Policy setting for client-side caching
An improved method and system for client-side caching that transparently caches suitable network files for offline use. A cache mechanism in a network redirector transparently intercepts requests to access server files, and if the requested file is locally cached, satisfies the request from the cache when possible. Otherwise the cache mechanism creates a local cache file and satisfies the request from the server, and also fills in a sparse cached file as reads for data in ranges that are missing in the cached file are requested and received from the server. A background process also fills in local files that are sparse, using the existing handle of already open server files, or opening, reading from and closing other server files. Security is also provided by maintaining security information received from the server for files that are in the cache, and using that security information to determine access to the file when offline.
1. A computer-readable medium having stored thereon computer-executable components for caching files and accessing network files, comprising:
a redirector component; and
a caching component configured to detect a file system-directed request for accessing a server file of a network server and to determine if a local file corresponding to the server file is already in a local cache; and
if the local file is in the local cache, to open the local file for access, and
if the local file is not in the local cache, to open the server file, and to analyze at least one policy setting associated with the server file that indicates whether a local file in the local cache may be created to correspond to the server file, and if so, creating the file.
2. The computer-readable medium of claim 1 wherein the caching component is part of the redirector component.
3. The computer-readable medium of claim 1 wherein the caching component further includes instructions for receiving security information corresponding to the server file from the network server, and for maintaining security data in association with the local file corresponding to the security information.
4. The computer-readable medium of claim 3 wherein the caching component further includes instructions for receiving a request to access a cached file, and for using the security information associated with the cached file to determine access to the file.