Ian C. Blenke wrote:
When NDFS is exposed to userspace for scripts to use, admins types will
embrace it for managing the cluster.
Our intent is to add some servlets which run on each datanode providing
access to the filesystem for non-Java programs.
Most operations would be quite simple, e.g.:
- to write a file, post its content to a url like:
http://datanode:XXXX/write?name=my.file
- to read a file, get file content from urls like:
http://datanode:XXXX/read?name=my.file
http://datanode:XXXX/read?name=my.file&start=2048&length=1024
- to remove a file:
http://datanode:XXX/remove?name=my.file
Similarly for rename, copy, etc.
The only somewhat complicated thing would be directory listings. These
would be handled with a simple REST interface, where some simple XML is
returned. Ideally a stylesheet could be specified so that one can use
the directory listing url to view the filesystem from a brower.
These servlets could easily be implemented in terms of the
NutchFileSystem API, and deployed with Jetty. To my knowledge, no one
is currently working on this. A volunteer would be welcome.
Doug
