Defined adapters for export/import of nodes

git-svn-id: svn://svn.cy55.de/Zope3/src/loops/trunk@1008 fd906abe-77d9-0310-91a1-e0d9ade77398

README.txt

@@ -264,8 +264,56 @@ to the bottom, and to the top
   >>> m11.keys()
   ['m111', 'm114', 'm112', 'm113']
 
+Import/Export
+-------------
+
+Nodes may be exported to and loaded from external sources, typically
+file representations that allow the transfer of nodes from one Zope
+instance to another.
+
+  >>> from loops.external import NodesLoader
+  >>> loader = NodesLoader(views)
+  >>> data = [{'name': 'm2', 'path': '', 'description': u'desc 1',
+  ...          'title': u'M 2', 'body': u'test m2', 'nodeType': 'menu' },
+  ...         {'name': 'm21', 'path': 'm2', 'description': u'',
+  ...          'title': u'M 21', 'body': u'test m21', 'nodeType': 'page' },
+  ...         {'name': 'm114', 'path': 'm1/m11', 'description': u'',
+  ...          'title': u'M 114', 'body': u'test m114', 'nodeType': 'page' },]
+  >>> loader.load(data)
+  >>> views['m2']['m21'].title
+  u'M 21'
+  >>> views['m1']['m11']['m114'].title
+  u'M 114'
+
+  >>> from loops.external import NodesExporter, NodesImporter
+  >>> exporter = NodesExporter(views)
+  >>> data = exporter.extractData()
+  >>> len(data)
+  8
+  >>> data[3]['path']
+  u'm1/m11'
+  >>> data[3]['name']
+  u'm112'
+
+  >>> import os
+  >>> dumpname = os.path.dirname(__file__) + '/test.tmp'
+  >>> exporter.filename = dumpname
+  >>> exporter.dumpData()
+
+Load them again from the exported file:
+  
+  >>> importer = NodesImporter(views)
+  >>> importer.filename = dumpname
+  >>> imported = importer.getData()
+  >>> imported == data
+  True
+
+  >>> loader.load(imported)
+
+
 Fin de partie
 =============
 
+  >>> os.unlink(dumpname)
   >>> placefulTearDown()
 

configure.zcml

@@ -173,6 +173,14 @@
 
   </content>
 
+  <!-- adapters for export/import -->
+
+  <adapter factory="loops.external.NodesLoader" />
+
+  <adapter factory="loops.external.NodesExporter" />
+
+  <adapter factory="loops.external.NodesImporter" />
+
   <!-- Register various browser related components, including all views -->
   <include package=".browser" />
 

external.py

@@ -0,0 +1,157 @@
+#
+#  Copyright (c) 2005 Helmut Merz helmutm@cy55.de
+#
+#  This program is free software; you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation; either version 2 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful,
+#  but WITHOUT ANY WARRANTY; without even the implied warranty of
+#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#  GNU General Public License for more details.
+#
+#  You should have received a copy of the GNU General Public License
+#  along with this program; if not, write to the Free Software
+#  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+#
+
+"""
+Adapter implementations for export, import, ...
+
+$Id$
+"""
+
+from zope.interface import implements, Interface
+from zope.app import zapi
+from zope.component import adapts
+
+from loops.interfaces import IViewManager
+from loops.view import Node
+
+
+# import/export interfaces (for adapters)
+    
+class IExternalContentSource(Interface):
+    """ Provides content from an external source.
+    """
+
+    def getData():
+        """ Retrieve content from the external source; return a sequence of
+            dictionaries in a format like this:
+            [{'name': ..., 'title': ..., 'body':... }, ...],
+        """
+
+
+class ILoader(Interface):
+    """ Inserts data provided by an IExternalContentSource object into the
+        database.
+    """
+
+    def load(data):
+        """ Create objects as defined by the data given; this is a sequence
+            as described for IExternalContentSource.getContent().
+        """
+
+
+class IExporter(Interface):
+    """ Extracts data and in a format usable by ILoader.
+
+        Optionally dump data to a file.
+    """
+
+    def extractData():
+        """ Return a data object as described for
+            IExternalContentSource.getData().
+        """
+
+    def dumpData(file):
+        """ Dump data returned by extractData() to the file given in a
+            format that might be read in by a suitable implementation of
+            IExternalContentSource.
+        """
+
+
+# implementations for views/nodes
+
+class NodesLoader(object):
+
+    implements(ILoader)
+    adapts(IViewManager)
+
+    def __init__(self, context):
+        self.context = context
+
+    def load(self, data):
+        for item in data:
+            name = item['name']
+            path = item['path']
+            parent = zapi.traverse(self.context, path)
+            if name in parent: # replace existing objects
+                del parent[name]
+            node = Node()
+            node.title = item['title']
+            node.description = item['description']
+            node.body = item['body']
+            node.nodeType = item['nodeType']
+            parent[name] = node
+
+
+class NodesExporter(object):
+
+    implements(IExporter)
+    adapts(IViewManager)
+
+    filename = 'loops.dmp'
+
+    def __init__(self, context):
+        self.context = context
+
+    def extractData(self):
+        data = []
+        for child in self.context.values():
+            self.extractNodeData(child, '', data)
+        return data
+    
+    def extractNodeData(self, item, path, data):
+        name = zapi.getName(item)
+        data.append({
+                'name': name,
+                'path': path,
+                'description': item.description,
+                'title': item.title,
+                'body': item.body,
+                'nodeType': item.nodeType
+        })
+        path = path and '%s/%s' % (path, name) or name
+        for child in item.values():
+            self.extractNodeData(child, path, data)
+        
+
+    def dumpData(self, file=None, noclose=False):
+        if file is None:
+            file = open(self.filename, 'w')
+        data = self.extractData()
+        text = `data`.replace('},', '},\n').replace('}],', '}],\n')
+        file.write(text)
+        if not noclose:
+            file.close()
+
+
+class NodesImporter(object):
+
+    implements(IExternalContentSource)
+    adapts(IViewManager)
+
+    filename = 'loops.dmp'
+
+    def __init__(self, context):
+        self.context = context
+    
+    def getData(self, file=None):
+        if file is None:
+            file = open(self.filename, 'r')
+        data = file.read().replace('\n', '')
+        file.close()
+        return eval(data, {}, {})
+