polycubed: set peers after all cubes are created

When a list of cubes is created this is possible that a port in a cube has as
peer another port in a cube that hasn't been created yet, this causes an
exception that aborts the port's creation.

This commit strips the port's peer and sets them after all cubes are created.

Fixes: fbf9bc9 ("add /cubes/ creation api")
Signed-off-by: Mauricio Vasquez B <mauriciovasquezbernal@gmail.com>

Author: mauriciovasquezbernal

src/polycubed/src/polycubed_core.h

@@ -39,6 +39,7 @@ namespace polycubed {
 class RestServer;
 
 class PolycubedCore {
+  friend class RestServer;
  public:
   PolycubedCore(BaseModel *base_model);
   ~PolycubedCore();

src/polycubed/src/rest_server.cpp

@@ -436,21 +436,34 @@ void RestServer::post_cubes(const Pistache::Rest::Request &request,
                                Pistache::Http::ResponseWriter response) {
   logRequest(request);
   try {
-    json j = json::parse(request.body());
-    logJson(j);
+    json cubes = json::parse(request.body());
+    logJson(cubes);
+    /*
+     * This is possible that a cube's port has as peer another port
+     * of a cube that hasn't been created yet.  This logic removes all
+     * the peers from the request and sets them after all cubes have
+     * been created.
+     */
+    auto peers = utils::strip_port_peers(cubes);
     std::vector<Response> resp = {{ErrorTag::kNoContent, nullptr}};
     bool error = false;
-    for (auto &it : j) {
-      resp = core.get_service_controller(it["service-name"]).get_management_interface()->get_service()
-              ->CreateReplaceUpdate(it["name"], it, false, true);
+
+    for (auto &cube : cubes) {
+      resp = core.get_service_controller(cube["service-name"]).get_management_interface()->get_service()
+              ->CreateReplaceUpdate(cube["name"], cube, false, true);
       if (!error && resp[0].error_tag != kCreated) {
         Rest::Server::ResponseGenerator::Generate(std::move(resp), std::move(response));
         error = true;
       }
     }
+
     if (!error) {
       Rest::Server::ResponseGenerator::Generate(std::move(resp), std::move(response));
     }
+
+    for (auto &[peer1, peer2] : peers) {
+      core.try_to_set_peer(peer1, peer2);
+    }
   } catch (const std::runtime_error &e) {
     logger->error("{0}", e.what());
     response.send(Pistache::Http::Code::Bad_Request, e.what());

src/polycubed/src/utils/utils.cpp

@@ -44,6 +44,29 @@ bool check_kernel_version(const std::string &version) {
          KERNEL_VERSION(major_r, minor_r, patch_r);
 }
 
+std::map<std::string, std::string> strip_port_peers(json &cubes) {
+  std::map<std::string, std::string> peers;
+
+  for (auto &cube : cubes) {
+    if (!cube.count("ports")) {
+      continue;
+    }
+
+    auto &ports = cube.at("ports");
+
+    for (auto &port : ports) {
+      if (port.count("peer")) {
+        auto cube_name = cube.at("name").get<std::string>();
+        auto port_name = port.at("name").get<std::string>();
+        peers[cube_name + ":" + port_name] = port.at("peer").get<std::string>();
+        port.erase("peer");
+      }
+    }
+  }
+
+  return peers;
+}
+
 }  // namespace utils
 }  // namespace polycubed
 }  // namespace polycube

src/polycubed/src/utils/utils.h

@@ -15,12 +15,17 @@
  */
 
 #include <string>
+#include <map>
+#include "polycube/services/json.hpp"
+
+using json = nlohmann::json;
 
 namespace polycube {
 namespace polycubed {
 namespace utils {
 
 bool check_kernel_version(const std::string &version);
+std::map<std::string, std::string> strip_port_peers(json &cubes);
 
 }  // namespace utils
 }  // namespace polycubed