src/backend/nopaste.py

   1 #!/usr/bin/python3
   2
   3 import datetime
   4 import magic
   5
   6 from .misc import Object
   7
   8 class Nopaste(Object):
   9         def create(self, content, subject=None, mimetype=None, expires=None, account=None, address=None):
  10                 self._cleanup_database()
  11
  12                 # Store the blob
  13                 blob_id = self._store_blob(content)
  14
  15                 # Guess the mimetype if none set
  16                 if not mimetype:
  17                         mimetype = magic.from_buffer(content, mime=True)
  18
  19                 uid = None
  20                 if account:
  21                         uid = account.uid
  22
  23                 if expires:
  24                         expires = datetime.datetime.utcnow() + datetime.timedelta(seconds=expires)
  25
  26                 # http://blog.00null.net/easily-generating-random-strings-in-postgresql/
  27                 res = self.db.get("""
  28                         INSERT INTO
  29                                 nopaste
  30                         (
  31                                 uuid,
  32                                 subject,
  33                                 content,
  34                                 time_expires,
  35                                 address,
  36                                 uid,
  37                                 mimetype,
  38                                 size,
  39                                 blob_id
  40                         )
  41                         VALUES
  42                         (
  43                                 random_slug(), %s, %s, %s, %s, %s, %s, %s, %s
  44                         )
  45                         RETURNING
  46                                 uuid
  47                         """, subject, content, expires or None, address, uid, mimetype, len(content), blob_id,
  48                 )
  49
  50                 if res:
  51                         return res.uuid
  52
  53         def _store_blob(self, data):
  54                 """
  55                         Stores the blob by sending it to the database and returning its ID
  56                 """
  57                 blob = self.db.get("""
  58                         INSERT INTO
  59                                 nopaste_blobs
  60                         (
  61                                 data
  62                         )
  63                         VALUES
  64                         (
  65                                 %s
  66                         )
  67                         ON CONFLICT
  68                         (
  69                                 data
  70                         )
  71                         DO UPDATE SET
  72                                 last_uploaded_at = CURRENT_TIMESTAMP
  73                         RETURNING
  74                                 id
  75                         """, data
  76                 )
  77
  78                 # Return the ID
  79                 return blob.id
  80
  81         def get(self, uuid):
  82                 res = self.db.get("SELECT uuid, subject, time_created, time_expires, address, uid, \
  83                         mimetype, views, size FROM nopaste WHERE uuid = %s AND (CASE WHEN time_expires \
  84                         IS NULL THEN TRUE ELSE NOW() < time_expires END)", uuid)
  85
  86                 if res:
  87                         # Get the account that uploaded this if available
  88                         res.account = None
  89                         if res.uid:
  90                                 res.account = self.backend.accounts.get_by_uid(res.uid)
  91
  92                         # Touch the entry so it won't be deleted when it is still used
  93                         self._update_lastseen(uuid)
  94
  95                 return res
  96
  97         def get_content(self, uuid):
  98                 res = self.db.get("SELECT content FROM nopaste \
  99                         WHERE uuid = %s", uuid)
 100
 101                 if res:
 102                         return bytes(res.content)
 103
 104         def _update_lastseen(self, uuid):
 105                 self.db.execute("UPDATE nopaste SET time_lastseen = NOW(), views = views + 1 \
 106                         WHERE uuid = %s", uuid)
 107
 108         def _cleanup_database(self):
 109                 # Delete old pastes when they are expired or when they have not been
 110                 # accessed in a long time.
 111                 self.db.execute("DELETE FROM nopaste WHERE (CASE \
 112                         WHEN time_expires IS NULL \
 113                                 THEN time_lastseen + INTERVAL '6 months' <= NOW() \
 114                         ELSE NOW() >= time_expires END)")