diff --git a/swh/core/db/__init__.py b/swh/core/db/__init__.py index 455f56d..2192c7d 100644 --- a/swh/core/db/__init__.py +++ b/swh/core/db/__init__.py @@ -1,193 +1,207 @@ # Copyright (C) 2015-2019 The Software Heritage developers # See the AUTHORS file at the top-level directory of this distribution # License: GNU General Public License version 3, or any later version # See top-level LICENSE file for more information import binascii import datetime import enum import json +import logging import os import threading from contextlib import contextmanager import psycopg2 import psycopg2.extras +logger = logging.getLogger(__name__) + + psycopg2.extras.register_uuid() def escape(data): if data is None: return '' if isinstance(data, bytes): return '\\x%s' % binascii.hexlify(data).decode('ascii') elif isinstance(data, str): return '"%s"' % data.replace('"', '""') elif isinstance(data, datetime.datetime): # We escape twice to make sure the string generated by # isoformat gets escaped return escape(data.isoformat()) elif isinstance(data, dict): return escape(json.dumps(data)) elif isinstance(data, list): return escape("{%s}" % ','.join(escape(d) for d in data)) elif isinstance(data, psycopg2.extras.Range): # We escape twice here too, so that we make sure # everything gets passed to copy properly return escape( '%s%s,%s%s' % ( '[' if data.lower_inc else '(', '-infinity' if data.lower_inf else escape(data.lower), 'infinity' if data.upper_inf else escape(data.upper), ']' if data.upper_inc else ')', ) ) elif isinstance(data, enum.IntEnum): return escape(int(data)) else: # We don't escape here to make sure we pass literals properly return str(data) def typecast_bytea(value, cur): if value is not None: data = psycopg2.BINARY(value, cur) return data.tobytes() class BaseDb: """Base class for swh.*.*Db. cf. swh.storage.db.Db, swh.archiver.db.ArchiverDb """ @classmethod def adapt_conn(cls, conn): """Makes psycopg2 use 'bytes' to decode bytea instead of 'memoryview', for this connection.""" cur = conn.cursor() cur.execute("SELECT null::bytea, null::bytea[]") bytea_oid = cur.description[0][1] bytea_array_oid = cur.description[1][1] t_bytes = psycopg2.extensions.new_type( (bytea_oid,), "bytea", typecast_bytea) psycopg2.extensions.register_type(t_bytes, conn) t_bytes_array = psycopg2.extensions.new_array_type( (bytea_array_oid,), "bytea[]", t_bytes) psycopg2.extensions.register_type(t_bytes_array, conn) @classmethod def connect(cls, *args, **kwargs): """factory method to create a DB proxy Accepts all arguments of psycopg2.connect; only some specific possibilities are reported below. Args: connstring: libpq2 connection string """ conn = psycopg2.connect(*args, **kwargs) return cls(conn) @classmethod def from_pool(cls, pool): conn = pool.getconn() return cls(conn, pool=pool) def __init__(self, conn, pool=None): """create a DB proxy Args: conn: psycopg2 connection to the SWH DB pool: psycopg2 pool of connections """ self.adapt_conn(conn) self.conn = conn self.pool = pool def put_conn(self): if self.pool: self.pool.putconn(self.conn) def cursor(self, cur_arg=None): """get a cursor: from cur_arg if given, or a fresh one otherwise meant to avoid boilerplate if/then/else in methods that proxy stored procedures """ if cur_arg is not None: return cur_arg else: return self.conn.cursor() _cursor = cursor # for bw compat @contextmanager def transaction(self): """context manager to execute within a DB transaction Yields: a psycopg2 cursor """ with self.conn.cursor() as cur: try: yield cur self.conn.commit() except Exception: if not self.conn.closed: self.conn.rollback() raise def copy_to(self, items, tblname, columns, cur=None, item_cb=None, default_values={}): """Copy items' entries to table tblname with columns information. Args: items (List[dict]): dictionaries of data to copy over tblname. tblname (str): destination table's name. columns ([str]): keys to access data in items and also the column names in the destination table. default_values (dict): dictionary of default values to use when inserting entried int the tblname table. cur: a db cursor; if not given, a new cursor will be created. item_cb (fn): optional function to apply to items's entry. """ read_file, write_file = os.pipe() def writer(): cursor = self.cursor(cur) with open(read_file, 'r') as f: cursor.copy_expert('COPY %s (%s) FROM STDIN CSV' % ( tblname, ', '.join(columns)), f) write_thread = threading.Thread(target=writer) write_thread.start() try: with open(write_file, 'w') as f: for d in items: if item_cb is not None: item_cb(d) - line = [escape(d.get(k, default_values.get(k))) - for k in columns] + line = [] + for k in columns: + try: + value = d.get(k, default_values.get(k)) + line.append(escape(value)) + except Exception as e: + logger.error( + 'Could not escape value `%r` for column `%s`:' + 'Received exception: `%s`', + value, k, e + ) + raise e from None f.write(','.join(line)) f.write('\n') finally: # No problem bubbling up exceptions, but we still need to make sure # we finish copying, even though we're probably going to cancel the # transaction. write_thread.join() def mktemp(self, tblname, cur=None): self.cursor(cur).execute('SELECT swh_mktemp(%s)', (tblname,))