find

oml/meta/utils.py

@@ -1,5 +1,16 @@
-
+import re
+import stdnum.isbn
 
 def normalize_isbn(value):
     return ''.join([s for s in value if s.isdigit() or s == 'X'])
 
+def find_isbns(text):
+    matches = re.compile('\d[\d\-X\ ]+').findall(text)
+    matches = [normalize_isbn(value) for value in matches]
+    return [isbn for isbn in matches if stdnum.isbn.is_valid(isbn)
+        and len(isbn) in (10, 13)
+        and isbn not in (
+        '0' * 10,
+        '0' * 13,
+    )]
+