app/utils.py

   1 # ContentDB
   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         if v is None:
  35                 return default
  36
  37         try:
  38                 return int(v or default)
  39         except ValueError:
  40                 abort(400)
  41
  42 def getExtension(filename):
  43         return filename.rsplit(".", 1)[1].lower() if "." in filename else None
  44
  45 def isFilenameAllowed(filename, exts):
  46         return getExtension(filename) in exts
  47
  48 ALLOWED_IMAGES = set(["jpeg", "png"])
  49 def isAllowedImage(data):
  50         return imghdr.what(None, data) in ALLOWED_IMAGES
  51
  52 def shouldReturnJson():
  53         return "application/json" in request.accept_mimetypes and \
  54                         not "text/html" in request.accept_mimetypes
  55
  56 def randomString(n):
  57         return ''.join(random.choice(string.ascii_lowercase + \
  58                         string.ascii_uppercase + string.digits) for _ in range(n))
  59
  60 def doFileUpload(file, fileType, fileTypeDesc):
  61         if not file or file is None or file.filename == "":
  62                 flash("No selected file", "danger")
  63                 return None, None
  64
  65         assert os.path.isdir(app.config["UPLOAD_DIR"]), "UPLOAD_DIR must exist"
  66
  67         allowedExtensions = []
  68         isImage = False
  69         if fileType == "image":
  70                 allowedExtensions = ["jpg", "jpeg", "png"]
  71                 isImage = True
  72         elif fileType == "zip":
  73                 allowedExtensions = ["zip"]
  74         else:
  75                 raise Exception("Invalid fileType")
  76
  77         ext = getExtension(file.filename)
  78         if ext is None or not ext in allowedExtensions:
  79                 flash("Please upload " + fileTypeDesc, "danger")
  80                 return None, None
  81
  82         if isImage and not isAllowedImage(file.stream.read()):
  83                 flash("Uploaded image isn't actually an image", "danger")
  84                 return None, None
  85
  86         file.stream.seek(0)
  87
  88         filename = randomString(10) + "." + ext
  89         filepath = os.path.join(app.config["UPLOAD_DIR"], filename)
  90         file.save(filepath)
  91         return "/uploads/" + filename, filepath
  92
  93 def make_flask_user_password(plaintext_str):
  94         # http://passlib.readthedocs.io/en/stable/modular_crypt_format.html
  95         # http://passlib.readthedocs.io/en/stable/lib/passlib.hash.bcrypt.html#format-algorithm
  96         # Flask_User stores passwords in the Modular Crypt Format.
  97         # https://github.com/lingthio/Flask-User/blob/master/flask_user/user_manager__settings.py#L166
  98         #   Note that Flask_User allows customizing password algorithms.
  99         #   USER_PASSLIB_CRYPTCONTEXT_SCHEMES defaults to bcrypt but if
 100         #   default changes or is customized, the code below needs adapting.
 101         # Individual password values will look like:
 102         #   $2b$12$.az4S999Ztvy/wa3UdQvMOpcki1Qn6VYPXmEFMIdWQyYs7ULnH.JW
 103         #   $XX$RR$SSSSSSSSSSSSSSSSSSSSSSHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
 104         # $XX : Selects algorithm (2b is bcrypt).
 105         # $RR : Selects bcrypt key expansion rounds (12 is 2**12 rounds).
 106         # $SSS... : 22 chars of (random, per-password) salt
 107         #  HHH... : 31 remaining chars of password hash (note no dollar sign)
 108         import bcrypt
 109         plaintext = plaintext_str.encode("UTF-8")
 110         password = bcrypt.hashpw(plaintext, bcrypt.gensalt())
 111         if isinstance(password, str):
 112                 return password
 113         else:
 114                 return password.decode("UTF-8")
 115
 116 def loginUser(user):
 117         def _call_or_get(v):
 118                 if callable(v):
 119                         return v()
 120                 else:
 121                         return v
 122
 123         # User must have been authenticated
 124         if not user:
 125                 return False
 126
 127         if user.rank == UserRank.BANNED:
 128                 flash("You have been banned.", "danger")
 129                 return False
 130
 131         user.active = True
 132         if not user.rank.atLeast(UserRank.NEW_MEMBER):
 133                 user.rank = UserRank.MEMBER
 134
 135         db.session.commit()
 136
 137         # Check if user account has been disabled
 138         if not _call_or_get(user.is_active):
 139                 flash("Your account has not been enabled.", "danger")
 140                 return False
 141
 142         # Use Flask-Login to sign in user
 143         login_user(user, remember=True)
 144         signals.user_logged_in.send(current_app._get_current_object(), user=user)
 145
 146         flash("You have signed in successfully.", "success")
 147
 148         return True
 149
 150
 151 def rank_required(rank):
 152         def decorator(f):
 153                 @wraps(f)
 154                 def decorated_function(*args, **kwargs):
 155                         if not current_user.is_authenticated:
 156                                 return redirect(url_for("user.login"))
 157                         if not current_user.rank.atLeast(rank):
 158                                 abort(403)
 159
 160                         return f(*args, **kwargs)
 161
 162                 return decorated_function
 163         return decorator
 164
 165 def getPackageByInfo(author, name):
 166         user = User.query.filter_by(username=author).first()
 167         if user is None:
 168                 abort(404)
 169
 170         package = Package.query.filter_by(name=name, author_id=user.id, soft_deleted=False).first()
 171         if package is None:
 172                 abort(404)
 173
 174         return package
 175
 176 def is_package_page(f):
 177         @wraps(f)
 178         def decorated_function(*args, **kwargs):
 179                 if not ("author" in kwargs and "name" in kwargs):
 180                         abort(400)
 181
 182                 package = getPackageByInfo(kwargs["author"], kwargs["name"])
 183
 184                 del kwargs["author"]
 185                 del kwargs["name"]
 186
 187                 return f(package=package, *args, **kwargs)
 188
 189         return decorated_function
 190
 191
 192 def addNotification(target, causer, title, url, package=None):
 193         try:
 194                 iter(target)
 195                 for x in target:
 196                         addNotification(x, causer, title, url, package)
 197                 return
 198         except TypeError:
 199                 pass
 200
 201         if target.rank.atLeast(UserRank.NEW_MEMBER) and target != causer:
 202                 Notification.query.filter_by(user=target, causer=causer, title=title, url=url, package=package).delete()
 203                 notif = Notification(target, causer, title, url, package)
 204                 db.session.add(notif)
 205
 206
 207 def addAuditLog(severity, causer, title, url, package=None, description=None):
 208         entry = AuditLogEntry(causer, severity, title, url, package, description)
 209         db.session.add(entry)
 210
 211
 212 def clearNotifications(url):
 213         if current_user.is_authenticated:
 214                 Notification.query.filter_by(user=current_user, url=url).delete()
 215                 db.session.commit()
 216
 217
 218 YESES = ["yes", "true", "1", "on"]
 219
 220 def isYes(val):
 221         return val and val.lower() in YESES
 222
 223
 224 def isNo(val):
 225         return val and not isYes(val)
 226
 227 def nonEmptyOrNone(str):
 228         if str is None or str == "":
 229                 return None
 230
 231         return str