1 files changed, 144 insertions, 0 deletions
diff --git a/python/filter_groupworks.py b/python/filter_groupworks.py
new file mode 100755
index 0000000..bbba770
--- /dev/null
+++ b/python/filter_groupworks.py
@@ -0,0 +1,144 @@
+#!/usr/bin/env python3
+"""
+Filters an input stream of sorted "groupworks" scalding job, and outputs
+"good enough" matches to be merged in fatcat.
+
+Output is JSON lines which are arrays of releases that could/should be merged
+together, either as multiple releases under a single work, or releases merged
+into a single entity (via redirects).
+
+Note that releases *should* only end up on a single line, and only once per
+line!
+
+No dependencies (only python3 stdlib)
+
+Note: the actual importer/merger should filter the following patterns out:
+- container title has "letter" and "diar"
+- contribs (authors) contain "&NA;"
+- dates differ (not just year)
+"""
+
+import sys
+import json
+
+# out of 1000
+SCORE_THRESHOLD = 900
+
+MAX_SLUG_LINES = 50
+
+REQUIRE_AUTHORS = False
+
+def tokenize(s, remove_whitespace=False):
+
+    s.replace('&apos;', "'")
+    # Remove non-alphanumeric characters
+    s = ''.join([c for c in s.lower() if c.isalnum() or c.isspace()])
+
+    if remove_whitespace:
+        s = ''.join(s.split())
+
+    # Encode as dumb ASCII (TODO: this is horrible)
+    return s.encode('ascii', 'replace').replace(b'?', b'')
+
+def check_authors(left, right):
+    """
+    Intended to check GROBID extracted authors (right) against "known good"
+    (but maybe not perfect) Crossref metadata authors ("left").
+    """
+    if not left and not right:
+        return bool(not REQUIRE_AUTHORS)
+    if len(left) != len(right):
+        return False
+    right_all = tokenize(" ".join(right))
+    for i in range(len(left)):
+        l = left[i].lower().replace('jr.', '').split()
+        if not l:
+            return False
+        l = tokenize(l[-1])
+        if len(l) <= 1:
+            # weird author name (single char)
+            return False
+        if l not in right_all:
+            #print("MISSING: {} from {}".format(l.decode('utf8'), right_all.decode('utf8')))
+            return False
+    return True
+
+def test_check_authors():
+    assert check_authors([], []) == bool(not REQUIRE_AUTHORS)
+    assert not check_authors([], ['one'])
+    assert check_authors(['one'], ['one'])
+    assert check_authors(['one two'], ['One Two'])
+    assert check_authors(['two'], ['One Two'])
+    assert check_authors(['two'], ['two, one'])
+    assert check_authors(['mago'], ['Mr. Magoo'])
+    assert check_authors(['Mr. Magoo'], ['Mr Magoo'])
+    assert check_authors(['one', 'tw', 'thr'], ['one', 'two', 'three'])
+
+# Rows are (score, left, right)
+def process_group(rows):
+
+    # first pass reduces size of list and generates a linkage graph
+    filtered = list()
+    for row in rows:
+        score = int(row[0])
+        if score < SCORE_THRESHOLD:
+            continue
+        left = json.loads(row[1])
+        right = json.loads(row[2])
+        # authors must roughly match
+        if not check_authors(left['authors'], right['authors']):
+            continue
+        # years must match (if defined)
+        if left['year'] and right['year'] and left['year'] != right['year']:
+            continue
+        filtered.append((left, right))
+
+    if not filtered:
+        return
+
+    # second pass finds a connected graph and returns that
+    releases = dict()
+    group_ids = set()
+    for row in filtered[1:]:
+        (left, right) = row
+        l_id = left['fatcat_release']
+        r_id = right['fatcat_release']
+        releases[l_id] = left
+        releases[r_id] = right
+        if not group_ids:
+            group_ids.add(l_id)
+            group_ids.add(r_id)
+            continue
+        if l_id in group_ids or r_id in group_ids:
+            group_ids.add(l_id)
+            group_ids.add(r_id)
+            continue
+
+    if not group_ids:
+        return
+
+    print(json.dumps([releases[ident] for ident in group_ids]))
+
+def run():
+
+    last_slug = None
+    lines = []
+
+    # group lines by slug, and process in batches
+    for line in sys.stdin:
+        line = line.strip().split('\t')
+        assert len(line) == 4
+        slug = line[0]
+        if last_slug and slug != last_slug and lines:
+            if len(lines) <= MAX_SLUG_LINES:
+                process_group(lines)
+            lines = []
+        last_slug = slug
+        lines.append(line[1:])
+
+    # catch any remaining
+    if lines:
+        process_group(lines)
+
+if __name__=='__main__':
+    run()