overload & and | operators to chain filters (refs #1426)

weboob/tools/browser2/filters.py

@@ -66,6 +66,14 @@ class _Filter(object):
         self._creation_counter = _Filter._creation_counter
         _Filter._creation_counter += 1
 
+    def __or__(self, o):
+        self.default = o
+        return self
+
+    def __and__(self, o):
+        o.selector = self
+        return o
+
     def default_or_raise(self, exception):
         if self.default is not _NO_DEFAULT:
             return self.default
@@ -110,6 +118,41 @@ class Filter(_Filter):
         raise NotImplementedError()
 
 
+class _Selector(Filter):
+    def filter(self, txt):
+        if txt is not None:
+            return txt
+        else:
+            return self.default_or_raise(ParseError('Element %r not found' % self.selector))
+
+
+class Dict(_Selector):
+    @classmethod
+    def select(cls, selector, item):
+        if isinstance(item, dict):
+            content = item
+        else:
+            content = item.el
+
+        for el in selector.split('/'):
+            if el not in content:
+                return None
+
+            content = content.get(el)
+
+        return content
+
+
+class CSS(_Selector):
+    @classmethod
+    def select(cls, selector, item):
+        return item.cssselect(selector)
+
+
+class XPath(_Selector):
+    pass
+
+
 class Base(Filter):
     """
     Change the base element used in filters.
@@ -119,7 +162,7 @@ class Base(Filter):
         base = self.select(self.base, item)
         return self.selector(base)
 
-    def __init__(self, base, selector, default=_NO_DEFAULT):
+    def __init__(self, base, selector=None, default=_NO_DEFAULT):
         super(Base, self).__init__(selector, default)
         self.base = base
 
@@ -173,34 +216,6 @@ class TableCell(_Filter):
         return self.default_or_raise(ColumnNotFound('Unable to find column %s' % ' or '.join(self.names)))
 
 
-class Dict(Filter):
-    @classmethod
-    def select(cls, selector, item):
-        if isinstance(selector, basestring):
-            if isinstance(item, dict):
-                content = item
-            else:
-                content = item.el
-
-            for el in selector.split('/'):
-                if el not in content:
-                    return None
-
-                content = content.get(el)
-
-            return content
-        elif callable(selector):
-            return selector(item)
-        else:
-            return selector
-
-    def filter(self, txt):
-        if txt is not None:
-            return txt
-        else:
-            return self.default_or_raise(ParseError())
-
-
 class CleanHTML(Filter):
     def filter(self, txt):
         if isinstance(txt, (tuple, list)):
@@ -234,7 +249,7 @@ class CleanText(Filter):
     Second, it replaces all symbols given in second argument.
     """
 
-    def __init__(self, selector, symbols='', replace=[], childs=True, **kwargs):
+    def __init__(self, selector=None, symbols='', replace=[], childs=True, **kwargs):
         super(CleanText, self).__init__(selector, **kwargs)
         self.symbols = symbols
         self.toreplace = replace
@@ -283,7 +298,7 @@ class CleanDecimal(CleanText):
     Get a cleaned Decimal value from an element.
     """
 
-    def __init__(self, selector, replace_dots=True, default=_NO_DEFAULT):
+    def __init__(self, selector=None, replace_dots=True, default=_NO_DEFAULT):
         super(CleanDecimal, self).__init__(selector, default=default)
         self.replace_dots = replace_dots
 
@@ -318,7 +333,7 @@ class Link(Attr):
     If the <a> tag is not found, an exception IndexError is raised.
     """
 
-    def __init__(self, selector, default=_NO_DEFAULT):
+    def __init__(self, selector=None, default=_NO_DEFAULT):
         super(Link, self).__init__(selector, 'href', default=default)
 
 
@@ -345,8 +360,9 @@ class Regexp(Filter):
     u'1988-08-13'
     """
 
-    def __init__(self, selector, pattern, template=None, flags=0, default=_NO_DEFAULT):
+    def __init__(self, selector=None, pattern=None, template=None, flags=0, default=_NO_DEFAULT):
         super(Regexp, self).__init__(selector, default=default)
+        assert pattern is not None
         self.pattern = pattern
         self.regex = re.compile(pattern, flags)
         self.template = template
@@ -379,7 +395,7 @@ class Map(Filter):
 
 
 class DateTime(Filter):
-    def __init__(self, selector, default=_NO_DEFAULT, dayfirst=False, translations=None):
+    def __init__(self, selector=None, default=_NO_DEFAULT, dayfirst=False, translations=None):
         super(DateTime, self).__init__(selector, default=default)
         self.dayfirst = dayfirst
         self.translations = translations
@@ -397,7 +413,7 @@ class DateTime(Filter):
 
 
 class Date(DateTime):
-    def __init__(self, selector, default=_NO_DEFAULT, dayfirst=False, translations=None):
+    def __init__(self, selector=None, default=_NO_DEFAULT, dayfirst=False, translations=None):
         super(Date, self).__init__(selector, default=default, dayfirst=dayfirst, translations=translations)
 
     def filter(self, txt):
@@ -435,7 +451,7 @@ class Time(Filter):
     regexp = re.compile(r'(?P<hh>\d+):?(?P<mm>\d+)(:(?P<ss>\d+))?')
     kwargs = {'hour': 'hh', 'minute': 'mm', 'second': 'ss'}
 
-    def __init__(self, selector, default=_NO_DEFAULT):
+    def __init__(self, selector=None, default=_NO_DEFAULT):
         super(Time, self).__init__(selector, default=default)
 
     def filter(self, txt):
@@ -486,7 +502,7 @@ class Format(MultiFilter):
 
 
 class Join(Filter):
-    def __init__(self, pattern, selector, textCleaner=CleanText):
+    def __init__(self, pattern, selector=None, textCleaner=CleanText):
         super(Join, self).__init__(selector)
         self.pattern = pattern
         self.textCleaner = textCleaner

weboob/tools/browser2/page.py

@@ -642,6 +642,9 @@ class AbstractElement(object):
     def parse(self, obj):
         pass
 
+    def cssselect(self, *args, **kwargs):
+        return self.el.cssselect(*args, **kwargs)
+
     def xpath(self, *args, **kwargs):
         return self.el.xpath(*args, **kwargs)