def __init__(self,
index,
*args,
clean=False,
bwa_opts='-x ont2d',
**kwargs):
"""bwa mem alignment server implementation using python binding.
:param index: bwa index base path, or list thereof.
:param clean: clean-up shared memory on exit.
:param bwa_opts: command line options for bwa mem.
"""
super().__init__(*args, **kwargs)
self.logger = logging.getLogger('BwaServe')
self.index = index
self.bwa_opts = bwa_opts
self.aligner = None
if BwaAligner is None:
raise ImportError(
'{} requires BwaAligner which could not be imported.'.format(
self.__class__.__name__))
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.info('bwa service started.')
def __init__(self):
bam = '/stor/work/Lambowitz/cdw2854/cfNA/tgirt_map/merged_bam/dedup/unfragmented.chrM_filter.bam'
index = '/stor/work/Lambowitz/ref/Ecoli/BL21_DE3.fa'
self.bam = pysam.Samfile(bam)
self.aligner = BwaAligner(index, options='-k 12')
self.matched = re.compile('([0-9]+)M')
self.clipped = re.compile('([0-9]+)S')
self.alignments = None
def align(self, sequence):
"""Align a base sequence.
:param sequence: sequence to align.
:returns: the output of bwa mem call.
"""
if self.aligner is None:
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.debug("Aligning sequence of length {}.".format(
len(sequence)))
return self.aligner.align_seq(sequence)
def __init__(self, reference_path, config, log_filename=None):
self.aligner = BwaAligner(reference_path)
self.log_SNP_insert = np.log(config['SNP_insert'])
self.log_non_SNP_insert = np.log(config['non_SNP_insert'])
self.log_SNP_delete = np.log(config['SNP_delete'])
self.log_non_SNP_delete = np.log(config['non_SNP_delete'])
self.log_SNP_false_good = np.log(config['SNP_false_good'])
self.log_non_SNP_good = np.log(config['non_SNP_good'])
self.log_SNP_true_substitute = np.log(config['SNP_true_substitute'])
self.log_SNP_false_substitute = np.log(config['SNP_false_substitute'])
self.log_non_SNP_substitute = np.log(config['non_SNP_substitute'])
self.log_file = None
if log_filename:
self.log_file = open(log_filename, 'w')
class ecoli_mapper():
def __init__(self):
bam = '/stor/work/Lambowitz/cdw2854/cfNA/tgirt_map/merged_bam/dedup/unfragmented.chrM_filter.bam'
index = '/stor/work/Lambowitz/ref/Ecoli/BL21_DE3.fa'
self.bam = pysam.Samfile(bam)
self.aligner = BwaAligner(index, options='-k 12')
self.matched = re.compile('([0-9]+)M')
self.clipped = re.compile('([0-9]+)S')
self.alignments = None
def ecoli_map(self, chrom, start, end):
aligned = 0.0
self.alignments = []
for aln_count, aln in enumerate(self.bam.fetch(chrom, start, end)):
alns = self.aligner.align_seq(aln.query_sequence)
self.alignments.append(alns)
filtered_alignments = filter(self.filter_bad_cigar, alns)
if list(filtered_alignments):
aligned += 1
return aligned / (aln_count + 1)
def filter_bad_cigar(self, aln):
clipped_base = sum(map(int, self.clipped.findall(aln.cigar))) or 0
mapped_base = sum(map(int, self.matched.findall(aln.cigar)))
return (float(clipped_base) / mapped_base) < 0.2 and aln.NM < 3
def __init__(self,
in_vcf,
reference,
out_vcf="/dev/stdout",
min_length=50,
threshold=0.8,
min_distance=10,
anno_hits=0):
""" The setup """
self.in_vcf = in_vcf
self.reference = reference
self.out_vcf = out_vcf
self.min_length = min_length
self.threshold = threshold
self.min_distance = min_distance
self.anno_hits = anno_hits
self.n_header = None
self.aligner = BwaAligner(self.reference, options="-a")
class BwapyServe(rpc.AttrHandler):
def __init__(self,
index,
*args,
clean=False,
bwa_opts='-x ont2d',
**kwargs):
"""bwa mem alignment server implementation using python binding.
:param index: bwa index base path, or list thereof.
:param clean: clean-up shared memory on exit.
:param bwa_opts: command line options for bwa mem.
"""
super().__init__(*args, **kwargs)
self.logger = logging.getLogger('BwaServe')
self.index = index
self.bwa_opts = bwa_opts
self.aligner = None
if BwaAligner is None:
raise ImportError(
'{} requires BwaAligner which could not be imported.'.format(
self.__class__.__name__))
print(self.bwa_opts)
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.info('bwa service started.')
def _clean_index(self):
self.logger.info('Cleaning alignment proxy.')
self.aligner = None
def __del__(self):
self._clean_index()
@rpc.method
def clean_index(self):
"""Destroy the aligner object, which will cleanup the index in memory."""
self._clean_index()
@rpc.method
@asyncio.coroutine
def align(self, sequence):
"""Align a base sequence.
:param sequence: sequence to align.
:returns: the output of bwa mem call.
"""
if self.aligner is None:
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.debug("Aligning sequence of length {}.".format(
len(sequence)))
results = self.aligner.align_seq(sequence)
self.logger.info("Aligned sequence of {} bases with {} hits.".format(
len(sequence), len(results)))
return results
def __init__(self, bwa_executable, reference, reference_filename, references_dict=None):
self.bwa_executable = bwa_executable
assert reference is not None or references_dict is not None, "one of reference or reference_dict must be not None"
self.reference = reference
self.references_dict = references_dict
self.reference_filename = reference_filename
# A heuristic to check if bwa index has been run already
if not os.path.isfile(self.reference_filename + '.bwt'):
subprocess.run([self.bwa_executable, 'index', self.reference_filename],
stderr=subprocess.PIPE, check=True)
self.bwapy_aligner = None
try:
from bwapy import BwaAligner
options = '-x ont2d'
self.bwapy_aligner = BwaAligner(reference_filename, options=options)
except ImportError:
sys.stderr.write("Could't import bwapy, will use bwa executable to align reads\n")
def __init__(self, index, *args, map_opts={'x': 'ont2d'}, **kwargs):
"""bwa mem alignment server implementation using python binding.
:param index: bwa index base path, or list thereof.
:param map_opts: command line options for bwa mem as dictionary.
"""
super().__init__(*args, **kwargs)
self.logger = logging.getLogger('BwaServe')
self.index = index
# expand map_opts to a string:
opts = []
for k, v in map_opts.items():
opts.append('-{} {}'.format(k, v))
self.bwa_opts = ' '.join(opts)
self.aligner = None
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.info('bwa service started.')
class BwapyServe(rpc.AttrHandler):
def __init__(self, index, *args, clean=False, bwa_opts='-x ont2d', **kwargs):
"""bwa mem alignment server implementation using python binding.
:param index: bwa index base path, or list thereof.
:param clean: clean-up shared memory on exit.
:param bwa_opts: command line options for bwa mem.
"""
super().__init__(*args, **kwargs)
self.logger = logging.getLogger('BwaServe')
self.index = index
self.bwa_opts = bwa_opts
self.aligner = None
if BwaAligner is None:
raise ImportError(
'{} requires BwaAligner which could not be imported.'.format(
self.__class__.__name__
))
print(self.bwa_opts)
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.info('bwa service started.')
def _clean_index(self):
self.logger.info('Cleaning alignment proxy.')
self.aligner = None
def __del__(self):
self._clean_index()
@rpc.method
def clean_index(self):
"""Destroy the aligner object, which will cleanup the index in memory."""
self._clean_index()
@rpc.method
@asyncio.coroutine
def align(self, sequence):
"""Align a base sequence.
:param sequence: sequence to align.
:returns: the output of bwa mem call.
"""
if self.aligner is None:
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.debug("Aligning sequence of length {}.".format(len(sequence)))
results = self.aligner.align_seq(sequence)
self.logger.info("Aligned sequence of {} bases with {} hits.".format(
len(sequence), len(results)
))
return results
def __init__(self, bwa_executable, reference, reference_filename):
self.bwa_executable = bwa_executable
self.reference = reference
self.reference_filename = reference_filename
# A heuristic to check if bwa index has been run already
if not os.path.isfile(self.reference_filename + '.bwt'):
subprocess.run(
[self.bwa_executable, 'index', self.reference_filename],
stderr=subprocess.PIPE,
check=True)
self.bwapy_aligner = None
try:
from bwapy import BwaAligner
self.bwapy_aligner = BwaAligner(reference_filename)
except ImportError:
sys.stderr.write(
"Could't import bwapy, will use bwa executable to align reads\n"
)
class BwapyServe(rpc.AttrHandler):
def __init__(self, index, *args, map_opts={'x': 'ont2d'}, **kwargs):
"""bwa mem alignment server implementation using python binding.
:param index: bwa index base path, or list thereof.
:param map_opts: command line options for bwa mem as dictionary.
"""
super().__init__(*args, **kwargs)
self.logger = logging.getLogger('BwaServe')
self.index = index
# expand map_opts to a string:
opts = []
for k, v in map_opts.items():
opts.append('-{} {}'.format(k, v))
self.bwa_opts = ' '.join(opts)
self.aligner = None
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.info('bwa service started.')
def _clean_index(self):
self.logger.info('Cleaning alignment proxy.')
self.aligner = None
def __del__(self):
self._clean_index()
@rpc.method
def clean_index(self):
"""Destroy the aligner object, which will cleanup the index in memory."""
self._clean_index()
@rpc.method
@asyncio.coroutine
def align(self, sequence):
"""Align a base sequence.
:param sequence: sequence to align.
:returns: the output of bwa mem call.
"""
if self.aligner is None:
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.debug("Aligning sequence of length {}.".format(
len(sequence)))
results = self.aligner.align_seq(sequence)
self.logger.info("Aligned sequence of {} bases with {} hits.".format(
len(sequence), len(results)))
return results
def align(self, sequence):
"""Align a base sequence.
:param sequence: sequence to align.
:returns: the output of bwa mem call.
"""
if self.aligner is None:
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.debug("Aligning sequence of length {}.".format(len(sequence)))
results = self.aligner.align_seq(sequence)
self.logger.info("Aligned sequence of {} bases with {} hits.".format(
len(sequence), len(results)
))
return results
def grm_main(cmdargs):
"""
Builds a graph-genome from the vcf and reference,
creates the sets of kmers at edges in the graph
maps those kmers globally to the reference
reports mapping metrics
Todo:
- document the bwa package and how to install
- better column names along with documentation
"""
if not HASBWALIB:
logging.error("bwapy isn't available on this machine")
sys.exit(1)
args = parse_args(cmdargs)
if not args.regions:
m_ranges = truvari.ref_ranges(args.reference)
else:
m_ranges = truvari.bed_ranges(args.regions)
grm_shared.aligner = BwaAligner(args.reference, '-a')
header = ["key"]
for prefix in ["rup_", "rdn_", "aup_", "adn_"]:
for key in [
"nhits", "avg_q", "avg_ed", "avg_mat", "avg_mis", "dir_hits",
"com_hits", "max_q", "max_ed", "max_mat", "max_mis",
"max_strand", "min_q", "min_ed", "min_mat", "min_mis",
"min_strand"
]:
header.append(prefix + key)
grm_shared.header = header
grm_shared.ref_filename = args.reference
grm_shared.kmersize = args.kmersize
grm_shared.input = args.input
grm_shared.min_size = args.min_size
with multiprocessing.Pool(args.threads, maxtasksperchild=1) as pool:
logging.info("Processing")
chunks = pool.imap(process_entries, m_ranges)
pool.close()
data = pd.concat(chunks, ignore_index=True)
logging.info("Saving; df shape %s", data.shape)
joblib.dump(data, args.output)
logging.info("Finished grm")
pool.join()
def recover_ccs_reads(short_reads, ref_fasta, ss_index, gtf_index,
intron_index, is_canonical, out_dir, prefix, threads):
from bwapy import BwaAligner
# Second scanning of short reads
genome = Fasta(ref_fasta)
options = '-x ont2d -T 19'
bwa_aligner = Aligner(BwaAligner(ref_fasta, options=options))
chunk_size = 250
jobs = []
pool = Pool(threads, env.initializer,
(bwa_aligner, genome.contig_len, genome, gtf_index,
intron_index, ss_index))
for reads in grouper(short_reads, chunk_size):
chunk = [i for i in reads if i is not None]
jobs.append(pool.apply_async(recover_ccs_chunk, (chunk, is_canonical)))
pool.close()
prog = ProgressBar()
prog.update(0)
finished_cnt = 0
reads_count = defaultdict(int)
with open('{}/{}.cand_circ.fa'.format(out_dir, prefix), 'a') as out:
for job in jobs:
finished_cnt += 1
tmp_cnt, ret = job.get()
for key, value in tmp_cnt.items():
reads_count[key] += value
for read_id, circ_id, strand, cir_exon_tag, ss_id, clip_info, segments, circ_seq in ret:
out.write('>{}\t{}\t{}\t{}\t{}\t{}\t{}\n{}\n'.format(
read_id, circ_id, strand, cir_exon_tag, ss_id, clip_info,
segments, circ_seq))
prog.update(100 * finished_cnt / len(jobs))
pool.join()
prog.update(100)
return reads_count
class exogenous_mapper():
def __init__(self, index, nm = 0.1):
self.matched = re.compile('([0-9]+)M')
self.clipped = re.compile('([0-9]+)S')
self.aligner = BwaAligner(index, options = '-k 12 -B 3')
self.NM = nm
self.aligned=None
def map(self, seq):
self.aligned=None
self.aligned = self.aligner.align_seq(seq)
self.aligned = list(filter(self.filter_bad_cigar, self.aligned))
return 1 if self.aligned else 0
def filter_bad_cigar(self, aln):
cigar = aln.cigar
clipped_base = sum(map(int, self.clipped.findall(cigar))) or 0
mapped_base = sum(map(int, self.matched.findall(cigar)))
return ( (float(clipped_base) + aln.NM)/mapped_base ) <= self.NM
class chrM_mapper():
def __init__(self, bam, index):
self.bam = pysam.Samfile(bam)
self.aligner = BwaAligner(index, options='-k 12')
def __align__(self, seq):
alignments = self.aligner.align_seq(seq)
return 1 if alignments else 0
def run_peak(self, chrom, start, end, peak_strand):
alns = 0
chrM_alns = 0
for aln in self.bam.fetch(chrom, start, end):
if aln.is_read1:
aln_strand = '-' if aln.is_reverse else '+'
if aln_strand == peak_strand:
alns += 1
seq = aln.get_forward_sequence()
chrM_alns += self.__align__(seq)
return alns, chrM_alns
def __init__(self, index, *args, clean=False, bwa_opts='-x ont2d', **kwargs):
"""bwa mem alignment server implementation using python binding.
:param index: bwa index base path, or list thereof.
:param clean: clean-up shared memory on exit.
:param bwa_opts: command line options for bwa mem.
"""
super().__init__(*args, **kwargs)
self.logger = logging.getLogger('BwaServe')
self.index = index
self.bwa_opts = bwa_opts
self.aligner = None
if BwaAligner is None:
raise ImportError(
'{} requires BwaAligner which could not be imported.'.format(
self.__class__.__name__
))
print(self.bwa_opts)
self.aligner = BwaAligner(self.index, options=self.bwa_opts)
self.logger.info('bwa service started.')
# server.py
# from flask import Flask, render_template
# app = Flask(__name__, static_folder="../static/dist", template_folder="../static")
# @app.route("/")
# def index():
# return render_template("index.html")
# @app.route("/hello")
# def hello():
# return "Hello World!”
# if __name__ == "__main__":
# app.run()
import pysam
from bwapy import BwaAligner
index = 'path/to/index' # the path given to bwa index
seq = 'ACGATCGCGATCGA'
aligner = BwaAligner(index)
alignments = aligner.align_seq(seq)
print('Found {} alignments.'.format(len(alignments))
for aln in alignments:
print(' ', aln)
class Remap():
""" Class for remapping annotation """
def __init__(self,
in_vcf,
reference,
out_vcf="/dev/stdout",
min_length=50,
threshold=0.8,
min_distance=10,
anno_hits=0):
""" The setup """
self.in_vcf = in_vcf
self.reference = reference
self.out_vcf = out_vcf
self.min_length = min_length
self.threshold = threshold
self.min_distance = min_distance
self.anno_hits = anno_hits
self.n_header = None
self.aligner = BwaAligner(self.reference, options="-a")
def edit_header(self, header=None):
"""
Edits and holds on to the header
"""
if header is None:
with pysam.VariantFile(self.in_vcf, 'r') as fh:
header = fh.header.copy()
header.add_line(('##INFO=<ID=REMAP,Number=1,Type=String,'
'Description="Annotation of alt-seq remapping">'))
if self.anno_hits:
header.add_line(('##INFO=<ID=REMAPHits,Number=.,Type=String,'
'Description="List of chr:start-end of hits">'))
self.n_header = header
def get_end(self, pos, cigar): # pylint: disable=no-self-use
"""
Expand a cigar to get the end position and how many bases are clipped
"""
soft_bases = 0
for i in cigmatch.findall(cigar):
if i[-1] == "S":
soft_bases += int(i[:-1])
elif i[-1] in ["M", "D"]:
pos += int(i[:-1])
return pos, soft_bases
def remap_entry(self, entry, threshold=.8):
"""
Map a sequence and return the information from it
"""
is_del = truvari.entry_variant_type(entry) == "DEL"
if is_del:
seq = str(entry.ref)
else:
seq = entry.alts[0]
all_hits = []
num_hits = 0
partial_hits = 0
close_dist = None
for aln in self.aligner.align_seq(seq):
# Take out the 'same spot' alignment for deletions
dist = abs(aln.pos - entry.pos)
if is_del and aln.rname == entry.chrom and dist < self.min_distance:
continue
# Filter hits below threshold
end, soft = self.get_end(aln.pos, aln.cigar)
seq_len = len(seq)
pct_query = (seq_len - soft) / seq_len
if pct_query < threshold:
partial_hits += 1
continue
hit = f"{aln.rname}:{aln.pos}-{end}.{int(pct_query*100)}"
bisect.insort(all_hits, (pct_query, hit))
num_hits += 1
if aln.rname != entry.chrom:
continue
if close_dist is None or dist < close_dist:
close_dist = dist
if num_hits == 0 and partial_hits == 0:
return "novel", all_hits
if close_dist and close_dist <= len(seq):
return "tandem", all_hits
if num_hits == 0 and partial_hits != 0:
return "partial", all_hits
return "interspersed", all_hits
def annotate_entry(self, entry):
"""
Annotates entries in the vcf and writes to new vcf
"""
if truvari.entry_size(entry) >= self.min_length:
entry.translate(self.n_header)
remap, hits = self.remap_entry(entry)
entry.info["REMAP"] = remap
if self.anno_hits and hits:
entry.info["REMAPHits"] = [
_[1] for _ in hits[-self.anno_hits:]
]
return entry
def annotate_vcf(self):
"""
Annotates the vcf and writes to new vcf
"""
with pysam.VariantFile(self.in_vcf) as fh:
self.edit_header(fh.header.copy())
out = pysam.VariantFile(self.out_vcf, 'w', header=self.n_header)
for entry in fh:
entry = self.annotate_entry(entry)
out.write(entry)
class basecall_model(model):
def __init__(self, reference_path, config, log_filename=None):
self.aligner = BwaAligner(reference_path)
self.log_SNP_insert = np.log(config['SNP_insert'])
self.log_non_SNP_insert = np.log(config['non_SNP_insert'])
self.log_SNP_delete = np.log(config['SNP_delete'])
self.log_non_SNP_delete = np.log(config['non_SNP_delete'])
self.log_SNP_false_good = np.log(config['SNP_false_good'])
self.log_non_SNP_good = np.log(config['non_SNP_good'])
self.log_SNP_true_substitute = np.log(config['SNP_true_substitute'])
self.log_SNP_false_substitute = np.log(config['SNP_false_substitute'])
self.log_non_SNP_substitute = np.log(config['non_SNP_substitute'])
self.log_file = None
if log_filename:
self.log_file = open(log_filename, 'w')
def update_probabilities_internal(self, reference, read,
interesting_bases):
alignments = self.aligner.align_seq("".join(read.basecall))
if len(alignments) == 0:
return
alignment = alignments[0]
cigar = parse_cigar(alignment.cigar)
aligned_reference_length = aligned_length(cigar)
reference_aligned = []
corresponding_read_index = [None for i in reference]
read_aligned = []
reference_index = alignment.pos if read.strand == '+' else len(
reference) - alignment.pos - aligned_reference_length
if read.strand == '-':
if alignment.orient != '-':
print("read and aligner don't agree on its orientation")
return
cigar = list(reversed(cigar))
read_index = 0
UNALIGNED, GOOD, SUBSTITUTION, DELETION, NEAR_INSERTION = 'U', 'G', 'S', 'D', 'I'
reference_status = [UNALIGNED for i in reference[:reference_index]]
insertions = []
for op in cigar:
if op[1] == 'S':
read_index += op[0]
elif op[1] == 'M':
reference_aligned += reference[
reference_index:reference_index + op[0]]
for i in range(op[0]):
corresponding_read_index[reference_index +
i] = read_index + i
if reference[reference_index +
i] == read.basecall[read_index + i]:
reference_status.append(GOOD)
else:
reference_status.append(SUBSTITUTION)
reference_index += op[0]
read_aligned += read.basecall[read_index:read_index + op[0]]
read_index += op[0]
elif op[1] == 'D':
reference_aligned += reference[
reference_index:reference_index + op[0]]
reference_status += [DELETION for i in range(op[0])]
reference_index += op[0]
read_aligned += ['-' for i in range(op[0])]
elif op[1] == 'I':
read_aligned += read.basecall[read_index:read_index + op[0]]
read_index += op[0]
reference_aligned += ['-' for i in range(op[0])]
insertions.append(reference_index)
else:
raise ValueError("Unknown operation: {}".format(op[1]))
reference_status += [UNALIGNED for i in reference[reference_index:]]
for idx in insertions:
if idx > 0 and reference_status[idx - 1] == GOOD:
reference_status[idx - 1] = NEAR_INSERTION
if idx < len(reference) and reference_status[idx] == GOOD:
reference_status[idx] = NEAR_INSERTION
for b in interesting_bases:
if reference_status[b.id] == UNALIGNED:
pass
elif reference_status[b.id] == SUBSTITUTION:
for i, c in enumerate(alphabet):
if c == reference[b.id]:
b.log_probability[i] += self.log_non_SNP_substitute
elif c == read.basecall[corresponding_read_index[b.id]]:
b.log_probability[i] += self.log_SNP_true_substitute
else:
b.log_probability[i] += self.log_SNP_false_substitute
else:
if_SNP, if_non_SNP = None, None
if reference_status[b.id] == GOOD:
if_SNP = self.log_SNP_false_good
if_non_SNP = self.log_non_SNP_good
elif reference_status[b.id] == NEAR_INSERTION:
if_SNP = self.log_SNP_insert
if_non_SNP = self.log_non_SNP_insert
elif reference_status[b.id] == DELETION:
if_SNP = self.log_SNP_delete
if_non_SNP = self.log_non_SNP_delete
for i, c in enumerate(alphabet):
if c == reference[b.id]:
b.log_probability[i] += if_non_SNP
else:
b.log_probability[i] += if_SNP
if self.log_file and reference_status[
b.id] != UNALIGNED and read.strand == '+':
self.log_file.write('{} {}'.format(b.id,
reference_status[b.id]))
if reference_status[b.id] == GOOD or reference_status[
b.id] == SUBSTITUTION:
self.log_file.write(' {}\n'.format(
read.basecall[corresponding_read_index[b.id]]))
else:
self.log_file.write('\n')
class ApproximateAligner:
def __init__(self, bwa_executable, reference, reference_filename):
self.bwa_executable = bwa_executable
self.reference = reference
self.reference_filename = reference_filename
# A heuristic to check if bwa index has been run already
if not os.path.isfile(self.reference_filename + '.bwt'):
subprocess.run(
[self.bwa_executable, 'index', self.reference_filename],
stderr=subprocess.PIPE,
check=True)
self.bwapy_aligner = None
try:
from bwapy import BwaAligner
self.bwapy_aligner = BwaAligner(reference_filename)
except ImportError:
sys.stderr.write(
"Could't import bwapy, will use bwa executable to align reads\n"
)
@staticmethod
def _parse_cigar(cigar):
num = 0
result = []
for character in cigar:
if character >= '0' and character <= '9':
num *= 10
num += ord(character) - ord('0')
else:
result.append((num, character))
num = 0
return result
@staticmethod
def convert_mapping(base_mapping, read):
result = []
for index_in_read, index_in_reference in base_mapping:
if index_in_read in read.sequence_to_signal_mapping:
result.append((read.sequence_to_signal_mapping[index_in_read],
index_in_reference))
return numpy.array(result, dtype=numpy.int)
def _get_base_alignment(self, read):
if self.bwapy_aligner:
alignments = self.bwapy_aligner.align_seq(''.join(read.sequence))
if len(alignments) == 0:
return None
alignment = alignments[0]
cigar = alignment.cigar
is_reverse_complement = alignment.orient == '-'
mapped_position = alignment.pos
else:
read_fastq_filename = None
with tempfile.NamedTemporaryFile(mode='w',
delete=False,
prefix='nadavca_tmp',
suffix='.fastq') as file:
read_fastq_filename = file.name
file.write(read.fastq)
bwa_output_filename = None
with tempfile.NamedTemporaryFile(delete=True,
prefix='nadavca_tmp',
suffix='.sam') as file:
bwa_output_filename = file.name
subprocess.run([
self.bwa_executable, 'mem', self.reference_filename,
read_fastq_filename, '-o', bwa_output_filename
],
stderr=subprocess.PIPE,
check=True)
with simplesam.Reader(open(bwa_output_filename, 'r')) as reader:
sam = reader.next()
if not sam.mapped:
return None
cigar = sam.cigar
is_reverse_complement = sam.reverse
mapped_position = sam.pos - 1
os.remove(read_fastq_filename)
os.remove(bwa_output_filename)
oriented_read = Genome.reverse_complement(
read.sequence) if is_reverse_complement else read.sequence
index_in_read = 0
index_in_reference = mapped_position
base_mapping = []
parsed_cigar = self._parse_cigar(cigar)
for num, operation in parsed_cigar:
if operation == 'S':
index_in_read += num
elif operation == 'M':
for i in range(num):
if self.reference[index_in_reference] == oriented_read[
index_in_read]:
base_mapping.append(
(index_in_read, index_in_reference))
index_in_read += 1
index_in_reference += 1
elif operation == 'D':
index_in_reference += num
elif operation == 'I':
index_in_read += num
else:
raise ValueError(
'Unknown cigar operation: {}'.format(operation))
if is_reverse_complement:
for i, val in enumerate(base_mapping):
base_mapping[i] = (len(read.sequence) - 1 - val[0],
len(self.reference) - 1 - val[1])
base_mapping.reverse()
return numpy.array(base_mapping,
dtype=numpy.int), is_reverse_complement
def get_signal_alignment(self, read, bandwidth):
base_alignment = self._get_base_alignment(read)
if base_alignment is None:
return None
base_mapping, is_reverse_complement = base_alignment
signal_mapping = self.convert_mapping(base_mapping, read)
start_in_reference = signal_mapping[0][1]
end_in_reference = signal_mapping[-1][1] + 1
signal_mapping[:, 1] -= start_in_reference
if is_reverse_complement:
start_in_reference, end_in_reference = \
len(self.reference) - end_in_reference, \
len(self.reference) - start_in_reference
reference_range = (start_in_reference, end_in_reference)
start_in_signal = signal_mapping[0][0]
end_in_signal = signal_mapping[-1][0] + 1
extended_start_in_signal = max(0, start_in_signal - bandwidth)
extended_end_in_signal = min(len(read.normalized_signal),
end_in_signal + bandwidth)
signal_range = (extended_start_in_signal, extended_end_in_signal)
signal_mapping[:, 0] -= extended_start_in_signal
start_in_read_sequence = base_mapping[0][0]
end_in_read_sequence = base_mapping[-1][0] + 1
read_sequence_range = (start_in_read_sequence, end_in_read_sequence)
return ApproximateSignalAlignment(
alignment=signal_mapping,
signal_range=signal_range,
reference_range=reference_range,
read_sequence_range=read_sequence_range,
reverse_complement=is_reverse_complement)
def __init__(self, index, nm = 0.1):
self.matched = re.compile('([0-9]+)M')
self.clipped = re.compile('([0-9]+)S')
self.aligner = BwaAligner(index, options = '-k 12 -B 3')
self.NM = nm
self.aligned=None
def __init__(self, bam, index):
self.bam = pysam.Samfile(bam)
self.aligner = BwaAligner(index, options='-k 12')
def load_index():
global aligner
print('Loading Index: ' + index)
aligner = BwaAligner(index)
print('Index Loaded')