1 # -*- encoding: binary -*-
2 # internal implementation details here, do not rely on them in your code
4 # This class is needed because Net::HTTP streaming is still inefficient
5 # for reading huge response bodies over fast LANs.
6 class MogileFS::HTTPReader < MogileFS::Socket
7 attr_accessor :content_length, :uri
9 # backwards compat, if anybody cares
10 alias mogilefs_size content_length # :nodoc:
12 # this may OOM your system on large files
15 read(@content_length, buf)
16 return buf if buf.size == @content_length
18 raise MogileFS::SizeMismatchError,
19 "read=#{buf.size} bytes, expected=#@content_length from #@uri", []
23 rv = MogileFS.io.copy_stream(self, dest)
24 return rv if rv == @content_length
25 raise MogileFS::SizeMismatchError,
26 "read=#{rv} bytes, expected=#@content_length from #@uri", []
29 def self.first(paths, timeout, range = nil)
31 range = "Range: bytes=#{range[0]}-#{range[1]}\r\n" if range
35 sock = try(path, timeout, range) and return sock
38 errors << "#{path} - #{e.message} (#{e.class})"
41 raise MogileFS::Error,
42 "all paths failed with GET: #{errors.join(', ')}", []
45 # given a path, this returns a readable socket with ready data from the
46 # body of the response.
47 def self.try(path, timeout, range) # :nodoc:
49 expire_at = MogileFS.now + timeout
50 sock = tcp(uri.host, uri.port, timeout)
51 buf = "GET #{uri.request_uri} HTTP/1.0\r\n#{range}\r\n" # no chunking
52 sock.timed_write(buf, timeout)
55 raise MogileFS::Timeout if MogileFS.now > expire_at
56 sock.timed_peek(2048, buf, timeout) or
57 raise MogileFS::InvalidResponseError, "EOF while reading header", []
58 end until /\r\n\r\n/ =~ buf
60 head, _ = buf.split(/\r\n\r\n/, 2)
61 if ((range && head =~ %r{\AHTTP/\d+\.\d+\s+206\s*}) ||
62 (!range && head =~ %r{\AHTTP/\d+\.\d+\s+200\s*})) &&
63 head =~ %r{^Content-Length:\s*(\d+)}i
64 sock.content_length = $1.to_i
66 sock.timed_read(head.bytesize + 4, buf, 0)
69 msg = range ? "Expected 206 w/#{range.strip}: " : "header="
71 raise MogileFS::InvalidResponseError, msg, []