Email ETL Test | Python Fiddle

#!/env/bin/bash python
from __future__ import print_function

import json, re, urllib2
from collections import Counter
from sets import Set

print('Loading function')

def lambda_handler(event, context):
	# extract phase, also make sure environment is sane
	requester_email = event['email']
	if not requester_email: return 'Error: email field missing'

r = urllib2.urlopen(event['URL'])
	j = None
	try:
		j = json.load(r)['data']
	except Exception, e:
		return 'Error: data not found'

# transform phase
	# define schema, this might be swapped for a schema call to SwaggerUI
	transformedData = {
		"april_emails": [
			"string"
		],
		"your_email": "string",
		"unique_emails": [
			"string"
		],
		"user_domain_counts": [
			{
				"domain": 0
			}
		]
	}

# define some temporary vars
	domain_re = re.compile(ur'@([\w]+[\w.]+[\w]+)')
	domain_count = Counter()
	unique_emails = Set()
	april_emails = Set()

# only loop once, needs to be o^n complexity
	for n in j:
		if not n['email'] : continue # skip if email is missing
		email = str(n['email']).strip().lower() # normalize the data
		matchedDomain = re.search(domain_re, email)
		if matchedDomain: domain_count[matchedDomain.group()[1:]] += 1
		if email: unique_emails.add(email)
		if not n['login_date'] : continue
		if int(n['login_date'].split('-')[1]) == 4: april_emails.add(email)

# load phase
	# load the temp vars into the schema
	transformedData['your_email'] = event['email']
	transformedData['unique_emails'] = list(unique_emails)
	transformedData['user_domain_counts'] = [{d:domain_count[d]} for d in domain_count if domain_count[d] > 1] # don't count if it's only 1
 	transformedData['april_emails'] = list(april_emails)

# do some logging
	print(transformedData)

# save/respond with data
	return transformedData

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