Move paginator plugin into structure module.

hyde/ext/plugins/structure.py

@@ -1,12 +1,16 @@
 # -*- coding: utf-8 -*-
 """
-Plugins related to folders and paths
+Plugins related to structure
 """
 
 from hyde.plugin import Plugin
 
-from fswrap import Folder
+from fswrap import File, Folder
 
+from hyde.site import Resource
+from hyde.util import pairwalk
+
+import os
 from fnmatch import fnmatch
 import operator
 
@@ -171,3 +175,141 @@ class CombinePlugin(Plugin):
         else:
             return "".join([text] + [r.source.read_all() for r in resources])
 
+
+class Page:
+    def __init__(self, posts, number):
+        self.posts = posts
+        self.number = number
+
+class Paginator:
+    """
+    Iterates resources which have pages associated with them.
+    """
+
+    file_pattern = 'page$PAGE/$FILE$EXT'
+
+    def __init__(self, settings):
+        self.sorter = getattr(settings, 'sorter', None)
+        self.size = getattr(settings, 'size', 10)
+        self.file_pattern = getattr(settings, 'file_pattern', self.file_pattern)
+
+    def _relative_url(self, source_path, number, basename, ext):
+        """
+        Create a new URL for a new page.  The first page keeps the same name;
+        the subsequent pages are named according to file_pattern.
+        """
+        path = File(source_path)
+        if number != 1:
+            filename = self.file_pattern.replace('$PAGE', str(number)) \
+                                    .replace('$FILE', basename) \
+                                    .replace('$EXT', ext)
+            path = path.parent.child(os.path.normpath(filename))
+        return path
+
+    def _new_resource(self, base_resource, node, page_number):
+        """
+        Create a new resource as a copy of a base_resource, with a page of
+        resources associated with it.
+        """
+        res = Resource(base_resource.source_file, node)
+        path = self._relative_url(base_resource.relative_path,
+                                page_number,
+                                base_resource.source_file.name_without_extension,
+                                base_resource.source_file.extension)
+        res.set_relative_deploy_path(path)
+        return res
+
+    @staticmethod
+    def _attach_page_to_resource(page, resource):
+        """
+        Hook up a page and a resource.
+        """
+        resource.page = page
+        page.resource = resource
+
+    @staticmethod
+    def _add_dependencies_to_resource(dependencies, resource):
+        """
+        Add a bunch of resources as dependencies to another resource.
+        """
+        if not hasattr(resource, 'depends'):
+            resource.depends = []
+        resource.depends.extend([dep.relative_path for dep in dependencies
+                                if dep.relative_path not in resource.depends])
+
+    def _walk_pages_in_node(self, node):
+        """
+        Segregate each resource into a page.
+        """
+        walker = 'walk_resources'
+        if self.sorter:
+            walker = 'walk_resources_sorted_by_%s' % self.sorter
+        walker = getattr(node, walker, getattr(node, 'walk_resources'))
+
+        posts = list(walker())
+        number = 1
+        while posts:
+            yield Page(posts[:self.size], number)
+            posts = posts[self.size:]
+            number += 1
+
+    def walk_paged_resources(self, node, resource):
+        """
+        Group the resources and return the new page resources.
+        """
+        added_resources = []
+        pages = list(self._walk_pages_in_node(node))
+        deps = reduce(list.__add__, [page.posts for page in pages], [])
+
+        Paginator._attach_page_to_resource(pages[0], resource)
+        Paginator._add_dependencies_to_resource(deps, resource)
+        for page in pages[1:]:
+            # make new resource
+            new_resource = self._new_resource(resource, node, page.number)
+            Paginator._attach_page_to_resource(page, new_resource)
+            new_resource.depends = resource.depends
+            added_resources.append(new_resource)
+
+        for prev, next in pairwalk(pages):
+            next.previous = prev
+            prev.next = next
+
+        return added_resources
+
+
+class PaginatorPlugin(Plugin):
+    """
+    Paginator plugin.
+
+    Configuration: in a resource's metadata:
+
+        paginator:
+            sorter: time
+            size: 5
+            file_pattern: page$PAGE/$FILE$EXT   # optional
+
+    then in the resource's content:
+
+        {% for res in resource.page.posts %}
+        {% refer to res.url as post %}
+        {{ post }}
+        {% endfor %}
+
+        {{ resource.page.previous }}
+        {{ resource.page.next }}
+
+    """
+    def __init__(self, site):
+        super(PaginatorPlugin, self).__init__(site)
+
+    def begin_site(self):
+        for node in self.site.content.walk():
+            added_resources = []
+            paged_resources = (res for res in node.resources
+                                 if hasattr(res.meta, 'paginator'))
+            for resource in paged_resources:
+                paginator = Paginator(resource.meta.paginator)
+                added_resources += paginator.walk_paged_resources(node, resource)
+
+            node.resources += added_resources
+

hyde/tests/sites/test_paginator/site.yaml

@@ -5,7 +5,7 @@ base_url: / # The base url for autogenerated links.
 plugins:
     - hyde.ext.plugins.meta.MetaPlugin
     - hyde.ext.plugins.sorter.SorterPlugin
-    - hyde.ext.plugins.paginator.PaginatorPlugin
+    - hyde.ext.plugins.structure.PaginatorPlugin
 meta:
     nodemeta: meta.yaml
     created: !!timestamp 2010-01-01 00:00:00