#########################################################################
# MacSyFinder - Detection of macromolecular systems in protein dataset #
# using systems modelling and similarity search. #
# Authors: Sophie Abby, Bertrand Neron #
# Copyright (c) 2014-2020 Institut Pasteur (Paris) and CNRS. #
# See the COPYRIGHT file for details #
# #
# This file is part of MacSyFinder package. #
# #
# MacSyFinder is free software: you can redistribute it and/or modify #
# it under the terms of the GNU General Public License as published by #
# the Free Software Foundation, either version 3 of the License, or #
# (at your option) any later version. #
# #
# MacSyFinder is distributed in the hope that it will be useful, #
# but WITHOUT ANY WARRANTY; without even the implied warranty of #
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
# GNU General Public License for more details . #
# #
# You should have received a copy of the GNU General Public License #
# along with MacSyFinder (COPYING). #
# If not, see <https://www.gnu.org/licenses/>. #
#########################################################################
from itertools import groupby
from collections import namedtuple
import os.path
import logging
from macsypy.error import MacsypyError
_log = logging.getLogger(__name__)
[docs]def fasta_iter(fasta_file):
"""
:param fasta_file: the file containing all input sequences in fasta format.
:type fasta_file: file object
:author: http://biostar.stackexchange.com/users/36/brentp
:return: for a given fasta file, it returns an iterator which yields tuples
(string id, string comment, int sequence length)
:rtype: iterator
"""
# ditch the boolean (x[0]) and just keep the header or sequence since
# we know they alternate.
faiter = (x[1] for x in groupby(fasta_file, lambda line: line[0] == ">"))
for header in faiter:
# drop the ">"
header = next(header)[1:].strip()
header = header.split()
_id = header[0]
comment = ' '.join(header[1:])
seq = ''.join(s.strip() for s in next(faiter))
length = len(seq)
yield _id, comment, length
[docs]class Indexes:
"""
Handle the indexes for macsyfinder:
- find the indexes required by macsyfinder to compute some scores, or build them.
"""
[docs] def __init__(self, cfg):
"""
The constructor retrieves the file of indexes in the case they are not present
or the user asked for build indexes (--idx)
Launch the indexes building.
:param cfg: the configuration
:type cfg: :class:`macsypy.config.Config` object
"""
self.cfg = cfg
self._fasta_path = cfg.sequence_db()
self.name = os.path.basename(self._fasta_path)
self._my_indexes = None # path
[docs] def build(self, force=False):
"""
Build the indexes from the sequence data set in fasta format
:param force: If True, force the index building even
if the index files are present in the sequence data set folder
:type force: boolean
"""
my_indexes = self.find_my_indexes()
###########################
# build indexes if needed #
###########################
index_dir = os.path.abspath(os.path.dirname(self.cfg.sequence_db()))
if force or not my_indexes:
# formatdb create indexes in the same directory as the sequence_db
# so it must be writable
# if the directory is not writable, formatdb do a Segmentation fault
if not os.access(index_dir, os.R_OK | os.W_OK):
msg = f"cannot build indexes, ({index_dir}) is not writable"
_log.critical(msg)
raise IOError(msg)
self._build_my_indexes()
self._my_indexes = self.find_my_indexes()
assert self._my_indexes, "failed create macsyfinder indexes"
[docs] def find_my_indexes(self):
"""
:return: the file of macsyfinder indexes if it exists in the dataset folder, None otherwise.
:rtype: string
"""
path = os.path.join(os.path.dirname(self.cfg.sequence_db()), self.name + ".idx")
if os.path.exists(path):
return path
[docs] def _build_my_indexes(self):
"""
Build macsyfinder indexes. These indexes are stored in a file.
The file format is the following:
- one entry per line, with each line having this format:
- sequence id;sequence length;sequence rank
"""
try:
with open(self._fasta_path, 'r') as fasta_file:
with open(os.path.join(os.path.dirname(self.cfg.sequence_db()), self.name + ".idx"), 'w') as my_base:
f_iter = fasta_iter(fasta_file)
seq_nb = 0
for seq_id, comment, length in f_iter:
seq_nb += 1
my_base.write(f"{seq_id};{length:d};{seq_nb:d}\n")
except Exception as err:
msg = f"unable to index the sequence dataset: {self.cfg.sequence_db()} : {err}"
_log.critical(msg, exc_info=True)
raise MacsypyError(msg)
"""handle name, topology type, and min/max positions in the sequence dataset for a replicon and list of genes.
each genes is representing by a tuple (seq_id, length)"""
RepliconInfo = namedtuple('RepliconInfo', 'topology, min, max, genes')
[docs]class RepliconDB:
"""
Stores information (topology, min, max, [genes]) for all replicons in the sequence_db
the Replicon object must be instantiated only for sequence_db of type 'gembase' or 'ordered_replicon'
"""
ordered_replicon_name = 'UserReplicon'
[docs] def __init__(self, cfg):
"""
:param cfg: The configuration object
:type cfg: :class:`macsypy.config.Config` object
.. note ::
This class can be instanciated only if the db_type is 'gembase' or 'ordered_replicon'
"""
self.cfg = cfg
assert self.cfg.db_type() in ('gembase', 'ordered_replicon')
idx = Indexes(self.cfg)
self.sequence_idx = idx.find_my_indexes()
self.topology_file = self.cfg.topology_file()
self._DB = {}
if self.topology_file:
topo_dict = self._fill_topology()
else:
topo_dict = {}
if self.cfg.db_type() == 'gembase':
self._fill_gembase_min_max(topo_dict, default_topology=self.cfg.replicon_topology())
else:
self._fill_ordered_min_max(self.cfg.replicon_topology())
[docs] def _fill_topology(self):
"""
Fill the internal dictionary with min and max positions for each replicon_name of the sequence_db
"""
topo_dict = {}
with open(self.topology_file) as topo_f:
for line in topo_f:
if line.startswith('#'):
continue
replicon_name, topo = line.split(':')
replicon_name = replicon_name.strip()
topo = topo.strip().lower()
topo_dict[replicon_name] = topo
return topo_dict
[docs] def _fill_ordered_min_max(self, default_topology=None):
"""
For the replicon_name of the ordered_replicon sequence base, fill the internal dict with RepliconInfo
:param default_topology: the topology provided by config.replicon_topology
:type default_topology: string
"""
_min = 1
# self.sequence_idx is a file with the following structure seq_id;seq_length;seq_rank\n
with open(self.sequence_idx) as idx_f:
_max = 0
genes = []
for line in idx_f:
seq_id, length, _rank = line.split(";")
genes.append((seq_id, length))
_max += 1
self._DB[self.ordered_replicon_name] = RepliconInfo(default_topology, _min, _max, genes)
[docs] def _fill_gembase_min_max(self, topology, default_topology):
"""
For each replicon_name of a gembase dataset, it fills the internal dictionary with a namedtuple RepliconInfo
:param topology: the topologies for each replicon
(parsed from the file specified with the option --topology-file)
:type topology: dict
:param default_topology: the topology provided by the config.replicon_topology
:type default_topology: string
"""
def grp_replicon(line):
"""
in gembase the identifier of fasta sequence follows the following schema:
<replicon-name>_<seq-name> with eventually '_' inside the <replicon_name>
but not in the <seq-name>.
so grp_replicon allow to group sequences belonging to the same replicon.
"""
return "_".join(line.split('_')[: -1])
def parse_entry(entry):
"""
parse an entry in the index file (.idx)
an entry have the following format sequence_id;sequence length;sequence rank in replicon
"""
entry = entry.rstrip()
seq_id, length, rank = entry.split(';')
replicon_name = "_".join(seq_id.split('_')[: -1])
seq_name = seq_id.split('_')[-1]
return replicon_name, seq_name, length, int(rank)
with open(self.sequence_idx) as idx_f:
replicons = (x[1] for x in groupby(idx_f, grp_replicon))
for replicon in replicons:
genes = []
entry = next(replicon)
replicon_name, seq_name, seq_length, _min = parse_entry(entry)
genes.append((seq_name, seq_length))
for entry in replicon:
# pass all sequence of the replicon until the last one
_, seq_name, seq_length, _ = parse_entry(entry)
genes.append((seq_name, seq_length))
_, seq_name, seq_length, _max = parse_entry(entry)
genes.append((seq_name, seq_length))
if replicon_name in topology:
self._DB[replicon_name] = RepliconInfo(topology[replicon_name], _min, _max, genes)
else:
self._DB[replicon_name] = RepliconInfo(default_topology, _min, _max, genes)
[docs] def __contains__(self, replicon_name):
"""
:param replicon_name: the name of the replicon
:type replicon_name: string
:returns: True if replicon_name is in the repliconDB, false otherwise.
:rtype: boolean
"""
return replicon_name in self._DB
[docs] def __getitem__(self, replicon_name):
"""
:param replicon_name: the name of the replicon to get information on
:type replicon_name: string
:returns: the RepliconInfo for the provided replicon_name
:rtype: :class:`RepliconInfo` object
:raise: KeyError if replicon_name is not in repliconDB
"""
return self._DB[replicon_name]
[docs] def get(self, replicon_name, default=None):
"""
:param replicon_name: the name of the replicon to get informations
:type replicon_name: string
:param default: the value to return if the replicon_name is not in the RepliconDB
:type default: any
:returns: the RepliconInfo for replicon_name if replicon_name is in the repliconDB, else default.
If default is not given, it is set to None, so that this method never raises a KeyError.
:rtype: :class:`RepliconInfo` object
"""
return self._DB.get(replicon_name, default)
[docs] def items(self):
"""
:return: a copy of the RepliconDB as a list of (replicon_name, RepliconInfo) pairs
"""
return list(self._DB.items())
[docs] def iteritems(self):
"""
:return: an iterator over the RepliconDB as a list (replicon_name, RepliconInfo) pairs
"""
return iter(self._DB.items())
[docs] def replicon_names(self):
"""
:return: a copy of the RepliconDB as a list of replicon_names
"""
return list(self._DB.keys())
[docs] def replicon_infos(self):
"""
:return: a copy of the RepliconDB as list of replicons info
:rtype: RepliconInfo instance
"""
return list(self._DB.values())