WIP: Implement terminate signal to C++ and Python servers

lib/umbridge.h

@@ -271,6 +271,22 @@ namespace umbridge {
       return supportsApplyHessian;
     }
 
+    void terminate(const json& config_json = json::parse("{}")) {
+      json request_body;
+      request_body["name"] = name;
+
+      if (!config_json.empty())
+        request_body["config"] = config_json;
+
+      if (auto res = cli.Post("/Terminate", headers, request_body.dump(), "application/json")) {
+        json response_body = parse_result_with_error_handling(res);
+        std::string status = response_body["status"].get<std::string>();
+        std::cout << status << std::endl;
+      } else {
+        throw std::runtime_error("POST Terminate failed with error type '" + to_string(res.error()) + "'");
+      }
+    }
+
   private:
 
     mutable httplib::Client cli;
@@ -693,6 +709,19 @@ namespace umbridge {
       res.set_content(response_body.dump(), "application/json");
     });
 
+    svr.Post("/Terminate", [&](const httplib::Request &req, httplib::Response &res) {
+      json request_body = json::parse(req.body);
+      Model& model = get_model_from_name(models, request_body["name"]);
+      json empty_default_config;
+      json config_json = request_body.value("config", empty_default_config);
+
+      json response_body;
+      svr.stop();
+      response_body["status"] = "Model server terminated.";
+
+      res.set_content(response_body.dump(), "application/json");
+    });
+
     std::cout << "Listening on port " << port << "..." << std::endl;
 
 #ifdef LOGGING

umbridge/um.py

@@ -2,6 +2,7 @@
 import requests
 import asyncio
 from concurrent.futures import ThreadPoolExecutor
+import signal
 
 class Model(object):
 
@@ -156,6 +157,14 @@ def apply_hessian(self, out_wrt, in_wrt1, in_wrt2, parameters, sens, vec, config
             raise Exception(f'Model returned error of type {response["error"]["type"]}: {response["error"]["message"]}')
         return response["output"]
 
+    def terminate(self):
+        inputParams = {}
+        inputParams["name"] = self.name
+
+        response = requests.post(f"{self.url}/Terminate", json=inputParams).json()
+        print(response["status"])
+
+
 def serve_models(models, port=4242, max_workers=1, error_checks=True):
 
     model_executor = ThreadPoolExecutor(max_workers=max_workers)
@@ -437,6 +446,23 @@ async def info(request):
         return web.json_response(response_body)
 
 
+    @routes.post('/Terminate')
+    async def terminate(request):
+        req_json = await request.json()
+        model_name = req_json["name"]
+        model = get_model_from_name(model_name)
+
+        if model is None:
+            return model_not_found_response(req_json["name"])
+
+        print("Sending SIGTERM to model server")
+        signal.raise_signal(signal.SIGTERM)
+
+        return web.Response(text="{\"status\": \"Model server terminated.\"}")
+
+
+
+
     app = web.Application(client_max_size=None)
     app.add_routes(routes)
     web.run_app(app, port=port)