Class: MockServer::BinaryLauncher

Inherits:
Object
  • Object
show all
Defined in:
lib/mockserver/binary_launcher.rb

Overview

On-demand binary launcher for MockServer.

Downloads the self-contained, JVM-less MockServer bundle (a jlink runtime + the server + a mockserver launcher) for the current platform from the GitHub Release, verifies its SHA-256, caches it per-user, and launches it. No Java installation and no Docker required.

This mirrors the reference implementation at mockserver-node/downloadBinary.js.

Environment overrides:

MOCKSERVER_BINARY_BASE_URL       mirror host for the release assets
MOCKSERVER_BINARY_CACHE          cache directory (default: per-OS user cache)
MOCKSERVER_SKIP_BINARY_DOWNLOAD  fail instead of downloading (air-gapped CI with pre-seeded cache)
HTTP_PROXY / HTTPS_PROXY         honoured by Net::HTTP via +ENV['http_proxy']+ (Ruby convention)
SSL_CERT_FILE / SSL_CERT_DIR     honoured by OpenSSL for corporate TLS proxies

Examples:

Start a server on port 1080

handle = MockServer::BinaryLauncher.start(port: 1080)
# ... use MockServer ...
handle.stop

Just ensure the binary is present

path = MockServer::BinaryLauncher.ensure_launcher

Defined Under Namespace

Classes: ServerHandle

Constant Summary collapse

REPO = 
'mock-server/mockserver-monorepo'
SNAPSHOT_CDN =

CDN base URL used for SNAPSHOT version downloads.

'https://downloads.mock-server.com'
MAX_PREVIOUS_VERSIONS_TO_KEEP =

Maximum number of previous version directories to keep (in addition to the current).

1
VERSION_PATTERN =

Strict pattern for version strings — blocks path separators and ‘..’.

/\A[0-9]+\.[0-9]+\.[0-9]+([-.][0-9A-Za-z.]+)?\z/

Class Method Summary collapse

Class Method Details

.asset_url(version, file) ⇒ String

Return the download URL for a release asset.

Uses MOCKSERVER_BINARY_BASE_URL if set; otherwise defaults to GitHub Releases for release versions and the downloads.mock-server.com CDN for SNAPSHOT versions.

Parameters:

  • version (String)
  • file (String)

Returns:

  • (String) 


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# File 'lib/mockserver/binary_launcher.rb', line 105

def asset_url(version, file)
  base = ENV['MOCKSERVER_BINARY_BASE_URL'] ||
         if snapshot?(version)
           "#{SNAPSHOT_CDN}/mockserver-#{version}"
         else
           "https://github.com/#{REPO}/releases/download/mockserver-#{version}"
         end
  # Strip trailing slashes with a single linear scan rather than a regex,
  # so there is no ReDoS surface at all (CWE-1333) on the operator-supplied
  # MOCKSERVER_BINARY_BASE_URL. Interior slashes are preserved; only the
  # trailing run is removed.
  last = base.length
  last -= 1 while last.positive? && base[last - 1] == '/'
  "#{base[0, last]}/#{file}"
end

.bundle_base_name(version) ⇒ Hash

Return the bundle base name and extension for a given version.

Parameters:

  • version (String)

Returns:

  • (Hash) —

    with keys :name and :ext



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# File 'lib/mockserver/binary_launcher.rb', line 72

def bundle_base_name(version)
  platform = resolve_platform
  {
    name: "mockserver-#{version}-#{platform[:os_name]}-#{platform[:arch]}",
    ext: platform[:ext]
  }
end

.cache_dir ⇒ String

Return the per-user cache directory for MockServer binaries.

Returns:

  • (String) 


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# File 'lib/mockserver/binary_launcher.rb', line 83

def cache_dir
  if ENV['MOCKSERVER_BINARY_CACHE'] && !ENV['MOCKSERVER_BINARY_CACHE'].empty?
    return ENV['MOCKSERVER_BINARY_CACHE']
  end

  base = if windows?
           ENV['LOCALAPPDATA'] || File.join(Dir.home, 'AppData', 'Local')
         else
           ENV['XDG_CACHE_HOME'] || File.join(Dir.home, '.cache')
         end
  File.join(base, 'mockserver', 'binaries')
end

.ensure_launcher(version: nil, log: nil) ⇒ String

Ensure the platform bundle is present and return the launcher path, downloading + verifying + extracting + caching on first use.

Parameters:

  • version (String) (defaults to: nil) —

    the MockServer version (defaults to MockServer::VERSION)

  • log (Logger, nil) (defaults to: nil) —

    optional logger

Returns:

  • (String) —

    absolute path to the launcher executable

Raises:

  • (Error) —

    on download/verification failure



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# File 'lib/mockserver/binary_launcher.rb', line 138

def ensure_launcher(version: nil, log: nil)
  version ||= MockServer::VERSION
  log ||= Logger.new($stderr, level: Logger::WARN)

  validate_version!(version)

  meta = bundle_base_name(version)
  base = cache_dir
  dir = File.join(base, version)
  launcher = launcher_path(dir, meta[:name])

  # H1: Assert version dir stays within cache base (path traversal guard)
  assert_within_base!(dir, base)

  # Check cache
  if File.exist?(launcher) && File.size(launcher) > 0
    log.info("Using cached binary: #{launcher}")
    # Contract section 7: prune only after a successful install, not on cache hit
    return launcher
  end

  # Skip-download check
  if ENV['MOCKSERVER_SKIP_BINARY_DOWNLOAD'] && !ENV['MOCKSERVER_SKIP_BINARY_DOWNLOAD'].empty?
    raise Error, "MOCKSERVER_SKIP_BINARY_DOWNLOAD is set but no cached binary at #{launcher}"
  end

  FileUtils.mkdir_p(dir)
  archive_file = "#{meta[:name]}.#{meta[:ext]}"
  archive = File.join(dir, archive_file)
  partial = "#{archive}.part"
  sha_file = "#{archive}.sha256"

  begin
    # Download to a temp file
    url = asset_url(version, archive_file)
    log.info("Downloading #{url}")
    download_file(url, partial)

    # Verify SHA-256 (fail-closed — always required, no bypass)
    sha_url = asset_url(version, "#{archive_file}.sha256")
    download_file(sha_url, sha_file)
    raw = File.read(sha_file, encoding: 'utf-8').strip
    expected = raw.split(/\s+/).first
    if expected.nil? || expected.empty?
      raise Error, "checksum file for #{meta[:name]} is empty or unparseable"
    end

    actual = Digest::SHA256.file(partial).hexdigest
    if expected != actual
      raise Error,
            "checksum mismatch for #{meta[:name]}: expected #{expected}, got #{actual}"
    end
    log.info('Checksum verified')

    File.rename(partial, archive)
  rescue StandardError
    # H3: Best-effort cleanup of BOTH .part and .sha256 temp files on failure
    File.delete(partial) if File.exist?(partial)
    File.delete(sha_file) if File.exist?(sha_file)
    raise
  end

  # Extract the archive into the version directory.
  log.info("Extracting #{archive}")
  extract_archive(archive, dir, meta[:ext])

  # H3: Post-extract path traversal guard — enumerate every extracted entry
  # and verify it resolves within the version directory. If any entry escaped
  # (via ../ or absolute paths in the archive), abort with a clear error.
  verify_extracted_paths!(dir)

  unless File.exist?(launcher) && File.size(launcher) > 0
    raise Error, "launcher missing or empty after extract: #{launcher}"
  end

  File.chmod(0o755, launcher) unless windows?

  # Contract section 7: prune after successful install
  prune_old_versions(version, log: log)

  launcher
end

.launcher_path(dir, bundle_name) ⇒ String

Return the expected launcher path inside a versioned cache directory.

Parameters:

  • dir (String) —

    the version directory

  • bundle_name (String) —

    the bundle base name

Returns:

  • (String) 


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# File 'lib/mockserver/binary_launcher.rb', line 126

def launcher_path(dir, bundle_name)
  exe = windows? ? 'mockserver.bat' : 'mockserver'
  File.join(dir, bundle_name, 'bin', exe)
end

.prune_old_versions(current_version, log: nil) ⇒ void

This method returns an undefined value.

Remove old version directories from the cache, keeping the current version and at most MAX_PREVIOUS_VERSIONS_TO_KEEP previous versions.

Uses semver-aware numeric segment comparison (H7) rather than lexicographic or mtime-based ordering.

Parameters:

  • current_version (String)
  • log (Logger, nil) (defaults to: nil) 


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# File 'lib/mockserver/binary_launcher.rb', line 253

def prune_old_versions(current_version, log: nil)
  log ||= Logger.new($stderr, level: Logger::WARN)
  base = cache_dir

  return unless File.directory?(base)

  entries = Dir.entries(base).select do |entry|
    next false if entry == '.' || entry == '..'

    full = File.join(base, entry)
    # Only consider directories (version directories) — never files
    File.directory?(full)
  rescue Errno::ENOENT
    # Directory vanished between Dir.entries and File.directory? — skip
    false
  end

  # Separate current from old
  old_entries = entries.reject { |e| e == current_version }

  # H7: Sort old entries by semver-aware numeric comparison (highest first = kept)
  old_sorted = old_entries.sort { |a, b| compare_versions(b, a) }

  # Keep at most MAX_PREVIOUS_VERSIONS_TO_KEEP
  to_remove = old_sorted.drop(MAX_PREVIOUS_VERSIONS_TO_KEEP)
  to_remove.each do |name|
    full = File.join(base, name)
    begin
      # Safety: never delete outside the cache dir
      real_base = File.realpath(base)
      real_full = File.realpath(full)
      unless real_full.start_with?(real_base + File::SEPARATOR) || real_full == real_base
        log.warn("Skipping suspicious path during prune: #{full}")
        next
      end

      log.info("Pruning old version cache: #{name}")
      FileUtils.rm_rf(full)
    rescue Errno::ENOENT, Errno::EACCES => e
      # COR-06: directory vanished concurrently or permission denied — skip gracefully
      log.warn("Skipping during prune (#{e.class}): #{full}")
      next
    end
  end

  # Clean up leftover .part and .sha256 temp files at ALL levels (not just base)
  Dir.glob(File.join(base, '**', '*.part')).each do |part_file|
    log.info("Removing leftover temp file: #{part_file}")
    File.delete(part_file)
  rescue StandardError => e
    log.warn("Failed to remove temp file #{part_file}: #{e.message}")
  end

  Dir.glob(File.join(base, '**', '*.sha256')).each do |sha_file|
    # Only remove orphaned .sha256 files (where the corresponding archive is absent)
    archive_path = sha_file.sub(/\.sha256\z/, '')
    next if File.exist?(archive_path)

    log.info("Removing orphaned checksum file: #{sha_file}")
    File.delete(sha_file)
  rescue StandardError => e
    log.warn("Failed to remove checksum file #{sha_file}: #{e.message}")
  end
end

.resolve_platform ⇒ Hash

Resolve the current platform to the bundle naming tokens.

Returns:

  • (Hash) —

    with keys :os_name, :arch, :ext

Raises:

  • (Error) —

    on unsupported platform or architecture



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# File 'lib/mockserver/binary_launcher.rb', line 51

def resolve_platform
  os_name, ext = case RbConfig::CONFIG['host_os']
                 when /linux/i    then ['linux', 'tar.gz']
                 when /darwin/i   then ['darwin', 'tar.gz']
                 when /mswin|mingw|cygwin/i then ['windows', 'zip']
                 else raise Error, "unsupported platform: #{RbConfig::CONFIG['host_os']}"
                 end

  arch = case RbConfig::CONFIG['host_cpu']
         when /x86_64|x64|amd64/i then 'x86_64'
         when /aarch64|arm64/i     then 'aarch64'
         else raise Error, "unsupported architecture: #{RbConfig::CONFIG['host_cpu']}"
         end

  { os_name: os_name, arch: arch, ext: ext }
end

.start(port:, version: nil, extra_args: [], log: nil) ⇒ ServerHandle

Start a MockServer instance on the given port.

Parameters:

  • port (Integer) —

    the server port

  • version (String, nil) (defaults to: nil) —

    the MockServer version

  • extra_args (Array<String>) (defaults to: []) —

    additional CLI arguments

  • log (Logger, nil) (defaults to: nil) —

    optional logger

Returns:



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# File 'lib/mockserver/binary_launcher.rb', line 228

def start(port:, version: nil, extra_args: [], log: nil)
  launcher = ensure_launcher(version: version, log: log)
  args = ['-serverPort', port.to_s] + extra_args

  # H4: On Windows, .bat files must be invoked via cmd.exe /c.
  # H5: Drain stdout/stderr via :out/:err redirection to avoid pipe-buffer deadlock.
  pid = if windows?
          Process.spawn('cmd.exe', '/c', launcher, *args,
                        out: File::NULL, err: File::NULL)
        else
          Process.spawn(launcher, *args,
                        out: File::NULL, err: File::NULL)
        end
  ServerHandle.new(pid: pid, port: port, launcher: launcher)
end