Add duplicate checking

app.py

@@ -172,11 +172,14 @@ def image():
             c = conn.cursor()
             filename = secure_filename(file.filename)
             file.save(os.path.join(app.config['UPLOAD_FOLDER'], filename))
+            c.execute("SELECT * FROM images WHERE filename=? AND user_id=?", (filename, current_user.get_user_dict()['dn']))
+            row = c.fetchone()
 
-            c.execute("INSERT INTO images (filename, user_id) VALUES (?, ?)", (filename, current_user.get_user_dict()['dn']))
+            if row == None:
+                c.execute("INSERT INTO images (filename, user_id) VALUES (?, ?)", (filename, current_user.get_user_dict()['dn']))
 
-            c.execute("SELECT * FROM images WHERE filename=?", (filename,))
-            row = c.fetchone()
+                c.execute("SELECT * FROM images WHERE filename=? AND user_id=?", (filename, current_user.get_user_dict()['dn']))
+                row = c.fetchone()
             print(row[0])
             conn.commit()
             conn.close()
@@ -237,10 +240,13 @@ def shorten_url():
         c = conn.cursor()
 
         if url is not None and len(url) > 0:
-            c.execute("INSERT INTO links (url, user_id) VALUES (?, ?)", (url, current_user.get_user_dict()['dn']))
-
-            c.execute("SELECT * FROM links WHERE url=?", (url,))
+            c.execute("SELECT * FROM links WHERE url=? AND user_id=?", (url, current_user.get_user_dict()['dn']))
             row = c.fetchone()
+
+            if row == None:
+                c.execute("INSERT INTO links (url, user_id) VALUES (?, ?)", (url, current_user.get_user_dict()['dn']))
+                c.execute("SELECT * FROM links WHERE url=? AND user_id=?", (url, current_user.get_user_dict()['dn']))
+                row = c.fetchone()
             print(row[0])
             conn.commit()
             conn.close()
@@ -260,10 +266,14 @@ def save_paste():
         c = conn.cursor()
 
         if paste is not None and len(paste) > 0:
-            c.execute("INSERT INTO pastes (paste, user_id) VALUES (?, ?)", (paste, current_user.get_user_dict()['dn']))
-
-            c.execute("SELECT * FROM pastes WHERE paste=?", (paste,))
+            c.execute("SELECT * FROM pastes WHERE paste=? AND user_id=?", (paste, current_user.get_user_dict()['dn']))
             row = c.fetchone()
+
+            if row == None:
+                c.execute("INSERT INTO pastes (paste, user_id) VALUES (?, ?)", (paste, current_user.get_user_dict()['dn']))
+
+                c.execute("SELECT * FROM pastes WHERE paste=? AND user_id=?", (paste, current_user.get_user_dict()['dn']))
+                row = c.fetchone()
             print(row[0])
             conn.commit()
             conn.close()