Basic caching of running balances

About 60% performance improvement on balance report

austax/__init__.py

@@ -79,8 +79,7 @@ def make_tax_transactions():
 		))
 	
 	# Get trial balance
-	balancer = TrialBalancer()
+	balancer = TrialBalancer.from_cached()
-	balancer.apply_transactions(db.session.scalars(db.select(Transaction).options(db.selectinload(Transaction.postings))).all())
 	
 	accounts = dict(sorted(balancer.accounts.items()))
 	

austax/reports.py

@@ -84,8 +84,7 @@ def study_loan_repayment(year, taxable_income, rfb_grossedup):
 @assert_aud
 def tax_summary_report():
 	# Get trial balance
-	balancer = TrialBalancer()
+	balancer = TrialBalancer.from_cached(start_date=sofy_date(), end_date=eofy_date())
-	balancer.apply_transactions(db.session.scalars(db.select(Transaction).where((Transaction.dt >= sofy_date()) & (Transaction.dt <= eofy_date())).options(db.selectinload(Transaction.postings))).all())
 	
 	accounts = dict(sorted(balancer.accounts.items()))
 	

drcr/models.py

@@ -64,6 +64,10 @@ class Posting(db.Model):
 	quantity = db.Column(db.Integer)
 	commodity = db.Column(db.String)
 	
+	# Running balance of the account in units of reporting_commodity
+	# Only takes into consideration Transactions stored in database, not API-generated ones
+	running_balance = db.Column(db.Integer)
+	
 	transaction = db.relationship('Transaction', back_populates='postings')
 	
 	def __init__(self, description=None, account=None, quantity=None, commodity=None):
@@ -196,13 +200,83 @@ class TrialBalancer:
 	def __init__(self):
 		self.accounts = {}
 	
+	@classmethod
+	def from_cached(cls, start_date=None, end_date=None):
+		"""Obtain a TrialBalancer based on the cached running_balance"""
+		
+		if start_date is not None:
+			result_start_date = cls()
+			
+			# First SELECT the last applicable dt by account
+			# Then, among the transactions with that dt, SELECT the last applicable transaction_id
+			# Then extract the running_balance for each account at that transaction_id
+			running_balances = db.session.execute('''
+				SELECT p3.account, running_balance FROM
+				(
+					SELECT p1.account, max(p2.transaction_id) AS max_tid FROM
+					(
+						SELECT account, max(dt) AS max_dt FROM postings JOIN transactions ON postings.transaction_id = transactions.id WHERE dt < :start_date GROUP BY account
+					) p1
+					JOIN postings p2 ON p1.account = p2.account AND p1.max_dt = transactions.dt JOIN transactions ON p2.transaction_id = transactions.id GROUP BY p2.account
+				) p3
+				JOIN postings p4 ON p3.account = p4.account AND p3.max_tid = p4.transaction_id
+			''', {'start_date': start_date})
+			
+			for running_balance in running_balances.all():
+				result_start_date.accounts[running_balance.account] = Amount(running_balance.running_balance, reporting_commodity())
+		
+		if end_date is None:
+			result = cls()
+			
+			running_balances = db.session.execute('''
+				SELECT p3.account, running_balance FROM
+				(
+					SELECT p1.account, max(p2.transaction_id) AS max_tid FROM
+					(
+						SELECT account, max(dt) AS max_dt FROM postings JOIN transactions ON postings.transaction_id = transactions.id GROUP BY account
+					) p1
+					JOIN postings p2 ON p1.account = p2.account AND p1.max_dt = transactions.dt JOIN transactions ON p2.transaction_id = transactions.id GROUP BY p2.account
+				) p3
+				JOIN postings p4 ON p3.account = p4.account AND p3.max_tid = p4.transaction_id
+			''')
+			
+			for running_balance in running_balances.all():
+				result.accounts[running_balance.account] = Amount(running_balance.running_balance, reporting_commodity())
+		
+		if end_date is not None:
+			result = cls()
+			
+			running_balances = db.session.execute('''
+				SELECT p3.account, running_balance FROM
+				(
+					SELECT p1.account, max(p2.transaction_id) AS max_tid FROM
+					(
+						SELECT account, max(dt) AS max_dt FROM postings JOIN transactions ON postings.transaction_id = transactions.id WHERE dt <= :end_date GROUP BY account
+					) p1
+					JOIN postings p2 ON p1.account = p2.account AND p1.max_dt = transactions.dt JOIN transactions ON p2.transaction_id = transactions.id GROUP BY p2.account
+				) p3
+				JOIN postings p4 ON p3.account = p4.account AND p3.max_tid = p4.transaction_id
+			''', {'end_date': end_date})
+			
+			for running_balance in running_balances.all():
+				result.accounts[running_balance.account] = Amount(running_balance.running_balance, reporting_commodity())
+		
+		# Subtract balances at start_date from balances at end_date if required
+		if start_date is not None:
+			for k in result.accounts.keys():
+				# If k not in result_start_date, then the balance at start_date was necessarily 0 and subtraction is not required
+				if k in result_start_date.accounts:
+					result.accounts[k].quantity -= result_start_date.accounts[k].quantity
+		
+		return result
+	
 	def apply_transactions(self, transactions):
 		for transaction in transactions:
 			for posting in transaction.postings:
 				if posting.account not in self.accounts:
 					self.accounts[posting.account] = Amount(0, reporting_commodity())
 				
-				# FIXME: Handle commodities better
+				# FIXME: Handle commodities better (ensure compatible commodities)
 				self.accounts[posting.account].quantity += posting.amount().as_cost().quantity
 	
 	def transfer_balance(self, source_account, destination_account, description=None):

drcr/reports.py

@@ -17,7 +17,7 @@
 from flask import url_for
 
 from .models import AccountConfiguration, Amount, TrialBalancer, reporting_commodity
-from .webapp import all_transactions, eofy_date, sofy_date
+from .webapp import all_transactions, api_transactions, eofy_date, sofy_date
 
 from datetime import datetime, timedelta
 
@@ -154,8 +154,8 @@ def entries_for_kind(account_configurations, accounts, kind, neg=False, floor=0)
 
 def balance_sheet_report():
 	# Get trial balance
-	balancer = TrialBalancer()
+	balancer = TrialBalancer.from_cached()
-	balancer.apply_transactions(all_transactions())
+	balancer.apply_transactions(api_transactions())
 	
 	accounts = dict(sorted(balancer.accounts.items()))
 	
@@ -207,8 +207,8 @@ def income_statement_report(start_date=None, end_date=None):
 		end_date = eofy_date()
 	
 	# Get trial balance
-	balancer = TrialBalancer()
+	balancer = TrialBalancer.from_cached(start_date=start_date, end_date=end_date)
-	balancer.apply_transactions(all_transactions(start_date=start_date, end_date=end_date))
+	balancer.apply_transactions(api_transactions(start_date=start_date, end_date=end_date))
 	
 	accounts = dict(sorted(balancer.accounts.items()))
 	

drcr/views.py

@@ -20,7 +20,7 @@ from .database import db
 from .models import AccountConfiguration, Amount, Balance, Posting, TrialBalancer, reporting_commodity
 from .plugins import account_kinds, advanced_reports, data_sources
 from .reports import balance_sheet_report, income_statement_report
-from .webapp import all_transactions, app
+from .webapp import all_transactions, api_transactions, app
 
 from itertools import groupby
 
@@ -69,8 +69,8 @@ def general_ledger():
 
 @app.route('/trial-balance')
 def trial_balance():
-	balancer = TrialBalancer()
+	balancer = TrialBalancer.from_cached()
-	balancer.apply_transactions(all_transactions())
+	balancer.apply_transactions(api_transactions())
 	
 	total_dr = Amount(sum(v.quantity for v in balancer.accounts.values() if v.quantity > 0), reporting_commodity())
 	total_cr = Amount(sum(v.quantity for v in balancer.accounts.values() if v.quantity < 0), reporting_commodity())

drcr/webapp.py

@@ -22,7 +22,7 @@ app.config.from_file('config.toml', load=toml.load)
 from flask_sqlalchemy.record_queries import get_recorded_queries
 
 from .database import db
-from .models import Metadata, Transaction, reporting_commodity
+from .models import Amount, Metadata, Transaction, reporting_commodity
 from .plugins import init_plugins, transaction_providers
 from .statements.models import StatementLine
 
@@ -33,6 +33,8 @@ app.config['SQLALCHEMY_RECORD_QUERIES'] = app.debug
 db.init_app(app)
 
 def all_transactions(start_date=None, end_date=None, join_postings=True):
+	"""Return all transactions, including from DB and API"""
+	
 	# All Transactions in database between start_date and end_date
 	query = db.select(Transaction)
 	if start_date and end_date:
@@ -46,10 +48,21 @@ def all_transactions(start_date=None, end_date=None, join_postings=True):
 	
 	transactions = db.session.scalars(query).all()
 	
+	transactions.extend(api_transactions(start_date, end_date))
+	
+	return transactions
+
+def api_transactions(start_date=None, end_date=None):
+	"""Return only transactions from API"""
+	
+	transactions = []
+	
 	# Unreconciled StatementLines
+	# FIXME: Filter by start_date and end_date
 	transactions.extend(line.into_transaction() for line in StatementLine.query.filter(StatementLine.reconciliation == None))
 	
 	# Plugins
+	# FIXME: Filter by start_date and end_date
 	for transaction_provider in transaction_providers:
 		transactions.extend(transaction_provider())
 	
@@ -80,10 +93,33 @@ init_plugins()
 
 @app.cli.command('initdb')
 def initdb():
+	"""Initialise database tables"""
+	
 	db.create_all()
 	
 	# FIXME: Need to init metadata
 
+@app.cli.command('recache_balances')
+def recache_balances():
+	"""Recompute running_balance for all postings"""
+	
+	# Get all Transactions in database in correct order
+	transactions = db.session.scalars(db.select(Transaction).options(db.selectinload(Transaction.postings)).order_by(Transaction.dt, Transaction.id)).all()
+	
+	accounts = {}
+	
+	for transaction in transactions:
+		for posting in transaction.postings:
+			if posting.account not in accounts:
+				accounts[posting.account] = Amount(0, reporting_commodity())
+			
+			# FIXME: Handle commodities better (ensure compatible commodities)
+			accounts[posting.account].quantity += posting.amount().as_cost().quantity
+			
+			posting.running_balance = accounts[posting.account].quantity
+	
+	db.session.commit()
+
 @app.context_processor
 def add_reporting_commodity():
 	return dict(reporting_commodity=reporting_commodity())