restore SortSamTool call, add boolean to skip samtools-based sort if …

…specified (sort by default, but not in the case where align_mem_one_rg does it via Picard

tools/bwa.py

@@ -100,6 +100,8 @@ def align_mem_bam(self, inBam, refDb, outBam, options=None,
                     picardOptions=['SORT_ORDER=coordinate', 'USE_THREADING=true', 'CREATE_INDEX=true'],
                     JVMmemory=JVMmemory
                 )
+                if outBam.endswith(".bam") or outBam.endswith(".cram"):
+                    samtools.index(outBam)
                 for bam in align_bams:
                     os.unlink(bam)
 
@@ -168,20 +170,44 @@ def align_mem_one_rg(self, inBam, refDb, outBam, rgid=None, options=None,
 
         assert len(readgroup_line) > 0
 
-        # rather than reheader the alignment bam file later so it has the readgroup information
-        # from the original bam file, we'll pass the RG line to bwa to write out
-        self.mem(one_rg_inBam, refDb, outBam, options=options+['-R',
-                 readgroup_line.rstrip("\r\n")],
-                 min_score_to_filter=min_score_to_filter, threads=threads, invert_filter=invert_filter)
-
-        # if there was more than one RG in the input, we had to create a temporary file with the one RG specified
-        # and we can safely delete it this file
-        # if there was only one RG in the input, we used it directly and should not delete it
-        if removeInput:
-            os.unlink(one_rg_inBam)
+        with util.file.tempfname('.aligned.bam') as tmp_bam_aligned:
+            # rather than reheader the alignment bam file later so it has the readgroup information
+            # from the original bam file, we'll pass the RG line to bwa to write out
+            self.mem(one_rg_inBam, refDb, tmp_bam_aligned, options=options+['-R',
+                     readgroup_line.rstrip("\r\n")],
+                     min_score_to_filter=min_score_to_filter, threads=threads, invert_filter=invert_filter, sort=False)
+
+            # if there was more than one RG in the input, we had to create a temporary file with the one RG specified
+            # and we can safely delete it this file
+            # if there was only one RG in the input, we used it directly and should not delete it
+            if removeInput:
+                os.unlink(one_rg_inBam)
+
+            # if the aligned bam file contains no reads after filtering
+            # just create an empty file
+            if tools.samtools.SamtoolsTool().count(tmp_bam_aligned) == 0:
+                util.file.touch(outBam)
+            else:
+                # samtools reheader seems to segfault on some alignments created by bwa
+                # so rather than reheader, BWA will write out the RG given to it via '-R'
+                # reheadered_bam = util.file.mkstempfname('.reheadered.bam')
+                # tools.samtools.SamtoolsTool().reheader(tmp_bam_aligned, headerFile, reheadered_bam)
+                # os.unlink(tmp_bam_aligned)
+                # os.unlink(headerFile)
+                # os.system("samtools view -h {} > /Users/tomkinsc/Desktop/test_reheader.bam".format(reheadered_bam))
+
+                # sort
+                sorter = tools.picard.SortSamTool()
+                sorter.execute(
+                    tmp_bam_aligned,
+                    outBam,
+                    sort_order='coordinate',
+                    picardOptions=['CREATE_INDEX=true', 'VALIDATION_STRINGENCY=SILENT'],
+                    JVMmemory=JVMmemory
+                )
 
     def mem(self, inReads, refDb, outAlign, options=None, min_score_to_filter=None,
-            threads=None, invert_filter=False):
+            threads=None, invert_filter=False, sort=True):
         options = [] if not options else options
 
         threads = util.misc.sanitize_thread_count(threads)
@@ -202,11 +228,13 @@ def mem(self, inReads, refDb, outAlign, options=None, min_score_to_filter=None,
             else:
                 aln_sam_filtered = aln_sam
 
-            samtools.sort(aln_sam_filtered, outAlign, threads=threads)
+            if sort:
+                samtools.sort(aln_sam_filtered, outAlign, threads=threads)
 
-        # cannot index sam files; only do so if a bam/cram is desired
-        if outAlign.endswith(".bam") or outAlign.endswith(".cram"):
-            samtools.index(outAlign)
+                # cannot index sam files; only do so if a bam/cram is desired
+                # sorting is required for indexing
+                if outAlign.endswith(".bam") or outAlign.endswith(".cram"):
+                    samtools.index(outAlign)
 
     def filter_sam_on_alignment_score(self, in_sam, out_sam, min_score_to_filter,
                                       bwa_options, invert_filter=False):