Class: Bundler::CompactIndexClient::Updater

Inherits:
Object
  • Object
show all
Defined in:
lib/bundler/compact_index_client/updater.rb

Defined Under Namespace

Classes: MisMatchedChecksumError

Instance Method Summary collapse

Constructor Details

#initialize(fetcher) ⇒ Updater

Returns a new instance of Updater.



21
22
23
 
# File 'lib/bundler/compact_index_client/updater.rb', line 21

def initialize(fetcher)
  @fetcher = fetcher
end

Instance Method Details

#checksum_for_file(path) ⇒ Object 



92
93
94
95
96
97
98
99
100
 
# File 'lib/bundler/compact_index_client/updater.rb', line 92

def checksum_for_file(path)
  return nil unless path.file?
  # This must use File.read instead of Digest.file().hexdigest
  # because we need to preserve \n line endings on windows when calculating
  # the checksum
  SharedHelpers.filesystem_access(path, :read) do
    SharedHelpers.digest(:MD5).hexdigest(File.read(path))
  end
end

#etag_for(path) ⇒ Object 



83
84
85
86
 
# File 'lib/bundler/compact_index_client/updater.rb', line 83

def etag_for(path)
  sum = checksum_for_file(path)
  sum ? %("#{sum}") : nil
end

#slice_body(body, range) ⇒ Object 



88
89
90
 
# File 'lib/bundler/compact_index_client/updater.rb', line 88

def slice_body(body, range)
  body.byteslice(range)
end

#update(local_path, remote_path, retrying = nil) ⇒ Object 



25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
 
# File 'lib/bundler/compact_index_client/updater.rb', line 25

def update(local_path, remote_path, retrying = nil)
  headers = {}

  local_temp_path = local_path.sub(/$/, ".#{$$}")
  local_temp_path = local_temp_path.sub(/$/, ".retrying") if retrying
  local_temp_path = local_temp_path.sub(/$/, ".tmp")

  # first try to fetch any new bytes on the existing file
  if retrying.nil? && local_path.file?
    copy_file local_path, local_temp_path

    headers["If-None-Match"] = etag_for(local_temp_path)
    headers["Range"] =
      if local_temp_path.size.nonzero?
        # Subtract a byte to ensure the range won't be empty.
        # Avoids 416 (Range Not Satisfiable) responses.
        "bytes=#{local_temp_path.size - 1}-"
      else
        "bytes=#{local_temp_path.size}-"
      end
  end

  response = @fetcher.call(remote_path, headers)
  return nil if response.is_a?(Net::HTTPNotModified)

  content = response.body

  etag = (response["ETag"] || "").gsub(%r{\AW/}, "")
  correct_response = SharedHelpers.filesystem_access(local_temp_path) do
    if response.is_a?(Net::HTTPPartialContent) && local_temp_path.size.nonzero?
      local_temp_path.open("a") {|f| f << slice_body(content, 1..-1) }

      etag_for(local_temp_path) == etag
    else
      local_temp_path.open("wb") {|f| f << content }

      etag.length.zero? || etag_for(local_temp_path) == etag
    end
  end

  if correct_response
    SharedHelpers.filesystem_access(local_path) do
      FileUtils.mv(local_temp_path, local_path)
    end
    return nil
  end

  if retrying
    raise MisMatchedChecksumError.new(remote_path, etag, etag_for(local_temp_path))
  end

  update(local_path, remote_path, :retrying)
rescue Zlib::GzipFile::Error
  raise Bundler::HTTPError
ensure
  FileUtils.remove_file(local_temp_path) if File.exist?(local_temp_path)
end