| 摘要 |
Embodiments disclosed herein provide a “lazy” approach in caching a hierarchical navigation tree with one or more associated permission trees. In one embodiment, only a portion of a cached permission tree is updated. One embodiment of a method may comprise determining whether a dirty node exists by comparing tree timestamps of the permission tree and the master tree. If the tree timestamp of the master tree is temporally more recent than the tree timestamp of the permission tree, the permission tree has a dirty node and the method may operate to check node timestamps of the master and permission trees. This process may be repeated until the dirty node is found, at which time a portion of the permission tree associated with the dirty node may be reconstructed, rather than the entire permission tree itself, thereby eliminating or significantly reducing access time to the cached permission tree. |
| 主权项 |
1. A method of caching hierarchical items in a network environment, the method comprising:
receiving, by a server machine from a computing device communicatively connected to the server machine, a request for a change to a web site; updating, by the server machine, a master tree to reflect the change to the web site, the master tree having nodes representing hierarchical items of the web site and edges representing hierarchical relationships among the hierarchical items, each node of the nodes in the master tree having a tree timestamp and a node timestamp, the updating including updating the tree timestamp and the node timestamp of a first node affected by the change and updating the tree timestamp of any upstream parent node of the first node in the master tree; determining, by the server machine, a permission tree affected by the change, the permission tree associated with a user group permitted to view a particular portion of the hierarchical items of the web site, the permission tree having a set of nodes corresponding to the particular portion of the hierarchical items of the web site and representing access restriction of the user group to the particular portion of the hierarchical items of the web site; identifying, by the server machine, a dirty node in the permission tree, the identifying including comparing the tree timestamp of a root node of the master tree with a tree timestamp of a root node of the permission tree; and constructing, by the server machine, a portion of the permission tree containing the dirty node, the constructing including updating the tree timestamp and the node timestamp of the dirty node and updating the tree timestamp of any upstream parent node of the dirty node in the portion of the permission tree containing the dirty node such that only the portion of the permission tree affected by the change is updated. |
