From 0bda603f1e573edbae5825d0e0380181fcef32c5 Mon Sep 17 00:00:00 2001
From: Helmut Merz <helmutm@cy55.de>
Date: Wed, 13 Mar 2024 09:11:28 +0100
Subject: [PATCH] first working version of URL traversal over folders via
 publication and view

---
 scopes/interfaces.py     | 16 +++++++++++++---
 scopes/server/app.py     | 37 +++++++++++++++++++++++++++++++++++--
 scopes/storage/folder.py |  6 +++++-
 3 files changed, 53 insertions(+), 6 deletions(-)

diff --git a/scopes/interfaces.py b/scopes/interfaces.py
index 8d1eef1..0fca68d 100644
--- a/scopes/interfaces.py
+++ b/scopes/interfaces.py
@@ -5,15 +5,18 @@ from zope.interface import Interface
 
 class ITraversable(Interface):
 
+    def get(key, default):
+        """Return the item addressed by `key`; return `default` if not found."""
+
+
+class IContainer(ITraversable):
+
     def items():
         """Return a sequence of key, value pairs of child objects."""
 
     def keys():
         """Return a sequence of keys of child objects."""
 
-    def get(key, default):
-        """Return the item addressed by `key`; return `default` if not found."""
-
     def __getitem__(key):
         """Return the item addressed by `key`; rais KeyError if not found."""
 
@@ -22,3 +25,10 @@ class ITraversable(Interface):
 
         May modify `value` so that the attributes referencing this object
         and the value object (e.g. `parent´ and `name`) are stored correctly."""
+
+
+class IView(Interface):
+
+    def __call__():
+        """Render the view data as HTML or JSON."""
+
diff --git a/scopes/server/app.py b/scopes/server/app.py
index 1ed9223..b377199 100644
--- a/scopes/server/app.py
+++ b/scopes/server/app.py
@@ -1,10 +1,14 @@
 # scopes.server.app
 
+import json
+from zope.interface import implementer
 from zope.publisher.base import DefaultPublication
 from zope.publisher.browser import BrowserRequest
+from zope.publisher.interfaces import NotFound
 from zope.publisher.publish import publish
 from zope.traversing.publicationtraverse import PublicationTraverser
 
+from scopes.interfaces import IContainer, ITraversable, IView
 from scopes.storage.folder import Root
 
 
@@ -15,7 +19,7 @@ def zope_app_factory(config):
         appRoot = Root(storage, config)
         request = BrowserRequest(environ['wsgi.input'], environ)
         request.setPublication(Publication(appRoot))
-        request = publish(request, True)
+        request = publish(request, False)
         response = request.response
         start_response(response.getStatusString(), response.getHeaders())
         return response.consumeBodyIter()
@@ -24,5 +28,34 @@ def zope_app_factory(config):
 
 class Publication(DefaultPublication):
 
-    pass
+    def traverseName(self, request, ob, name):
+        next = None
+        if ITraversable.providedBy(ob):
+            next = ob.get(name)
+        if next is None:
+            if name == 'index.html':
+                next = DefaultView(ob, request)
+        if next is None:
+            raise NotFound(ob, name, request)
+        return next
+
+    def getDefaultTraversal(self, request, ob):
+        if IView.providedBy(ob):
+            return ob, ()
+        return ob, ('index.html',)
+
+
+@implementer(IView)
+class DefaultView:
+
+    def __init__(self, context, request):
+        self.context = context
+        self.request = request
+
+    def __call__(self):
+        ob = self.context
+        result = dict(head=ob.head, data=ob.data)
+        if IContainer.providedBy(ob):
+            result['items'] = list(ob.keys())
+        return json.dumps(result)
 
diff --git a/scopes/storage/folder.py b/scopes/storage/folder.py
index 961294a..c459ae8 100644
--- a/scopes/storage/folder.py
+++ b/scopes/storage/folder.py
@@ -1,9 +1,13 @@
 # scopes.storage.folder
 
+from zope.interface import implementer
+
+from scopes.interfaces import IContainer
 from scopes.storage.common import registerContainerClass
 from scopes.storage.tracking import Container, Track
 
 
+@implementer(IContainer)
 class Folder(Track):
     """Needs docstring to be traversable."""
 
@@ -33,7 +37,7 @@ class Folder(Track):
         value.set('name', key)
         self.container.save(value)
 
-    def __call__(self, request=None):
+    def __str__(self):
         return 'folder: %s; keys: %s' % (self.name, list(self.keys()))