Class: Mxrb::Scaffold::Transaction

Inherits:
Object
  • Object
show all
Defined in:
lib/mxrb/scaffold/transaction.rb

Overview

Applies a set of file creations and replacements with rollback on failure.

Defined Under Namespace

Classes: Change

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Transaction

Returns a new instance of Transaction.



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# File 'lib/mxrb/scaffold/transaction.rb', line 11

def initialize
  @changes = {}
  @created = []
  @updated = []
end

Instance Attribute Details

#created ⇒ Object (readonly)

Returns the value of attribute created.



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# File 'lib/mxrb/scaffold/transaction.rb', line 9

def created
  @created
end

#updated ⇒ Object (readonly)

Returns the value of attribute updated.



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# File 'lib/mxrb/scaffold/transaction.rb', line 9

def updated
  @updated
end

Instance Method Details

#commit ⇒ Object 



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# File 'lib/mxrb/scaffold/transaction.rb', line 41

def commit
  applied = []
  @changes.each_value do |change|
    apply(change)
    applied << change
  end
rescue StandardError
  applied.reverse_each { rollback(_1) }
  raise
ensure
  cleanup_staging
end

#content(path) ⇒ Object 



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# File 'lib/mxrb/scaffold/transaction.rb', line 17

def content(path)
  return @changes.fetch(path).content if @changes.key?(path)
  return File.binread(path) if File.file?(path)

  nil
end

#create(path, content) ⇒ Object 



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# File 'lib/mxrb/scaffold/transaction.rb', line 24

def create(path, content)
  abort "#{path}: file already exists" if File.exist?(path) || @changes.key?(path)

  @created << path
  @changes[path] = Change.new(path, content, nil, 0o644)
end

#write(path, new_content) ⇒ Object 



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# File 'lib/mxrb/scaffold/transaction.rb', line 31

def write(path, new_content)
  original = content(path)
  return create(path, new_content) unless original
  return if original == new_content

  @updated << path unless @updated.include?(path)
  mode = File.stat(path).mode
  @changes[path] = Change.new(path, new_content, File.binread(path), mode)
end