d7f3561949
If the image download fails, the temp file is left behind, which breaks the idempotency of the image download. This commit adds a cleanup step to remove the temp file if the download fails.
94 lines
2.7 KiB
Ruby
94 lines
2.7 KiB
Ruby
# frozen_string_literal: true
|
|
|
|
require "digest"
|
|
require "fileutils"
|
|
require "uri"
|
|
require_relative "../../common/lib/arch"
|
|
|
|
class BootImage
|
|
def initialize(name, version)
|
|
@name = name
|
|
@version = version
|
|
end
|
|
|
|
def image_path
|
|
# YYY: Support for unversioned images is still required in StorageVolume
|
|
# code when we want to recreate storage. We can remove this check once we
|
|
# have removed all unversioned images from production.
|
|
@image_path ||= if @version.nil?
|
|
"#{image_root}/#{@name}.raw"
|
|
else
|
|
"#{image_root}/#{@name}-#{@version}.raw"
|
|
end
|
|
end
|
|
|
|
def image_root
|
|
"/var/storage/images"
|
|
end
|
|
|
|
def download(url:, ca_path: nil, sha256sum: nil)
|
|
return if File.exist?(image_path)
|
|
|
|
FileUtils.mkdir_p image_root
|
|
|
|
# If image URL has query parameter such as SAS token, File.extname returns
|
|
# it too. We need to remove them and only get extension.
|
|
ext = image_ext(url)
|
|
init_format = initial_format(ext)
|
|
|
|
# Use of File::EXCL provokes a crash rather than a race
|
|
# condition if two VMs are lazily getting their images at the
|
|
# same time.
|
|
temp_file_name = @version.nil? ? @name : "#{@name}-#{@version}"
|
|
temp_path = File.join(image_root, "#{temp_file_name}#{ext}.tmp")
|
|
begin
|
|
file_sha256sum = curl_image(url, temp_path, ca_path)
|
|
verify_sha256sum(file_sha256sum, sha256sum)
|
|
convert_image(temp_path, init_format)
|
|
ensure
|
|
rm_if_exists(temp_path)
|
|
end
|
|
end
|
|
|
|
def image_ext(url)
|
|
File.extname(URI.parse(url).path)
|
|
end
|
|
|
|
def initial_format(ext)
|
|
case ext
|
|
when ".qcow2", ".img"
|
|
"qcow2"
|
|
when ".vhd"
|
|
"vpc"
|
|
when ".raw"
|
|
"raw"
|
|
else
|
|
fail "Unsupported boot_image format: #{ext}"
|
|
end
|
|
end
|
|
|
|
def curl_image(url, temp_path, ca_path)
|
|
ca_arg = ca_path ? " --cacert #{ca_path.shellescape}" : ""
|
|
sha256_sum = nil
|
|
File.open(temp_path, File::RDWR | File::CREAT | File::EXCL, 0o644) do
|
|
digest_out = r "bash -c 'curl -f -L10 #{url.shellescape}#{ca_arg} | tee >(openssl dgst -sha256) > #{temp_path.shellescape}'"
|
|
sha256_sum = digest_out.split(" ").last
|
|
end
|
|
sha256_sum
|
|
end
|
|
|
|
def verify_sha256sum(file_sha256sum, expected_sha256sum)
|
|
fail "Invalid SHA256 sum." if !expected_sha256sum.nil? && file_sha256sum != expected_sha256sum
|
|
end
|
|
|
|
def convert_image(temp_path, initial_format)
|
|
if initial_format == "raw"
|
|
File.rename(temp_path, image_path)
|
|
else
|
|
# Images are presumed to be atomically renamed into the path,
|
|
# i.e. no partial images will be passed to qemu-image.
|
|
r "qemu-img convert -p -f #{initial_format.shellescape} -O raw #{temp_path.shellescape} #{image_path.shellescape}"
|
|
end
|
|
end
|
|
end
|