Class: N::App::ScriptHandler

Inherits:
Handler show all
Defined in:
lib/n/app/handlers.rb

Overview

Script Handler

Base handler for scripts.

Direct Known Subclasses

CodeHandler, PageHandler

Constant Summary collapse

@@compiled_script_cache =

cache the compiled page scripts to optimize future references. use a thread safe cache.

N::SafeHash.new()
@@compile_sync =

dont allow 2 threads to compile the same script. In fact dont allow two threads to compile in parallel.

Sync.new

Instance Attribute Summary

Attributes inherited from ServerFilter

#next_filter

Instance Method Summary collapse

Methods inherited from Handler

#process

Methods inherited from ServerFilter

#<<, #initialize, #process, #process_next

Constructor Details

This class inherits a constructor from N::ServerFilter

Instance Method Details

#compile_script(script) ⇒ Object

the compiler returns a singleton class customized for rendering the input script. The original idea was to define render() as a static method and return the class, but we will use a singleton object to keep custom data structures (sub-page-graph, metrics, etc)

script_path is used as key in the Dynamic class creation and for caching

Design:

we use __ for out too to avoid nasty collisions.



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# File 'lib/n/app/handlers.rb', line 79

def compile_script(script)
	compiled_script = nil
	
	# dont allow 2 threads to compile the same script. In fact dont 
	# allow two threads to compile in parallel.
	# gmosx: SOS this eval assigns the variable compiled_script!
	@@compile_sync.synchronize {
		eval(script)
	}
		
	return compiled_script		
end

#compiled_script_cache ⇒ Object 



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# File 'lib/n/app/handlers.rb', line 92

def compiled_script_cache
	return @@compiled_script_cache
end

#log_error(request, ex) ⇒ Object

Log a rendering error

Raises:



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# File 'lib/n/app/handlers.rb', line 98

def log_error(request, ex)
	request.log_error "--------"
	request.log_error "#{request.path}:"
	request.log_error "#{ex.class}: #{ex}"
	request.log_error ex.backtrace()
	raise ScriptHandlerError.new(0, "error")
end

#overload_path(path) ⇒ Object

Overload the path. FIXME: better name and much better documentation.



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# File 'lib/n/app/handlers.rb', line 57

def	overload_path(path)
	path.gsub!(/\/\//, '/')
	
	if ::File.exists?("#$root_dir/#{path}")
		return path
	else
		$log.debug "OVERLOAD: '#{path}' -> 'p/#{path}'" if $DBG
		return "p/#{path}"
	end		
end