Wrapper script that helps convert srf files to fastq files.

It can do the following:
  split the fastq into two files (for paired end reads)
  add in a flowcell id to the header (for either type of read).

diff --git a/scripts/srf2named_fastq.py b/scripts/srf2named_fastq.py
new file mode 100644 (file)
index 0000000..b6b8b55
--- /dev/null
+++ b/scripts/srf2named_fastq.py
@@ -0,0 +1,167 @@
+#!/usr/bin/env python
+from optparse import OptionParser
+import os
+from subprocess import Popen, PIPE
+import sys
+
+from htsworkflow.util.opener import autoopen
+
+
+def main(cmdline=None):
+    parser = make_parser()
+    opts, args = parser.parse_args(cmdline)
+
+    if len(args) != 1:
+        parser.error("Requires one argument")
+
+    if opts.flowcell is not None:
+        header = "%s_" % (opts.flowcell,)
+    else:
+        header = ''
+
+    if opts.single:
+        left = open_write(opts.single, opts.force)
+    else:
+        left = open_write(opts.left, opts.force)
+        right = open_write(opts.right, opts.force)
+    
+    # open the srf, fastq, or compressed fastq
+    if is_srf(args[0]):
+        source = srf_open(args[0], opts.cnf1)
+    else:
+        source = autoopen(args[0])
+
+    if opts.single:
+        convert_single_to_fastq(source, left, header)
+    else:
+        convert_single_to_two_fastq(source, left, right, opts.mid, header)
+   
+    return 0
+
+def make_parser():
+    parser = OptionParser("""%prog: [options] file
+
+file can be either a fastq file or a srf file.
+You can also force the flowcell ID to be added to the header.""")
+    parser.add_option('-c','--cnf1',default=False, action="store_true",
+      help="pass -c to srf2fastq, needed for calibrated quality values"
+    )
+    parser.add_option('--force', default=False, action="store_true",
+                      help="overwrite existing files.")
+    parser.add_option('--flowcell', default=None,
+                      help="add flowcell id header to sequence")
+    parser.add_option('-l','--left', default="r1.fastq",
+                      help='left side filename')
+    parser.add_option('-r','--right', default="r2.fastq",
+                      help='right side filename')
+    parser.add_option('-m','--mid', default=None, 
+                      help='actual sequence mid point')
+    parser.add_option('-s','--single', default=None,
+                      help="single fastq target name")
+    return parser
+
+
+def srf_open(filename, cnf1=False):
+    """
+    Make a stream from srf file using srf2fastq
+    """
+    
+    cmd = ['srf2fastq']
+    if cnf1:
+        cmd.append('-c')
+    cmd.append(filename)
+        
+    p = Popen(cmd, stdout=PIPE)
+    return p.stdout
+    
+
+def convert_single_to_fastq(instream, target1, header=''):
+    for line in instream:
+        # sequence header
+        if line[0] == '@':
+            line = line.strip()
+            target1.write('@')
+            target1.write(header)
+            target1.write(line[1:])
+            target1.write(os.linesep)
+
+        # quality header
+        elif line[0] == '+':
+            target1.write(line)
+        # sequence or quality data
+        else:
+            target1.write(line)
+        
+def convert_single_to_two_fastq(instream, target1, target2, mid=None, header=''):
+    if mid is not None:
+        mid = int(mid)
+
+    for line in instream:
+        # sequence header
+        if line[0] == '@':
+            line = line.strip()
+            target1.write('@')
+            target1.write(header)
+            target1.write(line[1:])
+            target1.write("/1")
+            target1.write(os.linesep)
+
+            target2.write('@')
+            target2.write(header)
+            target2.write(line[1:])
+            target2.write("/1")
+            target2.write(os.linesep)
+
+        # quality header
+        elif line[0] == '+':
+            target1.write(line)
+            target2.write(line)
+        # sequence or quality data
+        else:
+            line = line.strip()
+            if mid is None:
+                mid = len(line)/2
+            target1.write(line[:mid])
+            target1.write(os.linesep)
+            target2.write(line[mid:])
+            target2.write(os.linesep)
+
+def is_srf(filename):
+    """
+    Check filename to see if it is likely to be a SRF file
+    """
+    f = open(filename, 'r')
+    header = f.read(4)
+    f.close()
+    return header == "SSRF"
+
+def open_write(filename, force=False):
+    """
+    Open a file, but throw an exception if it already exists
+    """
+    if not force:
+        if os.path.exists(filename):
+            raise RuntimeError("%s exists" % (filename,))
+
+    return open(filename, 'w')
+
+def foo():
+    path, name = os.path.split(filename)
+    base, ext = os.path.splitext(name)
+
+    target1_name = base + '_r1.fastq'
+    target2_name = base + '_r2.fastq'
+
+    for target_name in [target1_name, target2_name]:
+        print 'target name', target_name
+        if os.path.exists(target_name):
+            raise RuntimeError("%s exists" % (target_name,))
+
+    instream = open(filename,'r')
+    target1 = open(target1_name,'w')
+    target2 = open(target2_name,'w')
+
+
+
+if __name__ == "__main__":
+    sys.exit(main(sys.argv[1:]))

diff --git a/setup.py b/setup.py
index 232017b8fd7f9a3d3c65e11bb19443ed920f3af5..40ee4eb6e1dd42e208c2d0694327262abd162068 100644 (file)
--- a/setup.py
+++ b/setup.py
@@ -32,5 +32,6 @@ setup(
         'scripts/runner',
         'scripts/spoolwatcher', 
         'scripts/srf',
+       'scripts/srf2named_fastq.py'
         ],
 )