Add some more structuring

inflatinator/__main__.py

@@ -1,8 +1,11 @@
 import revbank
 import sys
+import logging
 
 
 def main(product_file):
+    logging.basicConfig(level=logging.DEBUG)
+
     with open(product_file, 'r') as fd:
         src = fd.read()
 

inflatinator/revbank.py

@@ -1,49 +1,75 @@
+from decimal import Decimal, ROUND_UP
+import logging
 import re
 import scrapers
-from decimal import Decimal, ROUND_UP
+
+profit_margin = Decimal('1.3')
 
 
-our_margin = Decimal('1.3')
+class AutoUpdate:
+    _meta_re = re.compile(r'#\s*(?P<vendor>ah):(?P<sku>\S+)\s+(?P<units>\d+)x$')
+
+    def __init__(self, vendor, sku, units):
+        self.vendor = vendor
+        self.sku = sku
+        self.units = units
+
+    def __str__(self):
+        return f'{self.vendor}:{self.sku} {self.units}x'
+
+    @staticmethod
+    def from_product_line(line):
+        m = AutoUpdate._meta_re.search(line)
+        if not m:
+            raise Exception('no auto update directive found')
+        return AutoUpdate(m['vendor'], m['sku'], int(m['units']))
+
+assert AutoUpdate.from_product_line('# ah:wi162664 8x')
+assert AutoUpdate.from_product_line('8711327538481,liuk 0.80  Ola Liuk  # ah:wi162664 8x')
 
 
-def find_product_details(vendor_and_sku):
-    [vendor, sku] = vendor_and_sku.split(':', 2)
-
-    if vendor == 'ah':
-        return scrapers.ah_get_by_sku(sku)
-
-    raise Exception(f'unknown vendor: {vendor}')
+def find_product_details(auto_update):
+    if auto_update.vendor == 'ah':
+        return scrapers.ah_get_by_sku(auto_update.sku, auto_update.units)
+    raise Exception(f'unknown vendor: {auto_update.vendor}')
 
 
 def update_product_pricings(src):
-    find_updatable = re.compile(r'#\s*(?P<sku>\S+)\s+(?P<units>\d+)x$')
     find_aliases = re.compile(r'^(?P<aliases>\S+)')
 
     lines = src.split('\n')
     lines_out = []
 
     for line in lines:
-        m = find_updatable.search(line)
-        if not m:
+        try:
+            auto_update = AutoUpdate.from_product_line(line)
+            logging.debug('Found updatable product: %s', auto_update)
+        except Exception as err:
             lines_out.append(line)
             continue
 
-        d = find_product_details(m['sku'])
+        try:
+            prod_info = find_product_details(auto_update)
+        except Exception as err:
+            logging.error('could not update %s %s: %s', auto_update, err)
+            lines_out.append(line)
+            continue
 
         product_aliases = set()
         if not line.startswith('#'):
             product_aliases = set(find_aliases.search(line)['aliases'].split(','))
-        product_aliases.add(d['ean'])
+        product_aliases.add(prod_info.ean)
 
         aliases = ','.join(sorted(product_aliases))
-        units = int(m["units"])
-        price = d['price']
 
-        # Apply a 30% margin and divide by the number of units per sold packaging.
-        unit_price = price * our_margin / units
+        # Apply profit margin and divide by the number of units per sold packaging.
+        unit_price = prod_info.price * profit_margin / prod_info.units
         # Round up to 5ct.
         unit_price = (unit_price * 20).quantize(Decimal('1'), rounding=ROUND_UP) / 20
 
-        lines_out.append(f'{aliases:<15} {unit_price:.2f}  {d["name"]:<32} # {m["sku"]} {units}x')
+        fmt_price = f'{unit_price:.2f}'
+        lines_out.append(f'{aliases:<15} {fmt_price:<6} {prod_info.name:<32} # {auto_update}')
+
+        logging.debug(f'Found "{prod_info.name}", buy €{prod_info.price/prod_info.units:.2f}, sell €{fmt_price}')
 
     return '\n'.join(lines_out)

inflatinator/scrapers.py

@@ -5,12 +5,23 @@ import re
 import subprocess
 
 
+class Product:
+    def __init__(self, name, price, ean, units):
+        self.name = name
+        self.price = price
+        self.ean = ean
+        self.units = units
+
+    def __str__(self):
+        return self.name
+
+
 def get(url):
     compl = subprocess.run(['links', '-source', url], capture_output=True)
     return compl.stdout
 
 
-def ah_get_by_sku(ah_sku):
+def ah_get_by_sku(ah_sku, units):
     assert re.match('^wi\d+$', ah_sku)
 
     html_src = get(f'https://www.ah.nl/producten/product/{ah_sku}')
@@ -24,14 +35,9 @@ def ah_get_by_sku(ah_sku):
     else:
         raise Exception(f'ah.nl returned no JSON metadata for SKU {ah_sku}')
 
-    name = schema['name']
-    ean = schema['gtin13']
-    sku = schema['sku']
-    price = Decimal(schema['offers']['price'])
-
-    return {
-        'name': name,
-        'price': price,
-        'ean': ean,
-        'sku': sku,
-    }
+    return Product(
+        name=schema['name'],
+        price=Decimal(schema['offers']['price']),
+        ean=schema['gtin13'],
+        units=units,
+    )