adds sql formatter

pre_commit_hooks/format_sql.py

@@ -0,0 +1,35 @@
+import sys
+import click
+import os
+import sqlparse
+
+options = {"keyword_case": "upper", "comma_first": True}
+
+
+
+def reformat(sql_file):
+    with open(sql_file, "r") as f:
+        original = f.read()
+    new = sqlparse.format(original, **options)
+    with open(sql_file, "w") as f:
+        f.write(new)
+    if new == original:
+        return 0
+    else:
+        return 1
+
+
+@click.command()
+@click.option('--directory', required=True)
+def main(directory):
+    res = 0
+    for root, dirs, files in os.walk(directory):
+        for f in files:
+            if f.split('.')[-1] == 'sql':
+                res = max(res, reformat(os.path.join(root, f)))
+                print(f"reformatted {f}")
+    return res
+
+
+if __name__ == "__main__":
+    sys.exit(main())