Add timestamp support

A new "timestamp" entry for the JSON POST request (/api/v1/store) was added.
The timestamp must be formatted following ISO_OFFSET_DATE_TIME, eg:
YYYY-MM-DDTHH:mm:ss.SSSZ.

The storage request will be denied in case the timestamp is missing, or if
it's more than 5 minutes old (or more than 1 minute into the future).

README.MD

@@ -0,0 +1 @@
+# webMarker Server

src/main/java/net/mindoverflow/webmarker/WebMarker.java

@@ -8,6 +8,9 @@ import net.mindoverflow.webmarker.utils.sql.SQLiteManager;
 import net.mindoverflow.webmarker.webserver.WebApplication;
 import ro.pippo.core.Pippo;
 
+import java.time.ZonedDateTime;
+import java.time.format.DateTimeFormatter;
+
 public class WebMarker {
 
     private static final Messenger msg = new Messenger();
@@ -28,6 +31,10 @@ public class WebMarker {
         pippo.start(port);
         msg.info("Started webserver.");
 
+        ZonedDateTime now = ZonedDateTime.now();
+        DateTimeFormatter formatter = DateTimeFormatter.ISO_OFFSET_DATE_TIME;
+        String nowStr = formatter.format(now);
+        msg.info("Startup timestamp: " + nowStr);
         /* todo: enable to track ram usage
         ScheduledExecutorService exec = Executors.newSingleThreadScheduledExecutor();
         exec.scheduleAtFixedRate(new StatsRunnable(), 0, 5, TimeUnit.SECONDS);

src/main/java/net/mindoverflow/webmarker/utils/FileUtils.java

@@ -8,7 +8,15 @@ public class FileUtils {
 
     public static JsonObject stringToJson(String body)
     {
+        try {
             JsonParser jsonParser = new JsonParser();
             return (JsonObject) jsonParser.parse(body);
+        } catch (Exception e)
+        {
+            // todo: better exception (MalformedJsonException)
+            return null;
         }
     }
+
+    // todo: move more conversion stuff to this class, maybe rename it too?
+}

src/main/java/net/mindoverflow/webmarker/utils/sql/MDatabaseColumn.java

@@ -10,7 +10,8 @@ public enum MDatabaseColumn
     USERNAME(new SQLColumn("username"), SQLDataType.VARCHAR_128),
     PASSWORD(new SQLColumn("password"), SQLDataType.VARCHAR_128),
     USER_UUID(new SQLColumn("userid"), SQLDataType.VARCHAR_128),
-    WEB_DOMAIN(new SQLColumn("domain"), SQLDataType.VARCHAR_128),
+    WEB_DOMAIN(new SQLColumn("domain"), SQLDataType.TEXT),
+    TIMESTAMP_UTC(new SQLColumn("timestamp_utc"), SQLDataType.DATETIME),
 
 
     ;

src/main/java/net/mindoverflow/webmarker/utils/sql/MDatabaseTable.java

@@ -18,6 +18,7 @@ public enum MDatabaseTable
             new ArrayList<>(){{
                 add(MDatabaseColumn.USER_UUID);
                 add(MDatabaseColumn.WEB_DOMAIN);
+                add(MDatabaseColumn.TIMESTAMP_UTC);
 
             }}))
 
@@ -31,3 +32,4 @@ public enum MDatabaseTable
     public SQLTable getTable()
     { return table; }
 }
+

src/main/java/net/mindoverflow/webmarker/utils/sql/MarkerSQLUtils.java

@@ -2,6 +2,8 @@ package net.mindoverflow.webmarker.utils.sql;
 
 import net.mindoverflow.webmarker.utils.Cached;
 
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
 import java.util.List;
 import java.util.UUID;
 
@@ -69,13 +71,19 @@ public class MarkerSQLUtils {
         return result.get(0);
     }
 
-    public static boolean addHistoryRecord(UUID uuid, String url)
+    public static boolean addHistoryRecord(UUID uuid, String url, LocalDateTime timestampUTC)
     {
         String query = "INSERT INTO " + MDatabaseTable.HISTORY.getTable().getTableSQLName() + " ("  +
                 MDatabaseColumn.USER_UUID.getColumn().getColumnSQLName() + ", " +
-                MDatabaseColumn.WEB_DOMAIN.getColumn().getColumnSQLName() + ") VALUES (?, ?);";
+                MDatabaseColumn.WEB_DOMAIN.getColumn().getColumnSQLName() + ", " +
+                MDatabaseColumn.TIMESTAMP_UTC.getColumn().getColumnSQLName() + ") VALUES (?, ?, ?);";
 
-        return Cached.sqlManager.executeUpdate(query, uuid.toString(), url);
+        DateTimeFormatter sqlDateTime = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
+        String timestampSQL = sqlDateTime.format(timestampUTC);
+
+        System.out.println("SQL Timestamp: " + timestampSQL);
+
+        return Cached.sqlManager.executeUpdate(query, uuid.toString(), url, timestampSQL);
 
 
     }

src/main/java/net/mindoverflow/webmarker/webserver/controllers/StorageController.java

@@ -21,6 +21,9 @@ import java.net.MalformedURLException;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
+import java.time.*;
+import java.time.format.DateTimeFormatter;
+import java.time.temporal.ChronoUnit;
 import java.util.UUID;
 
 @Path("/api/v1/store")
@@ -52,7 +55,7 @@ public class StorageController extends Controller
         if(username == null) return;
 
         // Check some stuff about the user
-        if(!userCheckPassed(username)) return;
+        if(!usernameCheckPassed(username)) return;
 
         // Load UUID from username
         UUID uuid = MarkerSQLUtils.getUserUUID(username);
@@ -67,14 +70,46 @@ public class StorageController extends Controller
         if(url == null) return;
 
         // Verify url validity
-        URI confirmedUrl = verifyUrl(url);
+        URI confirmedUrl = stringToURI(url);
         if(confirmedUrl == null) return;
 
-        MarkerSQLUtils.addHistoryRecord(uuid, confirmedUrl.toString());
+        // Load ZonedDateTime from Json body
+        String zonedDateTimeStr = getFromJson(jsonObject, "timestamp");
+        if(zonedDateTimeStr == null) return;
+
+        // Transform String to ZonedDateTime
+        ZonedDateTime timestamp = stringToZDT(zonedDateTimeStr);
+        if(timestamp == null) return;
+        System.out.println("Zoned Timestamp: " + timestamp.toString());
+
+        // Check if the timestamp is too old to be true
+        ZonedDateTime now = ZonedDateTime.now();
+        System.out.println("NOW Timestamp: " + now.toString());
+        if(!dateCheckPassed(timestamp, now)) return;
+
+        // Transform whatever GMT it's on to GMT+0
+        LocalDateTime timestampUTC = LocalDateTime.ofInstant(timestamp.toInstant(), ZoneOffset.UTC);
+        System.out.println("UTC Timestamp: " + timestampUTC.toString());
+
+        MarkerSQLUtils.addHistoryRecord(uuid, confirmedUrl.toString(), timestampUTC);
         routeContext.send("OK!");
 
     }
 
+    // todo: move to safety class?
+    private boolean dateCheckPassed(ZonedDateTime timestamp, ZonedDateTime now)
+    {
+        // allow up to 5 minutes in the past and 1 minute in the future
+        //if(ChronoUnit.MINUTES.between(timestamp, now) > 5) todo: decide
+        if(Duration.between(timestamp, now).getSeconds() >= 5 * 60
+        || Duration.between(timestamp, now).getSeconds() <= -1 * 60)
+        {
+            routeContext.send("Timestamp out of sync!");
+            return false;
+        }
+        return true;
+    }
+
     private JsonElement getJwtFromJson(JsonObject jsonObject)
     {
         JsonElement jwtElement = jsonObject.get("jwt");
@@ -116,7 +151,8 @@ public class StorageController extends Controller
         return claim.asString();
     }
 
-    private boolean userCheckPassed(String username)
+    // todo: move to safety class?
+    private boolean usernameCheckPassed(String username)
     {
         if(!SafetyCheck.isSafeUsername(username))
         {
@@ -146,7 +182,7 @@ public class StorageController extends Controller
         return jsonElement.getAsString();
     }
 
-    private URI verifyUrl(String url)
+    private URI stringToURI(String url)
     {
         try {
             return new URL(url).toURI();
@@ -159,4 +195,11 @@ public class StorageController extends Controller
 
         return null;
     }
+
+    private ZonedDateTime stringToZDT(String timestamp)
+    {
+        DateTimeFormatter formatter = DateTimeFormatter.ISO_OFFSET_DATE_TIME;
+        return ZonedDateTime.parse(timestamp, formatter);
+        // todo: error check
+    }
 }