formatting comments

n3

#!/usr/bin/env ruby

# Using AWS S3 to make sharing files with your friends as simple as can be...
# ... or something.
# 
# Only tested on OS X.
#
# usage: n3 [put|get|list|delete|open|help]

[
  "AWS_N3_BUCKET",
  "AWS_ACCESS_KEY_ID",
  "AWS_SECRET_ACCESS_KEY",
  "AWS_REGION"
].each do |expected_var|
  unless ENV[expected_var]
    puts "!!! WARNING !!!"
    puts "Missing enviroment variable #{expected_var}"
    puts "The following variables are expected to be set: #{expected_env_vars.join(", ")}"
    puts "Exiting."
    exit
  end
end

USAGE_TEXT = "usage: n3 [put|get|list|delete|open|help]"

if ARGV.size < 1
  puts USAGE_TEXT
else

  begin
    require "aws-sdk"
    require "ruby-progressbar"
  rescue LoadError
    puts "Missing gems. To install all the required gems try:"
    puts
    puts "  gem install aws-sdk ruby-progressbar"
    puts
    puts "Exiting."
    exit
  end

  BUCKET = ENV["AWS_N3_BUCKET"]

  $n3_aws_client = Aws::S3::Client.new
  $n3_aws_client.create_bucket(bucket: BUCKET)

  command, *arguments = ARGV
  case command
  when "get"
    if file = arguments.first
      new_file = Dir.pwd + "/" + file
      puts "Creating #{new_file}"
      $n3_aws_client.get_object(bucket: BUCKET, key: file, response_target: new_file)
      puts "Done"
    else
      puts "usage: n3 get [filename]"
    end
  when "put"
    if filename = arguments.first
      object_key = File.basename(filename)
      upload_response = $n3_aws_client.create_multipart_upload(bucket: BUCKET, key: object_key, acl: "public-read")
      multipart_upload = { parts: [] }

      File.open(filename) do |file|
        part_number = 1
        buffer_size = file.size > 5242880 ? 5242880 : file.size
        puts "File: #{File.basename(filename)}"
        puts "Size: #{file.size} bytes"
        puts "Buffer size: #{buffer_size} bytes"

        progress = ProgressBar.create(format: "%e %p% %b", starting_at: 0, total: file.size / buffer_size)

        until file.eof?
          buffer = file.read(buffer_size)
          resp = $n3_aws_client.upload_part({
            body: buffer,
            bucket: BUCKET,
            key: object_key,
            part_number: part_number,
            upload_id: upload_response.upload_id
          })
          multipart_upload[:parts] << {
            part_number: part_number,
            etag: resp.etag
          }
          part_number += 1
          progress.increment unless progress.finished?
        end

        puts "Done"
        progress.finish
      end

      $n3_aws_client.complete_multipart_upload({
        bucket: BUCKET,
        key: object_key,
        multipart_upload: multipart_upload,
        upload_id: upload_response.upload_id,
      })

      puts "Saved as: #{object_key}"
    else
      puts "usage: n3 put [filename]"
    end
  when "list"
    objs = $n3_aws_client.list_objects(bucket: BUCKET).contents.map(&:key)
    if objs.empty?
      puts "There is no stuff."
    else
      objs.each do |obj|
        puts obj
      end
    end
  when "delete"
    if file = arguments.first
      puts "Deleting #{file}"
      $n3_aws_client.delete_object(bucket: BUCKET, key: file)
      puts "Done"
    else
      puts "usage: n3 delete [filename]"
    end
  when "open"
    if file = arguments.first
      url = "http://#{BUCKET}.s3.amazonaws.com/#{file}"
      system("open #{url}")
    else
      puts "usage: n3 open [filename]"
    end
  when "help"
    puts USAGE_TEXT
  else
    puts USAGE_TEXT
  end
end