CSE322 Offline 1: HTTP File server Solution

Task 1:
In this problem, you need to develop a web server that can handle multiple incoming HTTP GET requests and send HTTP response message back to the client, with appropriate Content-type in the response (according to the standard http protocol). The requirements of the web server are-
• Listen on a specified port, other than the standard port 80, and accept HTTP requests.
• Handle each HTTP request in a separate thread.
• Extract filename from HTTP request and return the file or an appropriate error message. If we type “localhost:port/path” in the address bar of a browser then:
1. If path is a directory, then generate an html page showing the list of files inside as links (for differentiability purpose, you must show the directory names with bold fonts). Each element in the list must be a link. If we click on a directory link, server enters into that directory and shows the list of files in the new directory. If we click on a file link, that file must be downloaded.
2. If path is a file, then enforce downloading it to the browser by specifying the contenttype in the response message. (Must send the file in fragments of specific chunk size)
3. If path is not found, then generate a 404: Page not found error message to the browser and also in the console of the server.
• Return a HTTP response message and close the client socket connection.
• Return appropriate status code, e.g. 200 (OK) or 404 (NOT FOUND), in the response.
• Determine and send the correct MIME type specifier in the response message.
• Your web server must be able to serve other HTTP requests while a file download is going on.
• You need to generate an appropriate log file for the corresponding http request. The log file will contain both the http request and also the http response messages.
Task 2:
Here, you will have to implement a “Client” program that will connect to the “Web Server” of Task 1. It will only be used to upload files to the “root” directory of the server. You have to implement it in such a way that a client can upload multiple files in parallel. So, the requirements of the client are:
• Connect to the specified port of the web server.
• Take file name as input from the console.
• Handle each file upload request in a thread.
• Upload the file to the root directory of the server in fragments of specific chunk size.
• If the given file name is invalid, write an error message to both the console of the server and the client.
Bonus Task:
Additionally, you can implement the HTTP PUT method besides GET method. The requirements of the bonus task are:
• Add a file browser to the root directory page of the web server.
• Submit the PUT request through a button.
• Upload the selected file to the root directory of the web server.
• Return a HTTP response message and close the client socket connection.
Implementation:
HTTP GET request message to the web server will be of the form:
“GET /… HTTP/1.1”
Make the file upload request message from the client to the server of the form:
“UPLOAD filename”
You can use the above information to figure out how to handle the requests from the web browser and the java client process as per the requirements.
Warnings:
• You need to implement the basics of http protocol accordingly; therefore, you cannot use any JAVA high level library. You cannot use Javascript. All the operations should be strictly limited to Socket Programming and html manipulation.
Task 1 Show Directory 5
File download 6
Error: Not found 2
Parallel requests 3
Log file 2
Task 2 File upload 5
Error message 2
Parallel upload 3
Bonus File upload 5
Task 0 Proper submission 2
Total 30+5