short url generator

app/db.py

@@ -6,7 +6,6 @@
 
 DB_PATH = os.path.join(BASEDIR, 'db.sqlite3')
 
-
 def init_db(db_path):
     """init sqlite database, create sqlite file if needed
 

app/utils.py

@@ -1,23 +1,39 @@
 import argparse
 import textwrap
-from db import ( short_url_exist, get_short_url,
-                    get_long_url_from_db, long_url_exist,
-                    get_short_url_by_long
+from db import (insert_long_url, short_url_exist, get_short_url,
+                get_long_url_from_db, long_url_exist,
+                get_short_url_by_long, insert_short_url,
+                insert_long_url
                 )
+import shortuuid
+from urllib.parse import urlunsplit
+from config import NETLOC, SCHEME
+
+
+class URLExistsError(Exception):
+    def __init__(self, *args):
+        super().__init__(*args)
+        self.message = "This short URL already exists"
+
+
+class URLNotFoundError(Exception):
+    def __init__(self, *args: object):
+        super().__init__(*args)
+        self.message = "This short URL does not exist"
 
 
 def parser():
     parser = argparse.ArgumentParser(
-                                        description="URL shortener app.",
-                                        formatter_class=argparse.RawTextHelpFormatter
-                                    )
+        description="URL shortener app.",
+        formatter_class=argparse.RawTextHelpFormatter
+    )
     parser.add_argument('url', metavar='URL', type=str,
-                            help=textwrap.dedent("""
+                        help=textwrap.dedent("""
                                 Provide URL here.\r
                                 If you want to shorten URL, """ +
-                                """provide it with [--generate] argument.\r
+                                             """provide it with [--generate] argument.\r
                                 If you want to get long URL, """ +
-                                """provide short URL without any other arguments.
+                                             """provide short URL without any other arguments.
                                 """),
                         )
     parser.add_argument('--generate', action='store_true', default=False,
@@ -27,25 +43,60 @@ def parser():
                         help="""Use this argument and cpecify short URL, if you want to use custom short_url."""
                         )
 
-    return parser                
+    return parser
 
 
 class Shortener:
-
 
     @staticmethod
     def get_long_url(short):
+        """ get long url by short url 
+
+        Args:
+            short (str):  short url
+
+        Raises:
+            Exception: Raises Exception when short url does not exists
+
+        Returns:
+            [str]: short url
+        """
         if short_url_exist(short):
             short_inst = get_short_url(short)
             long_inst = get_long_url_from_db(id=short_inst[1])
             return long_inst[1]
         else:
-            raise Exception("This short URL does not exist")
-
+            raise URLNotFoundError
 
     @staticmethod
     def gen_short_url(long):
+        """ Generates short url from long url.
+            If long url exists in DB return existing short url,
+            otherwise generate new short url
+
+        Args:
+            long (str): long url
+
+        Returns:
+            str: short url
+        """
         if long_url_exist(long):
             long_inst = get_long_url_from_db(url=long)
             short_inst = get_short_url_by_long(long_inst[0])
             return short_inst[2]
+        else:
+            uuid = shortuuid.uuid(name=long)[:7]
+            short_url = urlunsplit((SCHEME, NETLOC, uuid, '', ''))
+            long_id = insert_long_url(long)
+            insert_short_url(short_url, long_id)
+            return short_url
+
+    @staticmethod
+    def save_url(short, long):
+        if not short_url_exist(short):
+            if long_url_exist(long):
+                long_inst = get_long_url_from_db(url=long)
+                insert_short_url(short, long_inst[0])
+            return short
+        else:
+            raise URLExistsError

main.py

@@ -1,10 +1,23 @@
+import os
+import sys
+from app.utils import (
+    parser, Shortener,
+    URLExistsError, URLNotFoundError
+)
+from app.db import DB_PATH, init_db
 
 
-
-from app.utils import parser
+def main():
+    if not os.path.exists(DB_PATH):
+        init_db(DB_PATH)
+    args = parser().parse_args()
+    print(args)
+    if not args.generate:
+        try:
+            Shortener.get_long_url(args.url)
+        except URLNotFoundError:
+            print("URL does not exists", file=sys.stderr)
 
 
 if __name__ == '__main__':
-    parser = parser()
-    args = parser.parse_args()
-    print(args)
+    main()

tests/conftest.py

@@ -7,7 +7,7 @@
 
 @pytest.fixture
 def db_path():
-    db_path = os.path.join(tempfile.mkdtemp(), 'db.sqlite3')
+    db_path = os.path.join(tempfile.mkdtemp(), 'db1.sqlite3')
     return db_path
 
 

tests/test_argparse.py

@@ -8,5 +8,5 @@ def test_parser(argparser):
     assert args.url is 'test_url'
     assert args.generate is True
     assert args.short_url is 'short'
-
+    
 

tests/test_main.py

@@ -0,0 +1,29 @@
+from main import main
+from pytest_mock import mocker
+import pytest
+from argparse import Namespace
+from test_db import script
+from unittest import mock
+from app.db import get_db, close_db, init_db
+from argparse import ArgumentParser
+import re
+
+
+
+def test_main_noparams(db_path, mocker):
+    mocker.patch('main.DB_PATH', db_path)
+    with pytest.raises(SystemExit):
+        main()
+
+def test_main_short_url(db_path, argparser, mocker, capsys):
+    mocker.patch('main.DB_PATH', db_path)
+    init_db(db_path=db_path)
+    with mock.patch('app.db.DB_PATH', db_path):
+        db = get_db()
+        db.executescript(script)
+        args = argparser.parse_args(['on.ln'])    
+        parser = mocker.patch('argparse.ArgumentParser.parse_args', return_value=args)
+        main()
+        captured = capsys.readouterr()
+        print(captured)
+        assert 'URL does not exists\n' == captured.err

tests/test_utils.py

@@ -1,4 +1,6 @@
-from app.utils import Shortener
+from os import name
+from urllib.parse import urlencode
+from app.utils import Shortener, URLNotFoundError, URLExistsError
 from tests.test_db import script, manager_mock
 import pytest
 from unittest import mock
@@ -7,7 +9,7 @@
 def  test_get_long_url(db_mock):
     db_mock.executescript(script)
     with manager_mock(db_mock, 'db.get_db', 'db.db_manager'):
-        with pytest.raises(Exception, match=r".* URL does .*"):
+        with pytest.raises(URLNotFoundError, match=r".* URL does not .*"):
             Shortener.get_long_url('raise')
         inst = Shortener.get_long_url('goo.gl')
         assert type(inst) is str
@@ -19,3 +21,13 @@ def test_get_long_url(db_mock):
         inst = Shortener.gen_short_url('https://www.google.com/')
         assert type(inst) is str
         assert inst == 'goo.gl'
+        inst = Shortener.gen_short_url('http://www.onliner.by')
+        assert type(inst) is str
+
+def test_save_url(db_mock):
+    db_mock.executescript(script)
+    with manager_mock(db_mock, 'db.get_db', 'db.db_manager'):
+        with pytest.raises(URLExistsError):
+            Shortener.save_url('goo.gl', 'https://www.google.com/')
+        short = Shortener.save_url('on.by/ptrer', 'http://www.onliner.by')
+        assert isinstance(short, str)