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@twslankard
Created Apr 2, 2013
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Ruby S3 multi-part uploader with resume capability. Usage: ruby mpu.rb [file to upload] [bucket] [key] My knowledge of Ruby isn't great, so I offer my apologies for the bad code.
#!/usr/bin/env ruby
require 'rubygems'
require 'aws-sdk'
def readPart(file_name, file_size, part_size, part)
file_offset = part_size * ( part - 1 )
bytes_to_read = [ part_size, file_size - file_offset ].min
part_contents = File.read( file_name, bytes_to_read, file_offset )
part_md5 = Digest::MD5.hexdigest( part_contents )
return part_contents, part_md5
end
def uploadPart(part_contents, part_md5, part, upload)
result_obj = upload.add_part( part_contents, :part_number => part )
etag_md5sum = result_obj.etag[ 1..-2 ] # strip off the quotes ... not sure why they decided to include those
if etag_md5sum != part_md5
raise "part_md5 mismatch!"
end
end
def shouldUploadPart(part, part_md5, upload)
begin
if upload.parts[part].etag[1..-2] == part_md5
return false
end
rescue
return true
end
return true
end
def uploadPartWithRetry(part_contents, part_md5, part, upload, tries)
the_exception = nil
for try in 1..tries
begin
uploadPart(part_contents, part_md5, part, upload)
return
rescue => e
the_exception = e
end
end
raise "too many retries, error: " + the_exception.message
end
def uploadParts(file_name, file_size, part_size, number_of_parts, upload)
skipped_parts = 0
start_time = Time.now
for part in 1..number_of_parts
part_contents, part_md5 = readPart( file_name, file_size, part_size, part )
if( shouldUploadPart( part, part_md5, upload ) )
uploadPartWithRetry(part_contents, part_md5, part, upload, 3)
elapsed_time = Time.now - start_time
average_part_time = elapsed_time / (part - skipped_parts)
estimated_time_remaining = (average_part_time * (number_of_parts - part) / 60.0).ceil
puts "Uploaded #{part}/#{number_of_parts} parts. Estimated time remaining: #{estimated_time_remaining} minutes"
else
skipped_parts += 1
puts "Skipping already uploaded part #{part}/#{number_of_parts}."
end
end
upload.complete(:remote_parts)
end
file_name = ARGV[0]
bucket_name = ARGV[1]
key_name = ARGV[2]
s3 = AWS::S3.new
bucket = s3.buckets[bucket_name]
object = bucket.objects[key_name]
number_of_multipart_uploads = 0
object.multipart_uploads.each do |upload|
number_of_multipart_uploads += 1
end
upload = nil
if number_of_multipart_uploads > 1
raise "multiple uploads in progress" # haven't decided what to do here yet
elsif number_of_multipart_uploads == 1
upload = object.multipart_uploads.first
else
upload = object.multipart_upload
end
file_size = File.size(file_name)
part_size = [ (file_size / 10000.0).ceil, 5*1024*1024 ].max
number_of_parts = (file_size / part_size.to_f).ceil
puts "Uploading #{file_size} byte file as #{number_of_parts} chunks each up to #{part_size} bytes."
uploadParts(file_name, file_size, part_size, number_of_parts, upload)
puts "Done!"
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