feat: add support for pagination

lektor_groupby/resolver.py

@@ -1,6 +1,6 @@
 from lektor.db import Record  # isinstance
-from lektor.utils import build_url
-from typing import TYPE_CHECKING, Dict, List, Tuple, Optional, Iterable
+from typing import TYPE_CHECKING, Dict, List, NamedTuple, Optional, Iterable
+from .util import build_url
 from .vobj import VPATH, GroupBySource
 if TYPE_CHECKING:
     from lektor.environment import Environment
@@ -8,6 +8,21 @@ if TYPE_CHECKING:
     from .config import Config
 
 
+class ResolverEntry(NamedTuple):
+    slug: str
+    group: str
+    config: 'Config'
+    page: Optional[int]
+
+    def equals(
+        self, path: str, attribute: str, group: str, page: Optional[int]
+    ) -> bool:
+        return self.slug == group \
+            and self.config.key == attribute \
+            and self.config.root == path \
+            and self.page == page
+
+
 class Resolver:
     '''
     Resolve virtual paths and urls ending in /.
@@ -15,7 +30,7 @@ class Resolver:
     '''
 
     def __init__(self, env: 'Environment') -> None:
-        self._data = {}  # type: Dict[str, Tuple[str, str, Config]]
+        self._data = {}  # type: Dict[str, ResolverEntry]
         env.urlresolver(self.resolve_server_path)
         env.virtualpathresolver(VPATH.lstrip('@'))(self.resolve_virtual_path)
 
@@ -34,7 +49,9 @@ class Resolver:
     def add(self, vobj: GroupBySource) -> None:
         ''' Track new virtual object (only if slug is set). '''
         if vobj.slug:
-            self._data[vobj.url_path] = (vobj.key, vobj.group, vobj.config)
+            # page_num = 1 overwrites page_num = None -> same url_path()
+            self._data[vobj.url_path] = ResolverEntry(
+                vobj.key, vobj.group, vobj.config, vobj.page_num)
 
     # ------------
     #   Resolver
@@ -46,7 +63,8 @@ class Resolver:
         if isinstance(node, Record):
             rv = self._data.get(build_url([node.url_path] + pieces))
             if rv:
-                return GroupBySource(node, rv[0]).finalize(rv[2], rv[1])
+                return GroupBySource(
+                    node, rv.slug, rv.page).finalize(rv.config, rv.group)
         return None
 
     def resolve_virtual_path(self, node: 'SourceObject', pieces: List[str]) \
@@ -54,8 +72,15 @@ class Resolver:
         ''' Admin UI only: Prevent server error and null-redirect. '''
         if isinstance(node, Record) and len(pieces) >= 2:
             path = node['_path']  # type: str
-            attr, grp, *_ = pieces
-            for slug, group, conf in self._data.values():
-                if attr == conf.key and slug == grp and path == conf.root:
-                    return GroupBySource(node, slug).finalize(conf, group)
+            attr, grp, *optional_page = pieces
+            page = None
+            if optional_page:
+                try:
+                    page = int(optional_page[0])
+                except ValueError:
+                    pass
+            for rv in self._data.values():
+                if rv.equals(path, attr, grp, page):
+                    return GroupBySource(
+                        node, rv.slug, rv.page).finalize(rv.config, rv.group)
         return None