition:disable
    "ObjectSpace.each_object" =>
      -> { Ractor.new { ObjectSpace.each_object(Class).first }.value },
    "Signal.trap" =>
      -> { Ractor.new { Signal.trap("USR2") {} }.value }, # audition:disable
    "Thread.current storage" =>
      -> { Ractor.new { Thread.current[:x] = 1 }.value },
    "Timeout.timeout" =>
      lambda do
        require "timeout" # audition:disable runtime-require
        Ractor.new { Timeout.timeout(2) { :ok } }.value
      end,
    "proc copied into Ractor" =>
      lambda do
        pr = proc { 1 }
        Ractor.new(pr) { |_p| :ok }.value
      end,
    "outer local capture" =>
      lambda do
        z = [1]
        Ractor.new { z }.value # audition:disable ractor-isolation
      end
  }
end

.describe_error(error) ⇒ Object

Exception messages can carry arbitrary bytes (C extensions, binary filenames); unscrubbed they blow up JSON.generate inside the rescue and the harness dies without output.



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# File 'lib/audition/dynamic/harness.rb', line 69

def describe_error(error)
  root = unwrap(error)
  {"class" => scrub(root.class.name.to_s),
   "message" => scrub(root.message.to_s)[0, 500]}
end

.in_ractor(*args, &block) ⇒ Object 



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# File 'lib/audition/dynamic/harness.rb', line 89

def in_ractor(*args, &block)
  ractor = Ractor.new(*args, &block)
  {"ok" => true, "value" => jsonable(ractor.value)}
rescue Exception => e
  {"ok" => false, "error" => describe_error(e)}
end

.inspect_module(full, mod, origin, class_state, class_vars) ⇒ Object 



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# File 'lib/audition/dynamic/harness.rb', line 225

def inspect_module(full, mod, origin, class_state, class_vars)
  ivars = mod.instance_variables
  if ivars.any?
    shareability = ivars.map do |ivar|
      value = mod.instance_variable_get(ivar)
      [ivar.to_s, safe_shareable?(value)]
    end
    class_state << origin.merge(
      "const" => full,
      "ivars" => shareability.map(&:first),
      "unshareable" => shareability.reject(&:last).map(&:first)
    )
  end
  cvars = mod.class_variables(false)
  if cvars.any?
    class_vars << origin.merge(
      "const" => full, "cvars" => cvars.map(&:to_s)
    )
  end
  0
rescue Exception
  1
end

.jsonable(value) ⇒ Object 



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# File 'lib/audition/dynamic/harness.rb', line 96

def jsonable(value)
  case value
  when Numeric, String, Symbol, true, false, nil then value
  else value.inspect[0, 200]
  end
end

.library(payload) ⇒ Object

-- libraries ---------------------------------------------------



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# File 'lib/audition/dynamic/harness.rb', line 123

def library(payload)
  Array(payload["load_paths"]).each do |lp|
    $LOAD_PATH.unshift(lp) # audition:disable global-variables
  end
  before = Object.constants
  feature = payload.fetch("feature")
  begin
    require feature # audition:disable runtime-require
  rescue LoadError
    # Dashed gem names conventionally ship slashed entry files
    # (rspec-mocks provides rspec/mocks).
    slashed = feature.tr("-", "/")
    raise if slashed == feature

    require slashed # audition:disable runtime-require
  end
  scan(Object.constants - before, root: payload["root"])
end

.main(mode, payload, out:) ⇒ Object 



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# File 'lib/audition/dynamic/harness.rb', line 44

def main(mode, payload, out:)
  result =
    case mode
    when "script_main" then script_main(payload.fetch("path"))
    when "script_ractor" then script_ractor(payload.fetch("path"))
    when "require" then library(payload)
    when "rack" then rack(payload)
    when "rails" then rails(payload)
    when "capabilities" then capabilities
    else {"error" => {"class" => "ArgumentError",
                      "message" => "unknown mode #{mode}"}}
    end
  out.puts(JSON.generate(result))
rescue Exception => e
  begin
    out.puts(JSON.generate("error" => describe_error(e)))
  rescue Exception
    out.puts('{"error":{"class":"HarnessFailure",' \
             '"message":"unreportable error"}}')
  end
end

.origin_for(owner, name, root) ⇒ Object

Where was this constant defined, and does that location belong to the audited target (as opposed to a dependency it loaded)? Unknown locations (C extensions, core) count as own so nothing gets silently downgraded.



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# File 'lib/audition/dynamic/harness.rb', line 213

def origin_for(owner, name, root)
  path, line = begin
    owner.const_source_location(name)
  rescue Exception
    nil
  end
  # The separator matters: /x/app must not claim /x/app-helpers.
  own = root.nil? || path.nil? || path == root ||
    path.start_with?(root + File::SEPARATOR)
  {"path" => path, "line" => line, "own" => own}
end

.rack(payload) ⇒ Object

App objects built in config.ru are almost never shareable (the file is instance_eval'd inside Rack::Builder, so every lambda's self is the Builder). Ractor web servers therefore boot the app once per Ractor; the probe mirrors that model: parse config.ru and serve one request entirely inside a Ractor.



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# File 'lib/audition/dynamic/harness.rb', line 262

def rack(payload)
  config_ru = payload.fetch("config_ru")
  begin
    require "rack" # audition:disable runtime-require
  rescue LoadError
    return {"rack_available" => false}
  end

  out = {"rack_available" => true}
  begin
    app = Rack::Builder.parse_file(config_ru)
    app = app.first if app.is_a?(Array)
    out["app_class"] = app.class.name
    out["shareable"] = Ractor.shareable?(app)
  rescue Exception => e
    out["main_boot_error"] = describe_error(e)
  end

  out["ractor_boot_call"] = rack_in_ractor(config_ru)
  if out["ractor_boot_call"]["ok"]
    out["concurrency"] = rack_concurrent(
      config_ru,
      payload.fetch("ractors", 4),
      payload.fetch("requests", 25)
    )
  end
  out
end

.rack_concurrent(config_ru, workers, requests) ⇒ Object

Real failures (races on shared state, require-proxy serialization) only show up under load: boot the app in N Ractors and serve M requests from each.



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# File 'lib/audition/dynamic/harness.rb', line 294

def rack_concurrent(config_ru, workers, requests)
  ractors = workers.times.map do
    Ractor.new(config_ru, requests) do |path, n|
      require "rack" # audition:disable runtime-require
      require "stringio" # audition:disable runtime-require
      builder = Rack::Builder.new
      builder.instance_eval(File.read(path), path, 1)
      app = builder.to_app
      statuses = Hash.new(0)
      n.times do
        statuses[app.call(AuditionHarness.base_env).first] += 1
      end
      statuses
    end
  end
  results = ractors.map do |ractor|
    {"ok" => true, "statuses" => ractor.value}
  rescue Exception => e
    {"ok" => false, "error" => describe_error(e)}
  end

  merged = Hash.new(0)
  results.each do |result|
    next unless result["ok"]

    result["statuses"].each { |code, n| merged[code.to_s] += n }
  end
  {"workers" => workers,
   "requests_per_worker" => requests,
   "failures" => results.count { |r| !r["ok"] },
   "first_error" => results.find { |r| !r["ok"] }&.dig("error"),
   "statuses" => merged}
end

.rack_in_ractor(config_ru) ⇒ Object

Rack::Builder.parse_file cannot run inside a Ractor at all on rack 3.2 (Rack::BUILDER_TOPLEVEL_BINDING holds an unshareable Binding), so the per-Ractor boot rebuilds the app by instance_eval'ing config.ru into a fresh Builder; same DSL, no poisoned constant.



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# File 'lib/audition/dynamic/harness.rb', line 347

def rack_in_ractor(config_ru)
  in_ractor(config_ru) do |path|
    require "rack" # audition:disable runtime-require
    require "stringio" # audition:disable runtime-require
    builder = Rack::Builder.new
    builder.instance_eval(File.read(path), path, 1)
    app = builder.to_app
    app.call(AuditionHarness.base_env).first
  end
end

.rails(payload) ⇒ Object

-- rails -------------------------------------------------------



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# File 'lib/audition/dynamic/harness.rb', line 360

def rails(payload)
  environment = payload.fetch("environment")
  before = Object.constants
  started = Time.now
  require environment # audition:disable runtime-require
  begin
    Rails.application.eager_load!
  rescue Exception
    nil
  end
  boot = {"ok" => true,
          "seconds" => (Time.now - started).round(1)}
  scan(Object.constants - before, root: payload["root"])
    .merge("boot" => boot)
rescue Exception => e
  {"boot" => {"ok" => false, "error" => describe_error(e)}}
end

.safe_shareable?(value) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/audition/dynamic/harness.rb', line 249

def safe_shareable?(value)
  Ractor.shareable?(value)
rescue Exception
  false
end

.scan(root_names, root: nil) ⇒ Object

Breadth-first walk of every constant the require introduced: plain values get a Ractor.shareable? verdict; classes and modules are inspected for class-level ivars and class variables, then descended into. const_get can raise (autoload failures) and anything can lie; every step is rescued and counted.



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# File 'lib/audition/dynamic/harness.rb', line 147

def scan(root_names, root: nil)
  # Loaded features are realpathed by require; the target root
  # must be too, or symlinked paths (macOS /var vs /private/var)
  # break the own-vs-dependency comparison.
  if root
    root = begin
      File.realpath(root)
    rescue
      root
    end
  end
  unshareable = []
  class_state = []
  class_vars = []
  errors = 0
  seen = {}
  queue = root_names.map { |name| [Object, name.to_s] }
  visited = 0

  until queue.empty?
    owner, name = queue.shift
    visited += 1
    break if visited > MAX_CONSTS

    begin
      value = owner.const_get(name, false)
    rescue Exception
      errors += 1
      next
    end
    full = owner.equal?(Object) ? name : "#{owner}::#{name}"
    origin = origin_for(owner, name, root)

    if value.is_a?(Module)
      next if seen[value.object_id]

      seen[value.object_id] = true
      errors += inspect_module(full, value, origin,
        class_state, class_vars)
      value.constants(false).each do |child|
        queue << [value, child.to_s]
      end
    else
      begin
        unless Ractor.shareable?(value)
          unshareable << origin.merge(
            "const" => full, "class" => value.class.name
          )
        end
      rescue Exception
        errors += 1
      end
    end
  end

  {"unshareable_constants" => unshareable,
   "class_state" => class_state,
   "class_variables" => class_vars,
   "scanned" => visited,
   "errors" => errors}
end

.script_main(path) ⇒ Object

-- scripts -----------------------------------------------------



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# File 'lib/audition/dynamic/harness.rb', line 105

def script_main(path)
  load path # audition:disable runtime-require
  {"ok" => true}
rescue Exception => e
  {"ok" => false, "error" => describe_error(e)}
end

.script_ractor(path) ⇒ Object

load is not proxied to the main Ractor (unlike require on Ruby 4.0), so the script body truly executes inside the Ractor.



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# File 'lib/audition/dynamic/harness.rb', line 114

def script_ractor(path)
  in_ractor(path) do |p|
    load p # audition:disable runtime-require
    :ok
  end
end

.scrub(text) ⇒ Object 



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# File 'lib/audition/dynamic/harness.rb', line 75

def scrub(text)
  text.dup.force_encoding(Encoding::UTF_8).scrub
rescue Exception
  "(unprintable)"
end

.unwrap(error) ⇒ Object 



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# File 'lib/audition/dynamic/harness.rb', line 81

def unwrap(error)
  if error.is_a?(Ractor::RemoteError) && error.cause
    error.cause
  else
    error
  end
end