Remote File Pattern with Checksum Validation

_install_from_source.rb

url          = node['redisio']['mirror']
base_name    = node['redisio']['base_name']
version      = node['redisio']['version']
extension    = node['redisio']['artifact_type']

tarball_name = "#{base_name}#{version}"
tarball      = "#{tarball_name}.#{extension}"
download_url = "#{url}/#{tarball}"

download_dir = node['redisio']['download_dir']
sha256_checksum = node['redisio']['sha256_checksum']

# Install from source
remote_file "Download Redis Source" do
  path "#{download_dir}/#{tarball}"
  source download_url
  backup false
  checksum sha256_checksum
  notifies :create, "ruby_block[Validate Tarball Checksum]", :immediately
  not_if { redis_exists? && node['redisio']['safe_install'] }
end

ruby_block "Validate Tarball Checksum" do
  action :nothing
  block do
    require 'digest'
    checksum = Digest::SHA1.file("#{download_dir}/#{tarball}").hexdigest
    Chef::Log.debug("Computed Tarball Checksum: #{checksum}")
    Chef::Log.debug("Expected Tarball Checksum: #{node['redisio']['sha1_checksum']}")
    if checksum != node['redisio']['sha1_checksum'] 
      raise "Downloaded Tarball Checksum #{checksum} does not match known checksum #{node['redisio']['sha1_checksum']}"
    end
  end
  notifies :run, "execute[Unpack Redis Tarball]", :immediately
end

execute "Unpack Redis Tarball" do
  command "tar -xvzf #{tarball}"
  action :nothing
  cwd download_dir
  notifies :run, "execute[Make Redis]", :immediately
end