R as shared library
From: A.J. Rossini [mailto:rossini@blindglobe.net] Jeffrey Horner <jeff.horner@vanderbilt.edu> writes:
Good point. However, I chose this route to 1) understand R and its internals, which is more complicated than I thought, 2) write an apache module, which I've always wanted to do, and 3) leverage Apache's robust server technology. In my opinion, no other server software is as scalable and reliable as Apache. Plus, it has a module API to plugin other code, like an R interpreter.
All good reasons. But what is the final API going to look like? Are you planning on SSI's for the general interface?
For my prototype which already works, it's as simple as placing your code in a .R file accessible from the web server. That means your R code is responsible for generating HTML, similar to other languages embedded into Apache like Perl and Python. PHP is different in that the interpreter is only entered once a special tag is seen: file.php ------------- <html> <body> <?php /* php code here */ ?> </body> </html> ------------- And you can jump into and out of the interpreter an unlimited number of times. This allows for embedding parts of the HTML document within your code. Whether or not this is a good thing is debatable. The problem I'm working on right now, and which was talked about in the previous emails, is how to expose the CGI data to the R interpreter. Another part of this is how tight should R hook into Apache. Languages like Perl and Python expose many different parts of the http request to be overidden by language specific handlers, whereas PHP doesn't. My intent is to release a proof of concept prototype and then work with the R developer community to determine how it should evolve. Jeff