Class: OCI::ObjectStorage::Transfer::Multipart::Internal::StdinPartIOWrapper

Inherits:
Object
  • Object
show all
Defined in:
lib/oci/object_storage/transfer/multipart/internal/stdin_part_io_wrapper.rb

Overview

A class which wraps standard input ($stdin) so that, for example, piped input can participate in multipart uploads. Standard input is not seekable so we need a special class to handle it rather than using SeekableNonFilePartIOWrapper.

This class can also vend data for each part to upload as part of a multipart upload. However, since we may not know the full size of $stdin beforehand, in addition to vending data this wrapper will also vend the part number to assign to the uploaded part.

Reading data out of stdin is synchronised so that only a single thread can read at any one time. This prevents issues where we could write the same part multiple times or write inconsistent data.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(source:) ⇒ StdinPartIOWrapper

Creates a new StdinPartIOWrapper

Parameters:

  • source (IO) —

    A reference to $stdin



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# File 'lib/oci/object_storage/transfer/multipart/internal/stdin_part_io_wrapper.rb', line 27

def initialize(source:)
  @source = source
  @lock = Mutex.new
  @part_number = 0
end

Instance Attribute Details

#source ⇒ IO (readonly)

A reference to $stdin

Returns:

  • (IO) 


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# File 'lib/oci/object_storage/transfer/multipart/internal/stdin_part_io_wrapper.rb', line 22

def source
  @source
end

Instance Method Details

#read(part_size) ⇒ Hash

Reads bytes from $stdin. This is synchronised so that only a single thread can perform this operation at any one time.

and the :part_number key will contain the part number we will assign to the part when we upload it as part of a multipart upload. If there is no more data from $stdin then this method will return nil.

Parameters:

  • part_size (Integer) —

    The number of bytes to read from $stdin

Returns:

  • (Hash) —

    A hash with two keys. The :content key will contain the content we read from $stdin



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# File 'lib/oci/object_storage/transfer/multipart/internal/stdin_part_io_wrapper.rb', line 41

def read(part_size)
  @lock.synchronize do
    read_content = @source.read(part_size)
    if read_content
      @part_number += 1
      { content: read_content, part_number: @part_number }
    end
  end
end