4 files changed, 216 insertions, 0 deletions
diff --git a/api/util/authentication.py b/api/util/authentication.py
new file mode 100644
index 0000000..43b147a
--- /dev/null
+++ b/api/util/authentication.py
@@ -0,0 +1,97 @@
+import random
+import bcrypt
+from fastapi import Depends, HTTPException, status, Request, Cookie
+from fastapi.security import OAuth2PasswordBearer
+from fastapi.responses import Response
+from jwt.exceptions import InvalidTokenError, ExpiredSignatureError
+from datetime import datetime, timedelta
+import jwt
+
+from api.util.db_dependency import get_db
+from sqlalchemy.orm import Session
+from api.schemas.auth_schemas import *
+from models import User as UserModel
+
+secret_key = random.randbytes(32)
+algorithm = "HS256"
+oauth2_scheme = OAuth2PasswordBearer(tokenUrl="api/auth/token")
+
+"""
+Helper functions for authentication
+"""
+
+
+def verify_password(plain_password, hashed_password):
+    return bcrypt.checkpw(
+        plain_password.encode("utf-8"), hashed_password.encode("utf-8")
+    )
+
+
+def get_user(db, username: str):
+    """
+    Get the user object from the database
+    """
+    user = db.query(UserModel).filter(UserModel.username == username).first()
+    if user:
+        return UserInDB(**user.__dict__)
+
+
+def authenticate_user(db, username: str, password: str):
+    """
+    Determine if the correct username and password were provided
+    If so, return the user object
+    """
+    user = get_user(db, username)
+    if not user:
+        return False
+    if not verify_password(password, user.hashed_password):
+        print("WHY")
+        return False
+    return user
+
+
+def create_access_token(data: dict, expires_delta: timedelta):
+    """
+    Return an encoded JWT token with the given data
+    """
+    to_encode = data.copy()
+    expire = datetime.utcnow() + expires_delta
+    to_encode.update({"exp": expire})
+    encoded_jwt = jwt.encode(to_encode, secret_key, algorithm=algorithm)
+    return encoded_jwt
+
+
+def raise_unauthorized():
+    raise HTTPException(
+        status_code=status.HTTP_401_UNAUTHORIZED,
+        detail="Could not validate credentials",
+        headers={"WWW-Authenticate": "Bearer"},
+    )
+
+
+async def get_current_user(
+    request: Request,
+    db=Depends(get_db),
+):
+    """
+    Return the current user object if the access token is valid
+
+    All failed attempts will return a 401
+    """
+    token = request.cookies.get("access_token")
+
+    try:
+        payload = jwt.decode(token, secret_key, algorithms=[algorithm])
+        id: int = payload.get("sub")
+        username: str = payload.get("username")
+        if not id or not username:
+            return raise_unauthorized()
+
+    except InvalidTokenError:
+        return raise_unauthorized()
+
+    user = get_user(db, username)
+    if user is None:
+        return raise_unauthorized()
+
+    return user
diff --git a/api/util/check_password_reqs.py b/api/util/check_password_reqs.py
new file mode 100644
index 0000000..dcb9bf8
--- /dev/null
+++ b/api/util/check_password_reqs.py
@@ -0,0 +1,26 @@
+from fastapi import HTTPException, status
+
+
+def check_password_reqs(password: str):
+    """
+    Make sure the entered password meets the security requirements:
+        1. At least 8 characters
+        2. At least one digit
+        3. At least one uppercase letter
+    """
+    if len(password) < 8:
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail="Password must be at least 8 characters",
+        )
+    if not any(char.isdigit() for char in password):
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail="Password must contain at least one digit",
+        )
+    if not any(char.isupper() for char in password):
+        raise HTTPException(
+            status_code=status.HTTP_400_BAD_REQUEST,
+            detail="Password must contain at least one uppercase letter",
+        )
+    return
diff --git a/api/util/db_dependency.py b/api/util/db_dependency.py
new file mode 100644
index 0000000..a6734ea
--- /dev/null
+++ b/api/util/db_dependency.py
@@ -0,0 +1,9 @@
+from database import SessionLocal
+
+
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()
diff --git a/api/util/log.py b/api/util/log.py
new file mode 100644
index 0000000..58a56f9
--- /dev/null
+++ b/api/util/log.py
@@ -0,0 +1,84 @@
+import requests
+import datetime
+from ua_parser import user_agent_parser
+
+from database import SessionLocal
+import config
+from models import Link, Log
+
+"""
+Create a new log whenever a link is visited
+"""
+
+
+def ip_to_location(ip):
+    if not config.IP_TO_LOCATION:
+        return "-, -", "-"
+
+    url = f"https://api.ip2location.io/?key={config.API_KEY}&ip={ip}"
+    response = requests.get(url)
+    data = response.json()
+
+    if response.status_code != 200:
+        config.LOG.error(
+            "Error with IP2Location API. Perhaps the API is down."
+        )
+        return "-, -", "-"
+
+    if "error" in data:
+        config.LOG.error(
+            "Error with IP2Location API. Likely wrong API key or insufficient"
+            " funds."
+        )
+        return "-, -", "-"
+
+    location = ""
+    # Sometimes a certain name may not be present, so always check
+    if "city_name" in data:
+        location += data["city_name"]
+
+    if "region_name" in data:
+        location += f', {data["region_name"]}'
+
+    if "country_name" in data:
+        location += f', {data["country_name"]}'
+
+    isp = data["as"]
+    return location, isp
+
+
+def log(link, ip, user_agent):
+    db = SessionLocal()
+
+    # Get the redirect link and owner of the link
+    redirect_link, owner = (
+        db.query(Link.redirect_link, Link.owner)
+        .filter(Link.link == link)
+        .first()
+    )
+
+    # Get the location and ISP of the user
+    location, isp = ip_to_location(ip)
+
+    ua_string = user_agent_parser.Parse(user_agent)
+    browser = ua_string["user_agent"]["family"]
+    os = f'{ua_string["os"]["family"]} {ua_string["os"]["major"]}'
+
+    # Create the log and commit it to the database
+    new_log = Log(
+        owner=owner,
+        link=link,
+        timestamp=datetime.datetime.utcnow(),
+        ip=ip,
+        location=location,
+        browser=browser,
+        os=os,
+        user_agent=user_agent,
+        isp=isp,
+    )
+    db.add(new_log)
+    db.commit()
+    db.close()
+
+    # Return the redirect link in order to properly redirect the user
+    return redirect_link