Sync tasks assigned to you in an Asana workspace to an area in Things 3. Define variables for lines 20 and 21 in a "data.yml" file. Fill in your area name on line 22.

asana_to_things.rb

#!/usr/bin/env ruby
# Syncing Tasks Assigned to you in Asana with Things 3
 
require 'json'
require 'yaml/store'
require 'time'

# Load storage file and variables
store = YAML::Store.new("data.yml")
mod = store.transaction { store[:mod_time] }
if mod == nil
	mod = Time.now.utc.iso8601
end
existing = store.transaction { store[:asana_ids] }
if existing == nil
	existing = []
end

# Load Asana variables and Things area
asana_token = store.transaction { store[:asana_token] }
workspace = store.transaction { store[:asana_workspace] }
area = "YOUR AREA NAME"

# Find and close completed tasks
completed = %x{ osascript <<APPLESCRIPT
	tell application "Things3"
	set output to ""
	repeat with toDo in (to dos whose status is completed) of area "#{area}"
		set theID to notes of toDo
		set output to output & theID & ","
	end repeat
	return output
end tell
APPLESCRIPT}

completed = completed.strip

if completed != ""
	completed = completed.chomp(",").split(",")
	completed.each do |id|
		`curl -s --request PUT -H "Authorization: Bearer #{asana_token}" https://app.asana.com/api/1.0/tasks/#{id} --data-urlencode "completed=true"`
	end
	`osascript -e 'Tell application "Things3" to log completed now'`
else
	puts "Nothing doing!"
end
 
# Get new uncompleted tasks from Asana, create them if they don't already exist
tasks = `curl -s -H "Authorization: Bearer #{asana_token}" "https://app.asana.com/api/1.0/tasks?workspace=#{workspace}&assignee=me&modified_since=#{mod}&completed_since=now"`
data = JSON.parse(tasks)
if data["data"].empty? == true
	puts "No changes!"
else
	existing = store.transaction { store[:asana_ids] }
	data["data"].each do |task|
	    name = task["name"]
	    id = task["id"].to_s
    	if existing.include?(id) == false
		    %x{ osascript <<APPLESCRIPT
				tell application "Things3"
					set newToDo to make new to do ¬
						with properties {name:"#{name}", notes:"#{id}"} at beginning of area "#{area}"
				end tell
			APPLESCRIPT}
			store.transaction do
				store[:asana_ids].push(id)
			end
			puts "#{name} created!"
		else
			puts "#{name} already present!"
		end
	end
end

store.transaction do
  store[:mod_time] = Time.now.utc.iso8601
end