Class: Relaxo::QueryServer::ListRenderer

Inherits:
Process
  • Object
show all
Defined in:
lib/relaxo/query_server/designer.rb

Overview

Supports the ‘list` action which consumes rows and outputs encoded text in chunks.

Instance Method Summary collapse

Methods inherited from Process

#call, #log

Constructor Details

#initialize(context, function) ⇒ ListRenderer

Returns a new instance of ListRenderer.



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# File 'lib/relaxo/query_server/designer.rb', line 59

def initialize(context, function)
	super(context, function)
	
	@started = false
	@fetched_row = false
	@start_response = {:headers => {}}
	@chunks = []
end

Instance Method Details

#each ⇒ Object 



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# File 'lib/relaxo/query_server/designer.rb', line 82

def each
	while row = get_row
		yield row
	end
end

#flush ⇒ Object 



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# File 'lib/relaxo/query_server/designer.rb', line 110

def flush
	if @started
		@context.shell.write_object ["chunks", @chunks]
	else
		@context.shell.write_object ["start", @chunks, @start_response]
		
		@started = true
	end
	
	@chunks = []
end

#get_row ⇒ Object 



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# File 'lib/relaxo/query_server/designer.rb', line 88

def get_row
	flush
	
	row = @context.shell.read_object
	@fetched_row = true
	
	case command = row[0]
	when "list_row"
		row[1]
	when "list_end"
		false
	else
		raise RuntimeError.new("Input is not a row!")
	end
end

#run(head, request) ⇒ Object 



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# File 'lib/relaxo/query_server/designer.rb', line 68

def run(head, request)
	super(head, request)
	
	# Ensure that at least one row is read from input:
	get_row unless @fetched_row
	
	return ["end", @chunks]
end

#send(chunk) ⇒ Object 



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# File 'lib/relaxo/query_server/designer.rb', line 77

def send(chunk)
	@chunks << chunk
	false
end

#start(response) ⇒ Object

Raises:

  • (RuntimeError) 


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# File 'lib/relaxo/query_server/designer.rb', line 104

def start(response)
	raise RuntimeError.new("List already started!") if @started
	
	@start_response = response
end