Add an error message when Docker container is not ready to be started. Ref #1281.

gns3server/compute/docker/docker_vm.py

@@ -352,7 +352,11 @@ class DockerVM(BaseNode):
     def start(self):
         """Starts this Docker container."""
 
-        state = yield from self._get_container_state()
+        try:
+            state = yield from self._get_container_state()
+        except DockerHttp404Error:
+            raise DockerError("Docker container '{name}' with ID {cid} does not exist or is not ready yet. Please try again in a few seconds.".format(name=self.name,
+                                                                                                                                                      cid=self._cid))
         if state == "paused":
             yield from self.unpause()
         elif state == "running":

gns3server/compute/vmware/__init__.py

@@ -396,12 +396,12 @@ class VMware(BaseManager):
         try:
             stdout_data, _ = yield from asyncio.wait_for(process.communicate(), timeout=timeout)
         except asyncio.TimeoutError:
-            raise VMwareError("vmrun has timed out after {} seconds!\nTry to run {} in a terminal to see more informations.\n\nMake sure GNS3 and VMware run under the same user and whitelist vmrun.exe in your antivirus.".format(timeout, command_string))
+            raise VMwareError("vmrun has timed out after {} seconds!\nTry to run {} in a terminal to see more details.\n\nMake sure GNS3 and VMware run under the same user and whitelist vmrun.exe in your antivirus.".format(timeout, command_string))
 
         if process.returncode:
             # vmrun print errors on stdout
             vmrun_error = stdout_data.decode("utf-8", errors="ignore")
-            raise VMwareError("vmrun has returned an error: {}\nTry to run {} in a terminal to see more informations.\nAnd make sure GNS3 and VMware run under the same user.".format(vmrun_error, command_string))
+            raise VMwareError("vmrun has returned an error: {}\nTry to run {} in a terminal to see more details.\nAnd make sure GNS3 and VMware run under the same user.".format(vmrun_error, command_string))
 
         return stdout_data.decode("utf-8", errors="ignore").splitlines()