class Rack::RewindableInput
Class which can make any IO object rewindable, including non-rewindable ones. It does this by buffering the data into a tempfile, which is rewindable.
Don’t forget to call close
when you’re done. This frees up temporary resources that RewindableInput
uses, though it does not close the original IO object.
Public Class Methods
new(io)
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# File lib/rack/rewindable_input.rb, line 28 def initialize(io) @io = io @rewindable_io = nil @unlinked = false end
Public Instance Methods
close()
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Closes this RewindableInput
object without closing the originally wrapped IO object. Cleans up any temporary resources that this RewindableInput
has created.
This method may be called multiple times. It does nothing on subsequent calls.
# File lib/rack/rewindable_input.rb, line 64 def close if @rewindable_io if @unlinked @rewindable_io.close else @rewindable_io.close! end @rewindable_io = nil end end
each(&block)
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# File lib/rack/rewindable_input.rb, line 44 def each(&block) make_rewindable unless @rewindable_io @rewindable_io.each(&block) end
gets()
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# File lib/rack/rewindable_input.rb, line 34 def gets make_rewindable unless @rewindable_io @rewindable_io.gets end
read(*args)
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# File lib/rack/rewindable_input.rb, line 39 def read(*args) make_rewindable unless @rewindable_io @rewindable_io.read(*args) end
rewind()
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# File lib/rack/rewindable_input.rb, line 49 def rewind make_rewindable unless @rewindable_io @rewindable_io.rewind end
size()
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# File lib/rack/rewindable_input.rb, line 54 def size make_rewindable unless @rewindable_io @rewindable_io.size end
Private Instance Methods
filesystem_has_posix_semantics?()
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# File lib/rack/rewindable_input.rb, line 108 def filesystem_has_posix_semantics? RUBY_PLATFORM !~ /(mswin|mingw|cygwin|java)/ end
make_rewindable()
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# File lib/rack/rewindable_input.rb, line 77 def make_rewindable # Buffer all data into a tempfile. Since this tempfile is private to this # RewindableInput object, we chmod it so that nobody else can read or write # it. On POSIX filesystems we also unlink the file so that it doesn't # even have a file entry on the filesystem anymore, though we can still # access it because we have the file handle open. @rewindable_io = Tempfile.new('RackRewindableInput') @rewindable_io.chmod(0000) @rewindable_io.set_encoding(Encoding::BINARY) @rewindable_io.binmode # :nocov: if filesystem_has_posix_semantics? raise 'Unlink failed. IO closed.' if @rewindable_io.closed? @unlinked = true end # :nocov: buffer = "".dup while @io.read(1024 * 4, buffer) entire_buffer_written_out = false while !entire_buffer_written_out written = @rewindable_io.write(buffer) entire_buffer_written_out = written == buffer.bytesize if !entire_buffer_written_out buffer.slice!(0 .. written - 1) end end end @rewindable_io.rewind end