add parser

Makefile

@@ -2,3 +2,6 @@ test: unittest
 
 unittest:
 	pytest --doctest-modules --last-failed --durations=3
+
+style:
+	autoflake

chunksum/parser.py

@@ -0,0 +1,63 @@
+def parse_chunks(data):
+    alg_name, chunks = data.split('!')
+    if chunks:
+        chunks = [c.split(':') for c in chunks.split(',') if c]
+        chunks = [(id, int(size)) for id, size in chunks]
+        return alg_name, chunks
+    else:
+        return alg_name, []
+
+
+def parse_line(line):
+    """
+    >>> from pprint import pprint
+    >>> pprint(parse_line('sum1  ./a  fck0sha2!'))
+    {'alg_name': 'fck0sha2', 'checksum': 'sum1', 'chunks': [], 'path': './a'}
+    >>> pprint(parse_line('sum2  ./file1  fck0sha2!abcd:10'))
+    {'alg_name': 'fck0sha2',
+     'checksum': 'sum2',
+     'chunks': [('abcd', 10)],
+     'path': './file1'}
+    >>> pprint(parse_line('sum3  ./file2  fck0sha2!bad:20,beef:30'))
+    {'alg_name': 'fck0sha2',
+     'checksum': 'sum3',
+     'chunks': [('bad', 20), ('beef', 30)],
+     'path': './file2'}
+    """
+    items = line.split('  ')
+    checksum = items[0]
+    chunks = items[-1]
+    if len(items) > 3:
+        path = '  '.join(items[1:-1])
+    else:
+        path = items[1]
+    alg_name, chunks = parse_chunks(chunks)
+    return dict(checksum=checksum,
+                path=path,
+                alg_name=alg_name,
+                chunks=chunks)
+
+
+def parse_chunksums(file):
+    """
+    >>> from pprint import pprint
+    >>> import io
+    >>> pprint(list(parse_chunksums(io.StringIO('''
+    ... sum1  ./a  fck0sha2!
+    ... sum2  ./file1  fck0sha2!abcd:10
+    ... sum3  ./file2  fck0sha2!bad:20,beef:30'''))))
+    [{'alg_name': 'fck0sha2', 'checksum': 'sum1', 'chunks': [], 'path': './a'},
+     {'alg_name': 'fck0sha2',
+      'checksum': 'sum2',
+      'chunks': [('abcd', 10)],
+      'path': './file1'},
+     {'alg_name': 'fck0sha2',
+      'checksum': 'sum3',
+      'chunks': [('bad', 20), ('beef', 30)],
+      'path': './file2'}]
+    """
+    for line in file:
+        line = line.strip()
+        if not line:
+            continue
+        yield parse_line(line)