sim_job

  1#!/usr/bin/ruby
  2# frozen_string_literal: true
  3
  4require "bigdecimal"
  5require "pg/em/connection_pool"
  6require "eventmachine"
  7require "em_promise"
  8require "em-hiredis"
  9require "dhall"
 10require "sentry-ruby"
 11
 12Sentry.init do |config|
 13	config.background_worker_threads = 0
 14end
 15
 16SCHEMA = "{
 17	xmpp: { jid: Text, password: Text },
 18	component: { jid: Text },
 19	keepgo: Optional { access_token: Text, api_key: Text },
 20	sims: {
 21		CAD: { per_gb: Natural, annual: Natural },
 22		USD: { per_gb: Natural, annual: Natural }
 23	},
 24	plans: List {
 25		currency: < CAD | USD >,
 26		messages: < limited: { included: Natural, price: Natural } | unlimited >,
 27		minutes: < limited: { included: Natural, price: Natural } | unlimited >,
 28		monthly_price : Natural,
 29		name : Text,
 30		allow_register: Bool
 31	}
 32}"
 33
 34raise "Need a Dhall config" unless ARGV[0]
 35
 36CONFIG = Dhall::Coder
 37	.new(safe: Dhall::Coder::JSON_LIKE + [Symbol, Proc])
 38	.load("#{ARGV.first} : #{SCHEMA}", transform_keys: :to_sym)
 39
 40CONFIG[:keep_area_codes_in] = {}
 41CONFIG[:creds] = {}
 42
 43require_relative "../lib/blather_notify"
 44require_relative "../lib/customer_repo"
 45require_relative "../lib/low_balance"
 46require_relative "../lib/postgres"
 47require_relative "../lib/sim_repo"
 48require_relative "../lib/transaction"
 49
 50CUSTOMER_REPO = CustomerRepo.new
 51SIM_REPO = SIMRepo.new
 52
 53class JobCustomer < SimpleDelegator
 54	def billing_customer
 55		super.then(&self.class.method(:new))
 56	end
 57
 58	def stanza_to(stanza)
 59		stanza = stanza.dup
 60		stanza.from = nil # It's a client connection, use default
 61		stanza.to = Blather::JID.new(
 62			"customer_#{customer_id}", CONFIG[:component][:jid]
 63		).with(resource: stanza.to&.resource)
 64		block_given? ? yield(stanza) : (BlatherNotify << stanza)
 65	end
 66end
 67
 68module SimAction
 69	attr_accessor :customer
 70
 71	def initialize(sim)
 72		@sim = sim
 73	end
 74
 75	def iccid
 76		@sim.iccid
 77	end
 78
 79	def customer_id
 80		customer.customer_id
 81	end
 82
 83	def refill_price
 84		(BigDecimal(CONFIG[:sims][customer.currency][:per_gb]) / 100) * 5
 85	end
 86
 87	def refill_and_bill(data, price, note)
 88		SIM_REPO.refill(@sim, amount_mb: data).then { |keepgo_tx|
 89			raise "SIM refill failed" unless keepgo_tx["ack"] == "success"
 90
 91			Transaction.new(
 92				customer_id: customer_id,
 93				transaction_id: keepgo_tx["transaction_id"],
 94				amount: -price, note: note
 95			).insert
 96		}.then do
 97			puts "Refilled #{customer.customer_id} #{iccid}"
 98		end
 99	end
100
101	def monthly_limit
102		REDIS.get(
103			"jmp_customer_monthly_data_limit-#{customer_id}"
104		).then do |limit|
105			BigDecimal(limit || refill_price)
106		end
107	end
108
109	def amount_spent
110		promise = DB.query_defer(<<~SQL, [customer_id])
111			SELECT COALESCE(SUM(amount), 0) AS a FROM transactions WHERE
112			customer_id=$1 AND transaction_id LIKE 'AB_59576_%' AND
113			created_at >= DATE_TRUNC('month', LOCALTIMESTAMP)
114		SQL
115		promise.then { |rows| rows.first["a"] }
116	end
117end
118
119class SimTopUp
120	include SimAction
121
122	def low_balance
123		LowBalance.for(customer, refill_price).then(&:notify!).then do |result|
124			next call if result.positive?
125
126			puts "Low balance #{customer.customer_id} #{iccid}"
127		end
128	end
129
130	def call
131		EMPromise.all([amount_spent, monthly_limit]).then do |(spent, limit)|
132			if spent < limit
133				next low_balance if customer.balance < refill_price
134
135				refill_and_bill(5120, refill_price, "5GB Data Topup for #{iccid}")
136			else
137				SimWarn.new(@sim).call
138			end
139		end
140	end
141end
142
143class SimWarn
144	include SimAction
145
146	def notify
147		m = Blather::Stanza::Message.new
148		m.body = "Your SIM #{iccid} only has " \
149		         "#{(@sim.remaining_usage_kb / 1024).to_i} MB left"
150		customer.stanza_to(m)
151	end
152
153	def call
154		EMPromise.all([amount_spent, monthly_limit]).then do |(spent, limit)|
155			next unless spent >= limit || low_balance_and_not_auto_top_up
156
157			notify
158			puts "Data warning #{customer.customer_id} #{sim.iccid}"
159		end
160	end
161
162	def low_balance_and_not_auto_top_up
163		customer.balance < refill_price && !customer.auto_top_up_amount&.positive?
164	end
165end
166
167class SimAnnual
168	include SimAction
169
170	def notify
171		m = Blather::Stanza::Message.new
172		m.body = "Your SIM #{iccid} only has #{@sim.remaining_days} days left"
173		customer.stanza_to(m)
174	end
175
176	def annual_price
177		BigDecimal(CONFIG[:sims][customer.currency][:annual]) / 100
178	end
179
180	def call
181		if customer.balance >= annual_fee
182			refill_and_bill(1024, annual_price, "Annual fee for #{iccid}")
183		else
184			LowBalance.for(customer, refill_price).then(&:notify!).then do |result|
185				next call if result.positive?
186
187				notify
188			end
189		end
190	end
191
192	def annual_fee
193		customer.currency == :USD ? BigDecimal("5.50") : BigDecimal("7.50")
194	end
195end
196
197def fetch_customers(cids)
198	# This is gross N+1 against the DB, but also does a buch of Redis work
199	# We expect the set to be very small for the forseeable future,
200	# hundreds at most
201	EMPromise.all(
202		Set.new(cids).to_a.compact.map { |id| CUSTOMER_REPO.find(id) }
203	).then do |customers|
204		Hash[customers.map { |c| [c.customer_id, JobCustomer.new(c)] }]
205	end
206end
207
208SIM_QUERY = "SELECT iccid, customer_id FROM sims WHERE iccid = ANY ($1)"
209def load_customers!(sims)
210	DB.query_defer(SIM_QUERY, [sims.keys]).then { |rows|
211		fetch_customers(rows.map { |row| row["customer_id"] }).then do |customers|
212			rows.each do |row|
213				sims[row["iccid"]]&.customer = customers[row["customer_id"]]
214			end
215
216			sims
217		end
218	}
219end
220
221def decide_sim_actions(sims)
222	sims.each_with_object({}) { |sim, h|
223		if sim.remaining_usage_kb < 100000
224			h[sim.iccid] = SimTopUp.new(sim)
225		elsif sim.remaining_usage_kb < 250000
226			h[sim.iccid] = SimWarn.new(sim)
227		elsif sim.remaining_days < 30
228			h[sim.iccid] = SimAnnual.new(sim)
229		end
230	}.compact
231end
232
233EM.run do
234	REDIS = EM::Hiredis.connect
235	DB = Postgres.connect(dbname: "jmp")
236
237	BlatherNotify.start(
238		CONFIG[:xmpp][:jid],
239		CONFIG[:xmpp][:password]
240	).then { SIM_REPO.all }.then { |sims|
241		load_customers!(decide_sim_actions(sims))
242	}.then { |items|
243		items = items.values.select(&:customer)
244		EMPromise.all(items.map(&:call))
245	}.catch { |e|
246		p e
247
248		if e.is_a?(::Exception)
249			Sentry.capture_exception(e)
250		else
251			Sentry.capture_message(e.to_s)
252		end
253	}.then { EM.stop }
254end