A Decorator for ArcGIS Python toolbox tools (their execute function) that makes the "parameters" parameter into a dictionary indexed by parameter name

python_toolbox_parameters_as_dict.py

"""
	A Decorator for ArcGIS Python toolbox tools (their execute function) that makes the "parameters" parameter'
	into a dictionary indexed by parameter name.
"""

from functools import wraps

def parameters_as_dict(f):
	@wraps(f)
	def wrapper(*args, **kwargs):
		params = args[1]
		parameters = {}
		for param in params:
			parameters[param.name] = param

		f(self=args[0], parameters=parameters, messages=args[1])

	return wrapper

############################
# EXAMPLE USAGE FOLLOWS
############################

	
class GenerateHeatPlot(object):
# Incomplete tool definition for example - pay attention to use of decorator around execute method.

	def getParameterInfo(self):

		code = arcpy.Parameter(
			displayName="Code for Transect",
			name="site_code",
		)

		wq_var = arcpy.Parameter(
			displayName="Water Quality Variable",
			name="wq_var",
		)

		title = arcpy.Parameter(
			displayName="Title for graph",
			name="output_title",
		)

		output_folder = arcpy.Parameter(
			displayName="Output folder",
			name="output_folder",
		)

		params = [code, wq_var, title, output_folder]
		return params

	### ... rest of your toolbox definition code here.

	@parameters_as_dict
	def execute(self, parameters, messages):

		site_code = parameters["site_code"].valueAsText
		wq_var = parameters["wq_var"].valueAsText
		title = parameters["output_title"].valueAsText
		output_folder = parameters["output_folder"].valueAsText