Simple Web Server
A simple web-server, to play with the Rust programming language
The goal is not performance, but rather discovering the language and building a simple distributed system. There exists a lot of work on how to improve the performance of servers (e.g., the C10k problem).
The C server serves as a reference implementation: the Rust server must have the same functionalities.
Rust implementation
The Rust implementation is located in the rust/ directory. It has been successfully compiled and used with version 0.6 of the language:
$ rustc --version
rustc 0.6
host: x86_64-unknown-linux-gnu
The source code is organized in the following files:
- parse_arguments.rs: a simple test on how to get and parse the command line arguments.
- read_file.rs: a simple test on how to read a file.
- echo_server.rs: a simple echo server in TCP.
- ws.rs: the simple web server
The server accepts several simultaneous connections: it spawns a new task for each accept. The pool_size argument has no effect. Moreover, the server does not make the difference between "file not found" and "not authorized": it returns a 404 error in both cases.
C implementation
The C implementation is located in the c/ directory. The source code is organized in the following files:
- main.c: entry point. The main part of this file is the function accept_connections(), which creates the server socket.
- pool.[c+h]: the pool of threads, which accept new connections and handle the requests. The threads use the file_manager in order to get the content of the requested files.
- file_manager.[c+h]: several functions to open and manage the server files.
- util.h: some constants and debugging stuff.
One can define USE_SENDFILE in util.h in order to use the sendfile() system call instead of read() the file and then write() its content to the socket.
How to compile and use the server
Both the C and Rust servers are compiled using the make command. The Makefile creates the ws executable in the source code folder.
To run the server:
$ ./ws -p port -s pool_size -d web_dir
You can retrieve files using telnet:
$ telnet server_ip server_port
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
GET /test.txt HTTP/1.0
HTTP/1.0 200 OK
...
Or using curl:
$ curl -0 http://server_ip:server_port/test.txt
You can also use your favorite web browser, but make sure to send HTTP/1.0 requests, otherwise you will get a "505 HTTP version not supported" error. For instance, in Firefox, enter about:config in the address box, search for the entry network.http.version, modify its value to 1.0, and restart Firefox.
The www directory contains several example files to test the web server.
Evaluation
We have evaluated the two implementation on a cluster of 17 machines. Details are presented here. The scripts used to run the experiments can be found in the scripts directory.