Class: Rwm::TaskCache

Inherits:
Object
  • Object
show all
Defined in:
lib/rwm/task_cache.rb

Instance Method Summary collapse

Constructor Details

#initialize(workspace, graph) ⇒ TaskCache

Returns a new instance of TaskCache.



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# File 'lib/rwm/task_cache.rb', line 10

def initialize(workspace, graph)
  @workspace = workspace
  @graph = graph
  @cache_dir = File.join(workspace.root, ".rwm", "cache")
  @content_hashes = {}
  @cache_declarations = {}
end

Instance Method Details

#cache_declarations(package) ⇒ Object

Discover cacheable task declarations by running ‘bundle exec rake rwm:cache_config`



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# File 'lib/rwm/task_cache.rb', line 78

def cache_declarations(package)
  return @cache_declarations[package.name] if @cache_declarations.key?(package.name)

  output = `cd #{Shellwords.escape(package.path)} && bundle exec rake rwm:cache_config 2>/dev/null`
  @cache_declarations[package.name] = if $?.success? && !output.strip.empty?
                                         JSON.parse(output.strip)
                                       else
                                         {}
                                       end
rescue JSON::ParserError
  @cache_declarations[package.name] = {}
end

#cacheable?(package, task) ⇒ Boolean

Returns true if the task is declared cacheable in the package’s Rakefile

Returns:

  • (Boolean) 


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# File 'lib/rwm/task_cache.rb', line 19

def cacheable?(package, task)
  declarations = cache_declarations(package)
  declarations.key?(task)
end

#cached?(package, task) ⇒ Boolean

Returns true if the (package, task) pair is cached and inputs haven’t changed. Also verifies declared outputs exist (if any).

Returns:

  • (Boolean) 


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# File 'lib/rwm/task_cache.rb', line 26

def cached?(package, task)
  stored = read_stored_hash(package, task)
  return false unless stored
  return false unless stored == content_hash(package)

  # If outputs are declared, they must exist
  decl = cache_declarations(package)[task]
  if decl && decl["output"]
    return false unless outputs_exist?(package, decl["output"])
  end

  true
end

#content_hash(package) ⇒ Object

Compute a content hash for a package: SHA256 of all source files + dependency hashes



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# File 'lib/rwm/task_cache.rb', line 54

def content_hash(package)
  return @content_hashes[package.name] if @content_hashes.key?(package.name)

  digest = Digest::SHA256.new

  # Hash all source files in the package (sorted for determinism)
  source_files(package).each do |file|
    rel_path = file.delete_prefix("#{package.path}/")
    digest.update(rel_path)
    digest.update(File.read(file))
  end

  # Include dependency content hashes (transitive invalidation)
  @graph.dependencies(package.name).sort.each do |dep_name|
    dep_pkg = @workspace.find_package(dep_name)
    digest.update(content_hash(dep_pkg))
  rescue PackageNotFoundError
    next
  end

  @content_hashes[package.name] = digest.hexdigest
end

#outputs_exist?(package, output_pattern) ⇒ Boolean

Check if declared output files/globs exist in the package directory

Returns:

  • (Boolean) 


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# File 'lib/rwm/task_cache.rb', line 48

def outputs_exist?(package, output_pattern)
  matches = Dir.glob(File.join(package.path, output_pattern))
  !matches.empty?
end

#store(package, task) ⇒ Object

Store the current content hash after a successful task run



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# File 'lib/rwm/task_cache.rb', line 41

def store(package, task)
  FileUtils.mkdir_p(@cache_dir)
  path = cache_file(package, task)
  File.write(path, content_hash(package))
end