Added printing requirements

z3c/rml/directive.py

@@ -0,0 +1,123 @@
+##############################################################################
+#
+# Copyright (c) 2007 Zope Foundation and Contributors.
+# All Rights Reserved.
+#
+# This software is subject to the provisions of the Zope Public License,
+# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
+# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
+# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
+# FOR A PARTICULAR PURPOSE.
+#
+##############################################################################
+"""RML Directive Implementation
+"""
+import logging
+import zope.interface
+import zope.schema
+
+from lxml import etree
+from z3c.rml import interfaces
+from z3c.rml.attr import getManager
+
+logging.raiseExceptions = False
+logger = logging.getLogger("z3c.rml")
+
+ABORT_ON_INVALID_DIRECTIVE = False
+
+def DeprecatedDirective(iface, reason):
+    zope.interface.directlyProvides(iface, interfaces.IDeprecatedDirective)
+    iface.setTaggedValue('deprecatedReason', reason)
+    return iface
+
+def getFileInfo(directive, element=None):
+    root = directive
+    while root.parent:
+        root = root.parent
+    if element is None:
+        element = directive.element
+    return '(file %s, line %i)' %(root.filename, element.sourceline)
+
+class RMLDirective(object):
+    zope.interface.implements(interfaces.IRMLDirective)
+    signature = None
+    factories = {}
+
+    def __init__(self, element, parent):
+        self.element = element
+        self.parent = parent
+
+    def getAttributeValues(self, ignore=None, select=None, attrMapping=None,
+                           includeMissing=False, valuesOnly=False):
+        """See interfaces.IRMLDirective"""
+        manager = getManager(self)
+        cache = '%s.%s' % (self.signature.__module__, self.signature.__name__)
+        if cache in manager.attributesCache:
+            fields = manager.attributesCache[cache]
+        else:
+            fields = []
+            for name, attr in zope.schema.getFieldsInOrder(self.signature):
+                fields.append((name, attr))
+            manager.attributesCache[cache] = fields
+
+        items = []
+        for name, attr in fields:
+            # Only add the attribute to the list, if it is supposed there
+            if ((ignore is None or name not in ignore) and
+                (select is None or name in select)):
+                # Get the value.
+                value = attr.bind(self).get()
+                # If no value was found for a required field, raise a value
+                # error
+                if attr.required and value is attr.missing_value:
+                    raise ValueError(
+                        'No value for required attribute "%s" '
+                        'in directive "%s" %s.' % (
+                        name, self.element.tag, getFileInfo(self)))
+                # Only add the entry if the value is not the missing value or
+                # missing values are requested to be included.
+                if value is not attr.missing_value or includeMissing:
+                    items.append((name, value))
+
+        # Sort the items based on the section
+        if select is not None:
+            select = list(select)
+            items = sorted(items, key=lambda (n, v): select.index(n))
+
+        # If the attribute name does not match the internal API
+        # name, then convert the name to the internal one
+        if attrMapping:
+            items = [(attrMapping.get(name, name), value)
+                     for name, value in items]
+
+        # Sometimes we only want the values without the names
+        if valuesOnly:
+            return [value for name, value in items]
+
+        return items
+
+    def processSubDirectives(self, select=None, ignore=None):
+        # Go through all children of the directive and try to process them.
+        for element in self.element.getchildren():
+            # Ignore all comments
+            if isinstance(element, etree._Comment):
+                continue
+            # Raise an error/log any unknown directive.
+            if element.tag not in self.factories:
+                msg = "Directive %r could not be processed and was " \
+                      "ignored. %s" %(element.tag, getFileInfo(self, element))
+                # Record any tags/elements that could not be processed.
+                logger.warn(msg)
+                if ABORT_ON_INVALID_DIRECTIVE:
+                    raise ValueError(msg)
+                continue
+            if select is not None and element.tag not in select:
+                continue
+            if ignore is not None and element.tag in ignore:
+                continue
+            directive = self.factories[element.tag](element, self)
+            directive.process()
+
+    def process(self):
+        self.processSubDirectives()