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