app/utils.py

   1 # Content DB
   2 # Copyright (C) 2018  rubenwardy
   3 #
   4 # This program is free software: you can redistribute it and/or modify
   5 # it under the terms of the GNU General Public License as published by
   6 # the Free Software Foundation, either version 3 of the License, or
   7 # (at your option) any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
  16
  17
  18 from flask import request, flash, abort, redirect
  19 from flask_user import *
  20 from flask_login import login_user, logout_user
  21 from .models import *
  22 from . import app
  23 import random, string, os, imghdr
  24 from urllib.parse import urljoin
  25
  26 def abs_url_for(path, **kwargs):
  27         scheme = "https" if app.config["BASE_URL"][:5] == "https" else "http"
  28         return url_for(path, _external=True, _scheme=scheme, **kwargs)
  29
  30 def abs_url(path):
  31         return urljoin(app.config["BASE_URL"], path)
  32
  33 def get_int_or_abort(v, default=None):
  34         try:
  35                 return int(v or default)
  36         except ValueError:
  37                 abort(400)
  38
  39 def getExtension(filename):
  40         return filename.rsplit(".", 1)[1].lower() if "." in filename else None
  41
  42 def isFilenameAllowed(filename, exts):
  43         return getExtension(filename) in exts
  44
  45 ALLOWED_IMAGES = set(["jpeg", "png"])
  46 def isAllowedImage(data):
  47         return imghdr.what(None, data) in ALLOWED_IMAGES
  48
  49 def shouldReturnJson():
  50         return "application/json" in request.accept_mimetypes and \
  51                         not "text/html" in request.accept_mimetypes
  52
  53 def randomString(n):
  54         return ''.join(random.choice(string.ascii_lowercase + \
  55                         string.ascii_uppercase + string.digits) for _ in range(n))
  56
  57 def doFileUpload(file, fileType, fileTypeDesc):
  58         if not file or file is None or file.filename == "":
  59                 flash("No selected file", "danger")
  60                 return None, None
  61
  62         assert os.path.isdir(app.config["UPLOAD_DIR"]), "UPLOAD_DIR must exist"
  63
  64         allowedExtensions = []
  65         isImage = False
  66         if fileType == "image":
  67                 allowedExtensions = ["jpg", "jpeg", "png"]
  68                 isImage = True
  69         elif fileType == "zip":
  70                 allowedExtensions = ["zip"]
  71         else:
  72                 raise Exception("Invalid fileType")
  73
  74         ext = getExtension(file.filename)
  75         if ext is None or not ext in allowedExtensions:
  76                 flash("Please upload " + fileTypeDesc, "danger")
  77                 return None, None
  78
  79         if isImage and not isAllowedImage(file.stream.read()):
  80                 flash("Uploaded image isn't actually an image", "danger")
  81                 return None, None
  82
  83         file.stream.seek(0)
  84
  85         filename = randomString(10) + "." + ext
  86         filepath = os.path.join(app.config["UPLOAD_DIR"], filename)
  87         file.save(filepath)
  88         return "/uploads/" + filename, filepath
  89
  90 def make_flask_user_password(plaintext_str):
  91         # http://passlib.readthedocs.io/en/stable/modular_crypt_format.html
  92         # http://passlib.readthedocs.io/en/stable/lib/passlib.hash.bcrypt.html#format-algorithm
  93         # Flask_User stores passwords in the Modular Crypt Format.
  94         # https://github.com/lingthio/Flask-User/blob/master/flask_user/user_manager__settings.py#L166
  95         #   Note that Flask_User allows customizing password algorithms.
  96         #   USER_PASSLIB_CRYPTCONTEXT_SCHEMES defaults to bcrypt but if
  97         #   default changes or is customized, the code below needs adapting.
  98         # Individual password values will look like:
  99         #   $2b$12$.az4S999Ztvy/wa3UdQvMOpcki1Qn6VYPXmEFMIdWQyYs7ULnH.JW
 100         #   $XX$RR$SSSSSSSSSSSSSSSSSSSSSSHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
 101         # $XX : Selects algorithm (2b is bcrypt).
 102         # $RR : Selects bcrypt key expansion rounds (12 is 2**12 rounds).
 103         # $SSS... : 22 chars of (random, per-password) salt
 104         #  HHH... : 31 remaining chars of password hash (note no dollar sign)
 105         import bcrypt
 106         plaintext = plaintext_str.encode("UTF-8")
 107         password = bcrypt.hashpw(plaintext, bcrypt.gensalt())
 108         if isinstance(password, str):
 109                 return password
 110         else:
 111                 return password.decode("UTF-8")
 112
 113 def loginUser(user):
 114         def _call_or_get(v):
 115                 if callable(v):
 116                         return v()
 117                 else:
 118                         return v
 119
 120         # User must have been authenticated
 121         if not user:
 122                 return False
 123
 124         if user.rank == UserRank.BANNED:
 125                 flash("You have been banned.", "danger")
 126                 return False
 127
 128         user.active = True
 129         if not user.rank.atLeast(UserRank.NEW_MEMBER):
 130                 user.rank = UserRank.MEMBER
 131
 132         db.session.commit()
 133
 134         # Check if user account has been disabled
 135         if not _call_or_get(user.is_active):
 136                 flash("Your account has not been enabled.", "danger")
 137                 return False
 138
 139         # Use Flask-Login to sign in user
 140         login_user(user, remember=True)
 141         signals.user_logged_in.send(current_app._get_current_object(), user=user)
 142
 143         flash("You have signed in successfully.", "success")
 144
 145         return True
 146
 147
 148 def rank_required(rank):
 149         def decorator(f):
 150                 @wraps(f)
 151                 def decorated_function(*args, **kwargs):
 152                         if not current_user.is_authenticated:
 153                                 return redirect(url_for("user.login"))
 154                         if not current_user.rank.atLeast(rank):
 155                                 abort(403)
 156
 157                         return f(*args, **kwargs)
 158
 159                 return decorated_function
 160         return decorator
 161
 162 def getPackageByInfo(author, name):
 163         user = User.query.filter_by(username=author).first()
 164         if user is None:
 165                 abort(404)
 166
 167         package = Package.query.filter_by(name=name, author_id=user.id, soft_deleted=False).first()
 168         if package is None:
 169                 abort(404)
 170
 171         return package
 172
 173 def is_package_page(f):
 174         @wraps(f)
 175         def decorated_function(*args, **kwargs):
 176                 if not ("author" in kwargs and "name" in kwargs):
 177                         abort(400)
 178
 179                 package = getPackageByInfo(kwargs["author"], kwargs["name"])
 180
 181                 del kwargs["author"]
 182                 del kwargs["name"]
 183
 184                 return f(package=package, *args, **kwargs)
 185
 186         return decorated_function
 187
 188 def triggerNotif(owner, causer, title, url):
 189         if owner.rank.atLeast(UserRank.NEW_MEMBER) and owner != causer:
 190                 Notification.query.filter_by(user=owner, url=url).delete()
 191                 notif = Notification(owner, causer, title, url)
 192                 db.session.add(notif)
 193
 194 def clearNotifications(url):
 195         if current_user.is_authenticated:
 196                 Notification.query.filter_by(user=current_user, url=url).delete()
 197                 db.session.commit()
 198
 199
 200 YESES = ["yes", "true", "1", "on"]
 201
 202 def isYes(val):
 203         return val and val.lower() in YESES
 204
 205
 206 def isNo(val):
 207         return val and not isYes(val)