s3 ファイル取得用クライアント

# coding: utf-8

require "aws-sdk"

S3_SAVE_DIR = "s3/"
ALL_FILE_DOWNLOAD = "全てのファイルを落とす"

s3 = AWS::S3.new(
  access_key_id: "YOUR AWS ACCESS KEY"
  secret_access_key: "YOUR AWS SECRET"
)

def show_item_with_pointer(iterator, console_print = true)
  rtn_hash = {}
  iterator.each_with_index do |value, idx|
    rtn_hash[idx.to_s] = value
    if console_print
      p "[" + (idx).to_s + "] " + value.inspect.to_s
    end
  end

  rtn_hash
end

def ls(tree)
  ls = []
  directories = tree.children.select(&:branch?).collect(&:prefix)
  files = tree.children.select(&:leaf?).collect(&:key)

  #all_select = files.length > 1 ?  [ALL_FILE_DOWNLOAD] : []
  all_select = [ALL_FILE_DOWNLOAD]
  ls = all_select.concat(directories.concat(files))
end

def get_or_into_directory_recursive(tree)
  file_and_directories = show_item_with_pointer(ls(tree))

  idx = gets_from_stdin("fileまたはdirectoryを数値で選択")

  file_or_directory = file_and_directories[idx]

  # select dir
  if file_or_directory.end_with?("/")
    tree = @bucket.as_tree({prefix: file_or_directory})
    objs = get_or_into_directory_recursive(tree)
  else
    objs = []
    # select all
    if file_or_directory == ALL_FILE_DOWNLOAD
      objs = get_objects(file_and_directories)
    # select file
    else
      objs << @bucket.objects[file_or_directory]
    end
  end

  return objs
end

# http://qiita.com/riocampos/items/cf71862bf975e13bdb4a
def progress_bar(i, max = 100)
  i = i.to_f
  max = max.to_f
  i = max if i > max
  percent = i / max * 100.0
  rest_size = 1 + 5 + 1 # space + progress_num + %
  bar_size = 79 - rest_size # (width - 1) - rest_size
  bar_str = '%-*s' % [bar_size, ('#' * (percent * bar_size / 100).to_i)]
  progress_num = '%3.1f' % percent
  print "\r#{bar_str} #{'%5s' % progress_num}%"
end


def get_objects(file_and_directories)
  objs = []
  file_and_directories.each do |idx, path|
    next if path == ALL_FILE_DOWNLOAD
    if path.end_with?("/")
      tree = @bucket.as_tree({prefix: path})
      recursive_file_and_directories = show_item_with_pointer(ls(tree), false)
      objs.concat(get_objects(recursive_file_and_directories))
    else
      objs << @bucket.objects[path]
    end
  end

  objs
end

def gets_from_stdin(message = nil)
  print message unless message.nil?
  str = STDIN.gets.chomp
end


def get_y_or_n_from_stdin(message)
  bol = ""
  while !%w(Y N).include?(bol.upcase)
    bol = gets_from_stdin("#{message}(y/n)")
  end
  bol.upcase == "Y"
end

all_buckets = show_item_with_pointer(s3.buckets)

idx = gets_from_stdin("bucketを数値で選択")

@bucket = all_buckets[idx]
tree = @bucket.as_tree

files = get_or_into_directory_recursive(tree)

s3_dir = File.expand_path(S3_SAVE_DIR)

# gz圧縮なら解凍するか問う
extract_bol = if files.any?{|file| file.key.include?("gz")}
                get_y_or_n_from_stdin("解凍を同時に行いますか？")
              else
                false
              end

# 正規表現抜き出しを行うか問う
regexp = nil
if get_y_or_n_from_stdin("正規表現によるファイル名絞り込みを行いますか？")
  regexp = Regexp.new(gets_from_stdin("正規表現を入力してください"))

  files = files.reject do |file|
    file_path = [s3_dir,file.key].join("/")
    File.basename(file_path).match(regexp).nil?
  end

end

# 保存処理
files.each.with_index(1) do |file, idx|
  file_path = [s3_dir,file.key].join("/")
  dir = File.dirname(file_path)
  FileUtils.mkdir_p(dir)

  File.open(file_path, 'wb') do |f|
    file.read do |chunk|
      f.write(chunk)
    end
  end

  if extract_bol
    `gunzip #{file_path}`
  end

  progress_bar((idx.to_f / files.length) * 100)
end