coverage 100%

backend/.gitignore

@@ -1,6 +1,11 @@
 venv
-sources
-uploads
+
+sources/
+!sources/sample.hackthehill
+
+uploads/
+!uploads/sample.txt
+
 __pycache__
 .coverage
 .idea

backend/code/file_tokenizer.py

@@ -8,6 +8,8 @@
 
 from pathlib import Path
 
+from config import SOURCES_FOLDER
+
 
 class SenderTokenizer:
     """
@@ -31,6 +33,7 @@ def hash_file_blocks(self, block_size=512):
         be used to hide the nature of the file in communication
         """
 
+        hackthehill_file = Path(self.file_path).stem + ".hackthehill"
         file_size: int = os.path.getsize(self.file_path)
         num_blocks = (file_size + block_size -
                       1) // block_size  # Round up division
@@ -58,8 +61,7 @@ def hash_file_blocks(self, block_size=512):
 
         hash_block = json.dumps(header, indent=2)
 
-        with open("./sources/" + Path(self.file_path).stem + ".hackthehill",
-                  'w', encoding="utf-8") as f:
+        with open(os.path.join(SOURCES_FOLDER, hackthehill_file), 'w', encoding="utf-8") as f:
             f.write(hash_block)
 
         return hashlib.sha256(json.dumps(header).encode('utf-8')).hexdigest()

backend/code/main.py

@@ -6,7 +6,7 @@
 import io
 import json
 
-from code.config import UPLOAD_FOLDER
+from config import UPLOADS_FOLDER
 from code.utils import get_filename_by_file_id, custom_hash
 from code.p2p_client import P2PClient
 from code.file_tokenizer import SenderTokenizer
@@ -20,8 +20,8 @@
 CORS(app)
 
 # Ensure the upload directory exists
-if not os.path.exists(UPLOAD_FOLDER):
-    os.makedirs(UPLOAD_FOLDER)
+if not os.path.exists(UPLOADS_FOLDER):
+    os.makedirs(UPLOADS_FOLDER)
 
 fileData = {}
 

backend/code/p2p_client.py

@@ -13,7 +13,7 @@
 
 from code.utils import get_filename_by_file_id
 from code.file_tokenizer import ReceiverTokenizer
-from code.config import DISCOVERY_PORT, CHAT_PORT, MAX_UDP_PACKET, DISCOVERY_ADDRESS
+from config import DISCOVERY_PORT, CHAT_PORT, MAX_UDP_PACKET, DISCOVERY_ADDRESS
 
 
 class P2PClient:

backend/code/utils.py

@@ -10,10 +10,12 @@
 from pathlib import Path
 from typing import Optional
 
+from config import SOURCES_FOLDER, UPLOADS_FOLDER
+
 
 def custom_hash(encode_input):
     """
-    Using the hashlib sha256 encoding, we specifically hash the utf-8 encoding for 
+    Using the hashlib sha256 encoding, we specifically hash the utf-8 encoding for
     text files. This is our custom hash function we use in the entire project, we should not
     use the inbuilt hash() function
     """
@@ -24,11 +26,11 @@ def custom_hash(encode_input):
 def find_file(directory: str, filename: str) -> Optional[str]:
     """
     Helper function for get_filename_by_file_id
-    
+
     Given a directory and a filename, check if the directory exists, and if the file
     exists inside the given directory. If yes, return the file name, otherwise return
     None
-    
+
     :param directory: str
     :param filename: str
     :returns: Either string or None
@@ -37,23 +39,28 @@ def find_file(directory: str, filename: str) -> Optional[str]:
     if os.path.exists(directory):
         for file in os.listdir(directory):
             name, _ = os.path.splitext(file)
-            if name == filename:
+            if name == Path(filename).stem:
                 return file
     return None
 
 
-def get_filename_by_file_id(file_id):
+def get_filename_by_file_id(file_id: str) -> Optional[tuple[str, str]]:
     """
-    TODO
+    Given the unique file id we have, we check if original file which is related to
+    that particular file id exists or not. Returns None if file does not exist in that directory
+    Note that by our convention, .hackthehill files exist in backend/sources and the
+    original files exist in backend/uploads.
+
+    :param file_id: str
+    :returns: tuple[str, str] | None
     """
 
-    for fingerprint_file_name in os.listdir("sources"):
-        with open(os.path.join("sources", fingerprint_file_name), "r", encoding="utf-8") as f:
-            file_fingerprint_content = f.read()
+    for hackthehill_file in os.listdir(SOURCES_FOLDER):
+        with open(os.path.join(SOURCES_FOLDER, hackthehill_file), "r", encoding="utf-8") as f:
+            hackthehill_file_content = f.read()
 
-            if file_id == custom_hash(file_fingerprint_content):
-                file_name = find_file(
-                    "uploads", Path(fingerprint_file_name).stem)
-                if file_name is not None:
-                    return [file_name, fingerprint_file_name]
+            if file_id == custom_hash(hackthehill_file_content):
+                original_file_name = find_file(UPLOADS_FOLDER, hackthehill_file)
+                if original_file_name is not None:
+                    return original_file_name, hackthehill_file
     return None

backend/config.py

@@ -0,0 +1,19 @@
+"""
+Global variables for the project
+
+Since the file contains actual directory names, it must be at the root of backend
+"""
+
+import os.path
+
+DISCOVERY_PORT = 5000
+CHAT_PORT = 5001
+MAX_UDP_PACKET = 65507
+DISCOVERY_ADDRESS = '192.168.181.255'
+
+BACKEND_FOLDER = os.path.dirname(os.path.abspath(__file__))
+
+UPLOADS_FOLDER = os.path.join(BACKEND_FOLDER, "uploads")
+SOURCES_FOLDER = os.path.join(BACKEND_FOLDER, "sources")
+CODE_FOLDER = os.path.join(BACKEND_FOLDER, "code")
+TEST_FOLDER = os.path.join(BACKEND_FOLDER, "test")

backend/sources/sample.hackthehill

@@ -0,0 +1 @@
+Adding the file just so that sources folder is recognized via github

backend/sourcestest.hackthehill

@@ -0,0 +1,9 @@
+{
+  "header": {
+    "file_name": "test.txt",
+    "file_size": 0,
+    "number_of_blocks": 0,
+    "block_size": 512
+  },
+  "blocks": {}
+}

backend/test/test_utils.py

@@ -2,22 +2,27 @@
 Testing the Utilities class
 """
 import hashlib
+import os.path
+import pathlib
 import unittest
-from code.utils import find_file, custom_hash
+
+from code.file_tokenizer import SenderTokenizer
+from config import SOURCES_FOLDER, CODE_FOLDER, UPLOADS_FOLDER
+from code.utils import find_file, custom_hash, get_filename_by_file_id
 
 
 class TestUtils(unittest.TestCase):
     """
     Utilities class functions are generic and widely used. Their implementation is very important.
     """
-    
+
     def test_custom_hash(self):
         """
         We have our own implementation for hashing utf-8 format encoding
         """
-        
+
         encoded_input = "Hi Mom"
-        
+
         self.assertEqual(custom_hash(encoded_input), hashlib.sha256(encoded_input.encode("utf-8")).hexdigest())
 
     def test_find_file_with_garbage_file_name_returns_none(self):
@@ -33,13 +38,54 @@ def test_find_file_with_garbage_directory_name_returns_none(self):
         """
 
         self.assertEqual(find_file("random_directory", "uploads.txt"), None)
-    
+
     def test_find_file_with_proper_director_and_file_returns_filename(self):
         """
         If a file and directory exists, and file exists inside the directory, return the 
         filename
         """
-
-        self.assertEqual(find_file("code", "utils"), "utils.py")
-
-
+
+        self.assertEqual(find_file(CODE_FOLDER, "utils.py"), "utils.py")
+
+    def test_get_filename_by_file_id_with_no_matching_id_returns_none(self):
+        """
+        If none of the hashed ids match with the file id, we should return None
+        """
+
+        testing_file = os.path.join(UPLOADS_FOLDER, "test_get_filename_by_file_id_with_no_matching_id_returns_none.txt")
+        message = "test_get_filename_by_file_id_with_no_matching_id_returns_none"
+
+        with open(testing_file, "x", encoding="utf-8") as f:
+            f.write(message)
+            file_id = "random-file-id"
+
+            self.assertEqual(get_filename_by_file_id(file_id), None)
+
+        os.remove(testing_file)
+
+    def test_get_filename_by_file_id_with_matching_id_returns_tuple(self):
+        """
+        If the hashed id is the same as the hash of .hackthehill file, we should return the tuple of filenames
+        """
+
+        testing_file = os.path.join(UPLOADS_FOLDER,
+                                    "test_get_filename_by_file_id_with_matching_id_returns_tuple.txt")
+        hackthehill_file = os.path.join(SOURCES_FOLDER,
+                                        "test_get_filename_by_file_id_with_matching_id_returns_tuple.hackthehill")
+
+        hashed_file = SenderTokenizer(testing_file)
+        message = "test_get_filename_by_file_id_with_matching_id_returns_tuple"
+
+        with open(testing_file, "x", encoding="utf-8") as f:
+            f.write(message)
+            hashed_file.hash_file_blocks()
+
+            with open(hackthehill_file, "r", encoding="utf-8") as f:
+                hackthehill_file_content = f.read()
+                file_id = custom_hash(hackthehill_file_content)
+
+            self.assertEqual(get_filename_by_file_id(file_id), (os.path.basename(testing_file),
+                                                                os.path.basename(hackthehill_file)))
+
+        os.remove(testing_file)
+        os.remove(hackthehill_file)

backend/uploads/sample.txt

@@ -0,0 +1 @@
+Adding the file just so that uploads folder is recognized via github

setup.sh

@@ -12,5 +12,7 @@ cd "$backendDir"
 python3.9 -m venv venv 
 source venv/bin/activate 
 pip install -r requirements.txt
+mkdir sources
+mkdir uploads
 
 cd "$currentDir"