InvenTree/InvenTree/part/migrations/0056_auto_20201110_1125.py
2022-02-25 17:17:34 +11:00

156 lines
4.8 KiB
Python

# Generated by Django 3.0.7 on 2020-11-10 11:25
import logging
from django.db import migrations
from moneyed import CURRENCIES
from django.db import migrations, connection
from company.models import SupplierPriceBreak
logger = logging.getLogger('inventree')
def migrate_currencies(apps, schema_editor):
"""
Migrate from the 'old' method of handling currencies,
to the new method which uses the django-money library.
Previously, we created a custom Currency model,
which was very simplistic.
Here we will attempt to map each existing "currency" reference
for the SupplierPriceBreak model, to a new django-money compatible currency.
"""
logger.info("Updating currency references for SupplierPriceBreak model...")
# A list of available currency codes
currency_codes = CURRENCIES.keys()
cursor = connection.cursor()
# The 'suffix' field denotes the currency code
response = cursor.execute('SELECT id, suffix, description from common_currency;')
results = cursor.fetchall()
remap = {}
for index, row in enumerate(results): # pragma: no cover
pk, suffix, description = row
suffix = suffix.strip().upper()
if suffix not in currency_codes:
print("Missing suffix:", suffix)
while suffix not in currency_codes:
# Ask the user to input a valid currency
print(f"Could not find a valid currency matching '{suffix}'.")
print("Please enter a valid currency code")
suffix = str(input("> ")).strip()
if pk not in remap.keys():
remap[pk] = suffix
# Now iterate through each PartSellPriceBreak and update the rows
response = cursor.execute('SELECT id, cost, currency_id, price, price_currency from part_partsellpricebreak;')
results = cursor.fetchall()
count = 0
for index, row in enumerate(results): # pragma: no cover
pk, cost, currency_id, price, price_currency = row
# Copy the 'cost' field across to the 'price' field
response = cursor.execute(f'UPDATE part_partsellpricebreak set price={cost} where id={pk};')
# Extract the updated currency code
currency_code = remap.get(currency_id, 'USD')
# Update the currency code
response = cursor.execute(f"UPDATE part_partsellpricebreak set price_currency='{currency_code}' where id={pk};")
count += 1
if count > 0: # pragma: no cover
print(f"Updated {count} SupplierPriceBreak rows")
def reverse_currencies(apps, schema_editor): # pragma: no cover
"""
Reverse the "update" process.
Here we may be in the situation that the legacy "Currency" table is empty,
and so we have to re-populate it based on the new price_currency codes.
"""
print("Reversing currency migration...")
cursor = connection.cursor()
# Extract a list of currency codes which are in use
response = cursor.execute(f'SELECT id, price, price_currency from part_partsellpricebreak;')
results = cursor.fetchall()
codes_in_use = set()
for index, row in enumerate(results):
pk, price, code = row
codes_in_use.add(code)
# Copy the 'price' field back into the 'cost' field
response = cursor.execute(f'UPDATE part_partsellpricebreak set cost={price} where id={pk};')
# Keep a dict of which currency objects map to which code
code_map = {}
# For each currency code in use, check if we have a matching Currency object
for code in codes_in_use:
response = cursor.execute(f"SELECT id, suffix from common_currency where suffix='{code}';")
row = cursor.fetchone()
if row is not None:
# A match exists!
pk, suffix = row
code_map[suffix] = pk
else:
# No currency object exists!
description = CURRENCIES[code]
# Create a new object in the database
print(f"Creating new Currency object for {code}")
# Construct a query to create a new Currency object
query = f"INSERT into common_currency (symbol, suffix, description, value, base) VALUES ('$', '{code}', '{description}', 1.0, False);"
response = cursor.execute(query)
code_map[code] = cursor.lastrowid
# Ok, now we know how each suffix maps to a Currency object
for suffix in code_map.keys():
pk = code_map[suffix]
# Update the table to point to the Currency objects
print(f"Currency {suffix} -> pk {pk}")
response = cursor.execute(f"UPDATE part_partsellpricebreak set currency_id={pk} where price_currency='{suffix}';")
class Migration(migrations.Migration):
atomic = False
dependencies = [
('part', '0055_auto_20201110_1001'),
]
operations = [
migrations.RunPython(migrate_currencies, reverse_code=reverse_currencies),
]