Stanley Cheah Tiffany Yuen
In order to compile the project, type:
javac -deprecation *.java
To run the program:
java ProxyCache [port number]
Keep in mind that the browser must be configured to localhost and the port number you choose if you are testing locally
We tested our program using heather.cs.ucdavis.edu, heather.cs.ucdavis.edu/matloff.html, and an web page with no response body. We did notice that our program would crash due to the BufferedReader in HttpRequest, which we traced back to being an error with the data sent from the client socket. Additionally, the socket would sometimes error out when sending a response from a web page back to a client, with a "broken pipe" error message.
We implemented the following extentions to our basic proxy: Better Error Handling, Support for POST-method, and Caching.
After getting a response from the server we are sending a request to, we check to see if there is a response body by checking to see if there are any bytes != 0. If there exists bytes other than 0, then there is a body. Additionally, we cached this request so that any further requests to this page will not waste resources attempting to get an empty body.
In HttpRequest.java, we test if we have a post request by checking if the method is "POST". If it is, then we read the header content as usual, but keep track of the content-length in order to get the number of bytes inside the body, which is the POST data. We then check to see if we do have to read the body for POST data. If we do, then we simply parse the data, so it is readily available for ProxyCache to retrieve it to send to the server.
We used a simple HashMap to cache our objects. The key is HttpRequest.toString() method. The value is HttpResponse. We did not include a TTL for our objects in our cache.
private static Map<String, HttpResponse> cache;
When we access a page for the first time, we cache all the requests and responses into our cache. The next time we request those page(s), we immediately search through the cache to see if it exists already. If it does, then we simply return the associated HttpResponse object and return immediately.