diff --git a/pytest.ini b/pytest.ini
new file mode 100644
index 0000000000000000000000000000000000000000..c8d98f29942ac24e83b741a0e102714b44230eab
--- /dev/null
+++ b/pytest.ini
@@ -0,0 +1,2 @@
+[pytest]
+python_paths = workflow/scripts
diff --git a/workflow/scripts/__init__.py b/workflow/scripts/__init__.py
deleted file mode 100644
index 8b137891791fe96927ad78e64b0aad7bded08bdc..0000000000000000000000000000000000000000
--- a/workflow/scripts/__init__.py
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/workflow/scripts/check_design.py b/workflow/scripts/check_design.py
new file mode 100644
index 0000000000000000000000000000000000000000..beb59b25ffa2e7f4d9f7f3f66cbaf0eee464d3c5
--- /dev/null
+++ b/workflow/scripts/check_design.py
@@ -0,0 +1,134 @@
+#!/usr/bin/env python3
+
+'''Check if design file is correctly formatted and matches files list.'''
+
+import argparse
+import logging
+import pandas as pd
+
+EPILOG = '''
+For more details:
+ %(prog)s --help
+'''
+
+## SETTINGS
+
+logger = logging.getLogger(__name__)
+logger.addHandler(logging.NullHandler())
+logger.propagate = False
+logger.setLevel(logging.INFO)
+
+
+def get_args():
+ '''Define arguments.'''
+ parser = argparse.ArgumentParser(
+ description=__doc__, epilog=EPILOG,
+ formatter_class=argparse.RawDescriptionHelpFormatter)
+
+ parser.add_argument('-d', '--design',
+ help="The design file to run QC (TSV format).",
+ required=True)
+
+ parser.add_argument('-f', '--fastq',
+ help="File with list of fastq files (csv format).",
+ required=True)
+
+ parser.add_argument('-p', '--paired',
+ help="True/False if paired-end or single end.",
+ default=True,
+ action='store_true')
+
+ args = parser.parse_args()
+ return args
+
+
+def check_design_headers(design, paired):
+ '''Check if design file conforms to sequencing type.'''
+
+ # Default headers
+ design_template = [
+ 'sample_id',
+ 'biosample',
+ 'factor',
+ 'treatment',
+ 'replicate',
+ 'control_id',
+ 'fastq_read1']
+
+ design_headers = list(design.columns.values)
+
+ if paired: # paired-end data
+ design_template.extend(['fastq_read2'])
+
+ # Check if headers
+ logger.info("Running header check.")
+
+ missing_headers = set(design_template) - set(design_headers)
+
+ if len(missing_headers) > 0:
+ logger.error('Missing column headers: %s', list(missing_headers))
+ raise Exception("Missing column headers: %s" % list(missing_headers))
+
+
+def check_controls(design):
+ '''Check if design file has the correct control mapping.'''
+
+ logger.info("Running control check.")
+
+ missing_controls = set(design['control_id']) - set(design['sample_id'])
+
+ if len(missing_controls) > 0:
+ logger.error('Missing control experiments: %s', list(missing_controls))
+ raise Exception("Missing control experiments: %s" % list(missing_controls))
+
+
+def check_files(design, fastq, paired):
+ '''Check if design file has the files found.'''
+
+ logger.info("Running file check.")
+
+ if paired: # paired-end data
+ files = list(design['fastq_read1']) + list(design['fastq_read2'])
+ else: # single-end data
+ files = design['fastq_read1']
+
+ files_found = fastq['name']
+
+ missing_files = set(files) - set(files_found)
+
+ if len(missing_files) > 0:
+ logger.error('Missing files from design file: %s', list(missing_files))
+ raise Exception("Missing files from design file: %s" % list(missing_files))
+ else:
+ file_dict = fastq.set_index('name').T.to_dict()
+
+ design['fastq_read1'] = design['fastq_read1'] \
+ .apply(lambda x: file_dict[x]['path'])
+ if paired: # paired-end data
+ design['fastq_read2'] = design['fastq_read2'] \
+ .apply(lambda x: file_dict[x]['path'])
+ return design
+
+
+def main():
+ args = get_args()
+
+ # Create a file handler
+ handler = logging.FileHandler('design.log')
+ logger.addHandler(handler)
+
+ # Read files
+ design_file = pd.read_csv(args.design, sep='\t')
+ fastq_file = pd.read_csv(args.design, sep='\t', names=['name', 'path'])
+
+ # Check design file
+ check_design_headers(design_file, args.paired)
+ check_controls(design_file)
+ new_design = check_files(design_file, fastq_file, args.paired)
+
+ # Write out new design file
+ new_design.to_csv('design.tsv', header=True, index=False)
+
+
+if __name__ == '__main__':
+ main()
diff --git a/workflow/tests/test_check_design.py b/workflow/tests/test_check_design.py
new file mode 100644
index 0000000000000000000000000000000000000000..394d5251b382b682bf758debdedd12aaf5637551
--- /dev/null
+++ b/workflow/tests/test_check_design.py
@@ -0,0 +1,103 @@
+#!/usr/bin/env python3
+
+import os
+import pytest
+import pandas as pd
+from io import StringIO
+import check_design
+import sys
+
+
+DESIGN_STRING = """sample_id\tbiosample\tfactor\ttreatment\treplicate\tcontrol_id\tfastq_read1
+A_1\tLiver\tH3K27ac\tNone\t1\tB_1\tA_1.fastq.gz
+A_2\tLiver\tH3K27ac\tNone\t2\tB_2\tA_2.fastq.gz
+B_1\tLiver\tInput\tNone\t1\tB_1\tB_1.fastq.gz
+B_2\tLiver\tInput\tNone\t2\tB_2\tB_2.fastq.gz
+"""
+
+FASTQ_STRING = """
+A_1.fastq.gz\t/path/to/file/A_1.fastq.gz
+A_2.fastq.gz\t/path/to/file/A_2.fastq.gz
+B_1.fastq.gz\t/path/to/file/B_1.fastq.gz
+B_2.fastq.gz\t/path/to/file/B_2.fastq.gz
+"""
+
+
+@pytest.fixture
+def design():
+ design_file = StringIO(DESIGN_STRING)
+ design_df = pd.read_csv(design_file, sep="\t")
+ return design_df
+
+
+@pytest.fixture
+def fastq_files():
+ fastq_file = StringIO(FASTQ_STRING)
+ fastq_df = pd.read_csv(fastq_file, sep='\t', names=['name', 'path'])
+ return fastq_df
+
+
+@pytest.fixture
+def design_1(design):
+ design_df = design.drop('fastq_read1', axis=1)
+ return design_df
+
+
+@pytest.fixture
+def design_2(design):
+ # Drop Control B_1
+ design_df = design.drop(design.index[2])
+ return design_df
+
+@pytest.fixture
+def design_3(design):
+ # Drop A_2 and B_2 and append as fastq_read2
+ design_df = design.drop(design.index[[1,3]])
+ design_df['fastq_read2'] = design.loc[[1,3],'fastq_read1'].values
+ return design_df
+
+
+@pytest.fixture
+def fastq_files_1(fastq_files):
+ # Drop B_2.fastq.gz
+ fastq_df = fastq_files.drop(fastq_files.index[3])
+ return fastq_df
+
+
+def test_check_headers_singleend(design_1):
+ paired = False
+ with pytest.raises(Exception) as excinfo:
+ check_design.check_design_headers(design_1, paired)
+ assert str(excinfo.value) == "Missing column headers: ['fastq_read1']"
+
+
+def test_check_headers_pairedend(design):
+ paired = True
+ with pytest.raises(Exception) as excinfo:
+ check_design.check_design_headers(design, paired)
+ assert str(excinfo.value) == "Missing column headers: ['fastq_read2']"
+
+
+def test_check_controls(design_2):
+ with pytest.raises(Exception) as excinfo:
+ check_design.check_controls(design_2)
+ assert str(excinfo.value) == "Missing control experiments: ['B_1']"
+
+
+def test_check_files_missing_files(design, fastq_files_1):
+ paired = False
+ with pytest.raises(Exception) as excinfo:
+ new_design = check_design.check_files(design, fastq_files_1, paired)
+ assert str(excinfo.value) == "Missing files from design file: ['B_2.fastq.gz']"
+
+
+def test_check_files_output_singleend(design, fastq_files):
+ paired = False
+ new_design = check_design.check_files(design, fastq_files, paired)
+ assert new_design.loc[0,'fastq_read1'] == "/path/to/file/A_1.fastq.gz"
+
+
+def test_check_files_output_pairedend(design_3, fastq_files):
+ paired = True
+ new_design = check_design.check_files(design_3, fastq_files, paired)
+ assert new_design.loc[0,'fastq_read2'] == "/path/to/file/A_2.fastq.gz"