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 # These are given to Jinja in template_filters.py
  27
  28 def abs_url_for(path, **kwargs):
  29         scheme = "https" if app.config["BASE_URL"][:5] == "https" else "http"
  30         return url_for(path, _external=True, _scheme=scheme, **kwargs)
  31
  32 def abs_url(path):
  33         return urljoin(app.config["BASE_URL"], path)
  34
  35 def url_set_query(**kwargs):
  36         args = dict(request.args)
  37         args.update(kwargs)
  38         return url_for(request.endpoint, **args)
  39
  40 def get_int_or_abort(v, default=None):
  41         if v is None:
  42                 return default
  43
  44         try:
  45                 return int(v or default)
  46         except ValueError:
  47                 abort(400)
  48
  49 def getExtension(filename):
  50         return filename.rsplit(".", 1)[1].lower() if "." in filename else None
  51
  52 def isFilenameAllowed(filename, exts):
  53         return getExtension(filename) in exts
  54
  55 ALLOWED_IMAGES = set(["jpeg", "png"])
  56 def isAllowedImage(data):
  57         return imghdr.what(None, data) in ALLOWED_IMAGES
  58
  59 def shouldReturnJson():
  60         return "application/json" in request.accept_mimetypes and \
  61                         not "text/html" in request.accept_mimetypes
  62
  63 def randomString(n):
  64         return ''.join(random.choice(string.ascii_lowercase + \
  65                         string.ascii_uppercase + string.digits) for _ in range(n))
  66
  67 def doFileUpload(file, fileType, fileTypeDesc):
  68         if not file or file is None or file.filename == "":
  69                 flash("No selected file", "danger")
  70                 return None, None
  71
  72         assert os.path.isdir(app.config["UPLOAD_DIR"]), "UPLOAD_DIR must exist"
  73
  74         allowedExtensions = []
  75         isImage = False
  76         if fileType == "image":
  77                 allowedExtensions = ["jpg", "jpeg", "png"]
  78                 isImage = True
  79         elif fileType == "zip":
  80                 allowedExtensions = ["zip"]
  81         else:
  82                 raise Exception("Invalid fileType")
  83
  84         ext = getExtension(file.filename)
  85         if ext is None or not ext in allowedExtensions:
  86                 flash("Please upload " + fileTypeDesc, "danger")
  87                 return None, None
  88
  89         if isImage and not isAllowedImage(file.stream.read()):
  90                 flash("Uploaded image isn't actually an image", "danger")
  91                 return None, None
  92
  93         file.stream.seek(0)
  94
  95         filename = randomString(10) + "." + ext
  96         filepath = os.path.join(app.config["UPLOAD_DIR"], filename)
  97         file.save(filepath)
  98         return "/uploads/" + filename, filepath
  99
 100 def make_flask_user_password(plaintext_str):
 101         # http://passlib.readthedocs.io/en/stable/modular_crypt_format.html
 102         # http://passlib.readthedocs.io/en/stable/lib/passlib.hash.bcrypt.html#format-algorithm
 103         # Flask_User stores passwords in the Modular Crypt Format.
 104         # https://github.com/lingthio/Flask-User/blob/master/flask_user/user_manager__settings.py#L166
 105         #   Note that Flask_User allows customizing password algorithms.
 106         #   USER_PASSLIB_CRYPTCONTEXT_SCHEMES defaults to bcrypt but if
 107         #   default changes or is customized, the code below needs adapting.
 108         # Individual password values will look like:
 109         #   $2b$12$.az4S999Ztvy/wa3UdQvMOpcki1Qn6VYPXmEFMIdWQyYs7ULnH.JW
 110         #   $XX$RR$SSSSSSSSSSSSSSSSSSSSSSHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
 111         # $XX : Selects algorithm (2b is bcrypt).
 112         # $RR : Selects bcrypt key expansion rounds (12 is 2**12 rounds).
 113         # $SSS... : 22 chars of (random, per-password) salt
 114         #  HHH... : 31 remaining chars of password hash (note no dollar sign)
 115         import bcrypt
 116         plaintext = plaintext_str.encode("UTF-8")
 117         password = bcrypt.hashpw(plaintext, bcrypt.gensalt())
 118         if isinstance(password, str):
 119                 return password
 120         else:
 121                 return password.decode("UTF-8")
 122
 123 def loginUser(user):
 124         def _call_or_get(v):
 125                 if callable(v):
 126                         return v()
 127                 else:
 128                         return v
 129
 130         # User must have been authenticated
 131         if not user:
 132                 return False
 133
 134         if user.rank == UserRank.BANNED:
 135                 flash("You have been banned.", "danger")
 136                 return False
 137
 138         user.active = True
 139         if not user.rank.atLeast(UserRank.NEW_MEMBER):
 140                 user.rank = UserRank.MEMBER
 141
 142         db.session.commit()
 143
 144         # Check if user account has been disabled
 145         if not _call_or_get(user.is_active):
 146                 flash("Your account has not been enabled.", "danger")
 147                 return False
 148
 149         # Use Flask-Login to sign in user
 150         login_user(user, remember=True)
 151         signals.user_logged_in.send(current_app._get_current_object(), user=user)
 152
 153         flash("You have signed in successfully.", "success")
 154
 155         return True
 156
 157
 158 def rank_required(rank):
 159         def decorator(f):
 160                 @wraps(f)
 161                 def decorated_function(*args, **kwargs):
 162                         if not current_user.is_authenticated:
 163                                 return redirect(url_for("user.login"))
 164                         if not current_user.rank.atLeast(rank):
 165                                 abort(403)
 166
 167                         return f(*args, **kwargs)
 168
 169                 return decorated_function
 170         return decorator
 171
 172 def getPackageByInfo(author, name):
 173         user = User.query.filter_by(username=author).first()
 174         if user is None:
 175                 abort(404)
 176
 177         package = Package.query.filter_by(name=name, author_id=user.id, soft_deleted=False).first()
 178         if package is None:
 179                 abort(404)
 180
 181         return package
 182
 183 def is_package_page(f):
 184         @wraps(f)
 185         def decorated_function(*args, **kwargs):
 186                 if not ("author" in kwargs and "name" in kwargs):
 187                         abort(400)
 188
 189                 package = getPackageByInfo(kwargs["author"], kwargs["name"])
 190
 191                 del kwargs["author"]
 192                 del kwargs["name"]
 193
 194                 return f(package=package, *args, **kwargs)
 195
 196         return decorated_function
 197
 198
 199 def addNotification(target, causer, title, url, package=None):
 200         try:
 201                 iter(target)
 202                 for x in target:
 203                         addNotification(x, causer, title, url, package)
 204                 return
 205         except TypeError:
 206                 pass
 207
 208         if target.rank.atLeast(UserRank.NEW_MEMBER) and target != causer:
 209                 Notification.query.filter_by(user=target, causer=causer, title=title, url=url, package=package).delete()
 210                 notif = Notification(target, causer, title, url, package)
 211                 db.session.add(notif)
 212
 213
 214 def addAuditLog(severity, causer, title, url, package=None, description=None):
 215         entry = AuditLogEntry(causer, severity, title, url, package, description)
 216         db.session.add(entry)
 217
 218
 219 def clearNotifications(url):
 220         if current_user.is_authenticated:
 221                 Notification.query.filter_by(user=current_user, url=url).delete()
 222                 db.session.commit()
 223
 224
 225 YESES = ["yes", "true", "1", "on"]
 226
 227 def isYes(val):
 228         return val and val.lower() in YESES
 229
 230
 231 def isNo(val):
 232         return val and not isYes(val)
 233
 234 def nonEmptyOrNone(str):
 235         if str is None or str == "":
 236                 return None
 237
 238         return str