Added printing requirements

zope/schema/_schema.py

@@ -0,0 +1,90 @@
+##############################################################################
+#
+# Copyright (c) 2002 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.
+#
+##############################################################################
+"""Schema convenience functions
+"""
+
+import zope.interface.verify
+
+
+def getFieldNames(schema):
+    """Return a list of all the Field names in a schema.
+    """
+    from zope.schema.interfaces import IField
+    return [name for name in schema if IField.providedBy(schema[name])]
+
+
+def getFields(schema):
+    """Return a dictionary containing all the Fields in a schema.
+    """
+    from zope.schema.interfaces import IField
+    fields = {}
+    for name in schema:
+        attr = schema[name]
+        if IField.providedBy(attr):
+            fields[name] = attr
+    return fields
+
+
+def getFieldsInOrder(schema, _field_key=lambda x: x[1].order):
+    """Return a list of (name, value) tuples in native schema order.
+    """
+    return sorted(getFields(schema).items(), key=_field_key)
+
+
+def getFieldNamesInOrder(schema):
+    """Return a list of all the Field names in a schema in schema order.
+    """
+    return [name for name, field in getFieldsInOrder(schema)]
+
+
+def getValidationErrors(schema, object):
+    """Return a list of all validation errors.
+    """
+    errors = getSchemaValidationErrors(schema, object)
+    if errors:
+        return errors
+
+    # Only validate invariants if there were no previous errors. Previous
+    # errors could be missing attributes which would most likely make an
+    # invariant raise an AttributeError.
+    invariant_errors = []
+    try:
+        schema.validateInvariants(object, invariant_errors)
+    except zope.interface.exceptions.Invalid:
+        # Just collect errors
+        pass
+    errors = [(None, e) for e in invariant_errors]
+    return errors
+
+
+def getSchemaValidationErrors(schema, object):
+    errors = []
+    for name in schema.names(all=True):
+        if zope.interface.interfaces.IMethod.providedBy(schema[name]):
+            continue
+        attribute = schema[name]
+        if not zope.schema.interfaces.IField.providedBy(attribute):
+            continue
+        try:
+            value = getattr(object, name)
+        except AttributeError as error:
+            # property for the given name is not implemented
+            errors.append((
+                name, zope.schema.interfaces.SchemaNotFullyImplemented(error)))
+        else:
+            try:
+                attribute.bind(object).validate(value)
+            except zope.schema.ValidationError as e:
+                errors.append((name, e))
+    return errors