Class: Protocol::Multipart::FormData::Parser

Inherits:
Object
  • Object
show all
Defined in:
lib/protocol/multipart/form_data/parser.rb

Overview

A configurable parser for multipart/form-data bodies.

Constant Summary collapse

CONTENT_TYPE = 
"multipart/form-data"

Instance Method Summary collapse

Constructor Details

#initialize(maximum_field_size: MAXIMUM_FIELD_SIZE, maximum_upload_size: MAXIMUM_UPLOAD_SIZE, maximum_total_size: MAXIMUM_TOTAL_SIZE, maximum_depth: Protocol::URL::FormData::Nested::MAXIMUM_DEPTH, **options) ⇒ Parser

Initialize the form data parser.



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# File 'lib/protocol/multipart/form_data/parser.rb', line 23

def initialize(maximum_field_size: MAXIMUM_FIELD_SIZE, maximum_upload_size: MAXIMUM_UPLOAD_SIZE, maximum_total_size: MAXIMUM_TOTAL_SIZE, maximum_depth: Protocol::URL::FormData::Nested::MAXIMUM_DEPTH, **options)
	if maximum_depth and maximum_depth < 0
		raise ArgumentError, "Form data limits must be non-negative!"
	end
	
	@maximum_field_size = maximum_field_size
	@maximum_upload_size = maximum_upload_size
	@maximum_total_size = maximum_total_size
	@maximum_depth = maximum_depth
	@options = options
end

Instance Method Details

#each(readable, boundary:) ⇒ Object

Incrementally enumerate multipart form data.

Fields are yielded as strings. File uploads are yielded as streaming Upload instances and are only readable during the corresponding block invocation.



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# File 'lib/protocol/multipart/form_data/parser.rb', line 66

def each(readable, boundary:)
	return to_enum(__method__, readable, boundary:) unless block_given?
	
	total_limit = ByteLimit.new(@maximum_total_size, name: :total_size)
	parser = Multipart::Parser.new(readable, boundary, **@options)
	
	parser.each do |part|
		disposition = part.headers["content-disposition"]
		
		unless disposition&.type == "form-data" and name = disposition["name"]
			raise ArgumentError, "Multipart form part is missing a form-data name!"
		end
		
		if filename = disposition["filename"]
			upload = Upload.new(part, filename, @maximum_upload_size, total_limit)
			yield name, upload
			upload.discard
		else
			field_limit = ByteLimit.new(@maximum_field_size, name: :field_size)
			value = String.new.b
			
			part.each do |chunk|
				field_limit.consume(chunk.bytesize)
				total_limit.consume(chunk.bytesize)
				value << chunk
			end
			
			yield name, value
		end
	end
end

#parse(readable, result = make_result, boundary:) ⇒ Object

Parse multipart form data into a nested hash.

When a block is given, each value is passed through the block before assignment. The value returned by the block is assigned to the result. Uploads require a block because they must be consumed before parsing advances to the next part.



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# File 'lib/protocol/multipart/form_data/parser.rb', line 44

def parse(readable, result = make_result, boundary:)
	each(readable, boundary:) do |name, value|
		if block_given?
			value = yield(name, value)
		elsif value.is_a?(Upload)
			raise ArgumentError, "A block is required to consume file uploads!"
		end
		
		result.add(name, value)
	end
	
	return result.to_h
end