Suppress output when generating schema

Author: nevillelyh

python/coglet/schema.py

@@ -10,8 +10,16 @@ def main():
         print(f'Usage {os.path.basename(sys.argv[0])} <MODULE> <CLASS>')
         sys.exit(1)
 
+    # Some libraries print progress upon import and mess up schema JSON
+    _stdout_write = sys.stdout.write
+    _stderr_write = sys.stderr.write
+    sys.stdout.write = lambda out: len(out)
+    sys.stderr.write = lambda out: len(out)
     p = inspector.create_predictor(sys.argv[1], sys.argv[2])
     s = schemas.to_json_schema(p)
+    sys.stdout.write = _stdout_write
+    sys.stderr.write = _stderr_write
+
     print(json.dumps(s, indent=2))