From fd8358acae09dabee2abfdbec40144b2c0d83ab8 Mon Sep 17 00:00:00 2001
From: Mat Gadd <source@catchall.drarok.com>
Date: Tue, 18 Jun 2019 11:33:07 +0100
Subject: [PATCH] Fix infinite recursion in swagger.py for circular models,
 fixes #190

---
 flask_restplus/swagger.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/flask_restplus/swagger.py b/flask_restplus/swagger.py
index d98cb5d0..e85a24d4 100644
--- a/flask_restplus/swagger.py
+++ b/flask_restplus/swagger.py
@@ -550,6 +550,8 @@ def register_model(self, model):
         if name not in self.api.models:
             raise ValueError('Model {0} not registered'.format(name))
         specs = self.api.models[name]
+        if name in self._registered_models:
+            return ref(model)
         self._registered_models[name] = specs
         if isinstance(specs, ModelBase):
             for parent in specs.__parents__: