DS_project_PUBLISH

Here is a basic implementation for PUBLISH command: Resource.java--------------------------------------------------------------------------------------------------------- package EZShare; import java.net.*; public class Resource { public String name; public String description; public String[] tags; public URI uri; private String channel; public String owner; public String ezserver; //public HashMap<String, Object> primarykey; // signals for string error??? //public boolean stringerror; //private String rule; public Resource() { name = ""; description = ""; tags= new String[]{}; uri = null; channel = ""; owner = ""; ezserver = "localhost:8080"; //rule = ""; //primarykey = null; } public String getChannel() { return channel; } public void changeChannel(String word) { channel = word; } /* public void primaryKey(String Owner, String Channel, URI Uri) { primarykey.put("owner",Owner); primarykey.put("channel",Channel); primarykey.put("uri",Uri); } public void breakRule() { rule = "broken"; } */ } Client.java------------------------------------------------------------------------------------------------------------ package EZShare; import java.io.DataInputStream; import java.io.DataOutputStream; import java.io.IOException; import java.net.ServerSocket; import java.net.Socket; import java.net.URI; import java.net.URISyntaxException; import java.net.UnknownHostException; import java.util.Arrays; import org.json.simple.JSONArray; import org.json.simple.JSONObject; import org.json.simple.parser.JSONParser; import org.json.simple.parser.ParseException; import com.google.gson.Gson; import org.apache.commons.cli.CommandLine; import org.apache.commons.cli.CommandLineParser; import org.apache.commons.cli.Options; import org.apache.commons.cli.DefaultParser; import org.apache.commons.cli.HelpFormatter; public class Client { private static String ip = "localhost"; // 127.0.0.1 private static int port = 8080; public static void main(String[] args) { try(Socket socket = new Socket(ip,port)) { DataInputStream input = new DataInputStream(socket.getInputStream()); DataOutputStream output = new DataOutputStream(socket.getOutputStream()); output.writeUTF("Hello server"); output.flush(); Options options = new Options(); JSONObject command = new JSONObject(); // client command line arguments options.addOption("channel",true,"channel"); options.addOption("debug",false,"print debug information"); options.addOption("description",true,"resource description"); options.addOption("exchange",false,"exchange server list with server"); options.addOption("fetch",false,"fetch resources from server"); options.addOption("host",true,"server host, a domain name or IP address"); options.addOption("name",true,"resource name"); options.addOption("owner",true,"owner"); options.addOption("port",true,"server port, an integer"); options.addOption("publish",false,"publish resource on server"); options.addOption("query",false,"query for resources from server"); options.addOption("remove",false,"remove resource from server"); options.addOption("secret",true,"secret"); options.addOption("servers",true,"server list, host1:port1,host2:port2,..."); options.addOption("share",false,"share resource on server"); options.addOption("tags",true,"resource tags, tag1,tag2,tag3,..."); options.addOption("uri",true,"resource URI"); //options.addOption("email",true, "input email address"); CommandLineParser parser = new DefaultParser(); CommandLine cmd = null; try { cmd = parser.parse(options,args); } catch (org.apache.commons.cli.ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } Resource resource = new Resource(); JSONObject send = new JSONObject(); // PUBLISH command if(cmd.hasOption("publish")){ if(cmd.hasOption("name")) { resource.name = cmd.getOptionValue("name"); } if(cmd.hasOption("description")) { resource.description = cmd.getOptionValue("description"); } if(cmd.hasOption("tags")) { resource.tags = cmd.getOptionValue("tags").split(","); System.out.println(Arrays.toString(resource.tags)); /* for(String tag:resource.tags) { if (tag.startsWith(" ") || tag.endsWith(" ") || tag.contains("\0")) { System.out.println("The server may silently remove these things from receive resource descriptions"); } }*/ } if(cmd.hasOption("channel")) { // "" is though of as public channel???????????????? resource.changeChannel(cmd.getOptionValue("channel")); } if(cmd.hasOption("owner")) { resource.owner = cmd.getOptionValue("owner"); /* if (resource.owner.startsWith(" ") || resource.owner.endsWith(" ") || resource.owner.contains("\0") || resource.owner.equals("*")) { System.out.println("The server may silently remove these things from receive resource descriptions"); }*/ } // Put resource into JSON command //resource.primaryKey(resource.owner, resource.getChannel(), resource.uri); /* Gson gson = new Gson(); String send = gson.toJson(resource); command.put("resource", send); */ send.put("name", resource.name); send.put("description",resource.description); //send.put("tags", Arrays.toString(resource.tags)); JSONArray arr = new JSONArray(); for(String tag: resource.tags) { arr.add(tag); } send.put("tags", arr); send.put("channel", resource.getChannel()); send.put("owner", resource.owner); send.put("ezserver", resource.ezserver); command.put("resource", send); command.put("command", "PUBLISH"); } // REMOVE COMMAND // MANDANTORY URI if(cmd.hasOption("uri")) { resource.uri = new URI(cmd.getOptionValue("uri")); send.put("uri", resource.uri.toString()); } output.writeUTF(command.toJSONString()); JSONParser js_parser = new JSONParser(); //String message = input.readUTF(); while(true){ if(input.available() > 0) { JSONObject result = (JSONObject) js_parser.parse(input.readUTF()); System.out.println("Received from Server: "+ result.get("results")); } } } catch (UnknownHostException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (URISyntaxException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } Server.java---------------------------------------------------------------------------------------------------------------------- package EZShare; import java.io.DataInputStream; import java.io.DataOutputStream; import java.io.IOException; import java.net.ServerSocket; import java.net.Socket; import java.text.ParseException; import java.util.ArrayList; import java.util.List; import javax.net.ServerSocketFactory; import org.apache.commons.cli.CommandLine; import org.apache.commons.cli.CommandLineParser; import org.apache.commons.cli.DefaultParser; import org.apache.commons.cli.Options; import org.json.simple.JSONObject; import org.json.simple.parser.JSONParser; public class Server { private static int port = 8080; private static String advertisedhostname; private static String secret = "5uv1ii7ec362me7hkch3s7l5c4"; private static int exchangeinterval = 600; // seconds private static List<JSONObject> resourcelist = new ArrayList<JSONObject>(); public static void main(String[] args) { ServerSocketFactory factory = ServerSocketFactory.getDefault(); try(ServerSocket server = factory.createServerSocket(port)) { boolean isActive = true; Options options = new Options(); JSONObject command = new JSONObject(); // server command line arguments options.addOption("advertisedhostname",true,"advertised host name"); options.addOption("connectionintervallimit",true,"connection interval limit in seconds"); options.addOption("exchangeinterval",true,"exchange interval in seconds"); options.addOption("port",true,"server port, an integer"); options.addOption("secret",true,"secret"); options.addOption("debug",false,"print debug information"); //options.addOption("email",true, "input email address"); CommandLineParser parser = new DefaultParser(); CommandLine cmd = null; try { cmd = parser.parse(options,args); } catch (org.apache.commons.cli.ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } while(isActive){ Socket Client = server.accept(); System.out.println("A client has connected."); Thread r =new Thread(()-> serverClient(Client)); r.start(); } } catch (IOException e) { e.printStackTrace(); } } private static JSONObject parseCommand(JSONObject command) { int result = 0; //Resource resource = new Resource(); JSONParser parser = new JSONParser(); JSONObject resource = new JSONObject(); JSONObject message = new JSONObject(); boolean publisherror = false; if(command.containsKey("command")) { if(command.get("command").equals("PUBLISH")) { /* try { resource = (JSONObject) parser.parse((String) command.get("resource")); } catch (org.json.simple.parser.ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } */ resource = (JSONObject) command.get("resource"); // Publishing a resource with the same channel and URI but different owner is not allowed. for (JSONObject r: resourcelist) { if(resource.get("channel") == r.get("channel")&&resource.get("uri") == r.get("uri") && resource.get("owner") != r.get("owner")) { publisherror = true; } } if (resource.get("uri") == null) { message.put("response", "error"); message.put("errorMessage", "missing resource"); } else if (((String) resource.get("name")).startsWith(" ") || ((String) resource.get("name")).endsWith(" ") || ((String) resource.get("name")).contains("\0")) { message.put("response", "error"); message.put("errorMessage", "invalid resource"); } else if (((String) resource.get("description")).startsWith(" ") || ((String) resource.get("description")).endsWith(" ") || ((String) resource.get("description")).contains("\0")) { message.put("response", "error"); message.put("errorMessage", "invalid resource"); } /*else if (resource.name.startsWith(" ") || resource.name.endsWith(" ") || resource.name.contains("\0")) { message.put("response", "error"); message.put("errorMessage", "invalid resource"); }*/ else if (((String) resource.get("channel")).startsWith(" ") || ((String) resource.get("channel")).endsWith(" ") || ((String) resource.get("channel")).contains("\0")) { message.put("response", "error"); message.put("errorMessage", "invalid resource"); } else if (((String) resource.get("owner")).startsWith(" ") || ((String) resource.get("owner")).endsWith(" ") || ((String) resource.get("owner")).contains("\0") || ((String) resource.get("owner")).equals("*")) { message.put("response", "error"); message.put("errorMessage", "invalid resource"); } else if (publisherror == true) { message.put("response", "error"); message.put("errorMessage", "cannot publish resource"); } else if (resource.get("uri").toString().contains("file")) { //The URI must be present, must be absolute and cannot be a file scheme message.put("response", "error"); message.put("errorMessage", "cannot publish resource"); } else { // check if the primary key is same with exists // if yes, overwrite for (JSONObject r: resourcelist) { if (r.get("owner").equals(resource.get("owner"))&&r.get("channel").equals(resource.get("channel")) &&r.get("uri")==(resource.get("uri"))) { resourcelist.remove(r); } } resourcelist.add(resource); message.put("response", "success"); } } else { // there are other commands rather than "publish", "remove", ... message.put("response", "error"); message.put("errorMessage", "invalid command"); } // there is no command } else { message.put("response", "error"); message.put("errorMessage", "missing or incorrect type for command"); } return message; } private static void serverClient(Socket client) { try(Socket clientSocket = client) { JSONParser parser = new JSONParser(); DataInputStream input = new DataInputStream(clientSocket.getInputStream()); DataOutputStream output = new DataOutputStream(clientSocket.getOutputStream()); System.out.println("Client: " + input.readUTF()); //output.writeUTF("Message received."); while(true) { if(input.available() > 0) { JSONObject command = (JSONObject)parser.parse(input.readUTF()); System.out.println(command); JSONObject message = parseCommand(command); JSONObject results = new JSONObject(); results.put("results", message); output.writeUTF(results.toJSONString()); } } } catch (IOException e) { e.printStackTrace(); } catch (org.json.simple.parser.ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } --------------------------------------------------------------------------------------------------------------------------------- Example Arguments for Client.java: -publish -name "Unibsite" -description "The main page for the University of Melbourne" -uri http://www.unimelb.edu.au -tags web,html --------------------------------------------------------------------------------------------------------------------------------- One thing to be noticed is that "String values must not contain the "\0" character, nor start or end with whitespace. The server may silently remove such characters or may consider the resource invalid if such things are found (this is the same for all commands)." I adopt the latter way to handle this problem, which is considered to be a invalid resource, and will not be published successfully. There may be some hidden problems that not found by me, I am trying to find.