diff --git a/plugins/UM3NetworkPrinting/tests/Cloud/TestCloudApiClient.py b/plugins/UM3NetworkPrinting/tests/Cloud/TestCloudApiClient.py
new file mode 100644
index 0000000000..328bb053b7
--- /dev/null
+++ b/plugins/UM3NetworkPrinting/tests/Cloud/TestCloudApiClient.py
@@ -0,0 +1,136 @@
+# Copyright (c) 2018 Ultimaker B.V.
+# Copyright (c) 2018 Ultimaker B.V.
+# Cura is released under the terms of the LGPLv3 or higher.
+import json
+from typing import Dict, Tuple
+from unittest import TestCase, mock
+from unittest.mock import patch, MagicMock
+
+from PyQt5.QtCore import QByteArray
+from PyQt5.QtNetwork import QNetworkAccessManager, QNetworkReply
+
+from UM.Application import Application
+from UM.Signal import Signal
+from cura.CuraApplication import CuraApplication
+from plugins.UM3NetworkPrinting.src.Cloud.CloudApiClient import CloudApiClient
+from plugins.UM3NetworkPrinting.src.Cloud.Models import CloudCluster, CloudErrorObject
+
+# This mock application must extend from Application and not QtApplication otherwise some QObjects are created and
+# a segfault is raised.
+class FixtureApplication(Application):
+    def __init__(self):
+        super().__init__(name = "test", version = "1.0", api_version = "5.0.0")
+        super().initialize()
+        Signal._signalQueue = self
+
+    def functionEvent(self, event):
+        event.call()
+
+    def parseCommandLine(self):
+        pass
+
+    def processEvents(self):
+        pass
+
+    def getRenderer(self):
+        return MagicMock()
+
+class ManagerMock:
+    finished = Signal()
+    authenticationRequired = Signal()
+
+    def __init__(self, reply):
+        self.reply = reply
+
+    def get(self, request):
+        self.reply.url.return_value = request.url()
+
+        return self.reply
+
+class ManagerMock2:
+    finished = Signal()
+    authenticationRequired = Signal()
+
+    def get(self, request):
+        reply_mock = MagicMock()
+        reply_mock.url = request.url
+        reply_mock.operation.return_value = QNetworkAccessManager.GetOperation
+        return reply_mock
+
+    @staticmethod
+    def createReply(method: str, url: str, status_code: int, response: dict):
+        reply_mock = MagicMock()
+        reply_mock.url().toString.return_value = url
+        reply_mock.operation.return_value = {
+            "GET": QNetworkAccessManager.GetOperation,
+            "POST": QNetworkAccessManager.PostOperation,
+            "PUT": QNetworkAccessManager.PutOperation,
+            "DELETE": QNetworkAccessManager.DeleteOperation,
+            "HEAD": QNetworkAccessManager.HeadOperation,
+        }[method]
+        reply_mock.attribute.return_value = status_code
+        reply_mock.readAll.return_value = json.dumps(response).encode()
+        return reply_mock
+
+
+class TestCloudApiClient(TestCase):
+
+    app = CuraApplication.getInstance() or CuraApplication
+
+    def _errorHandler(self, errors: [CloudErrorObject]):
+        pass
+
+    @patch("cura.NetworkClient.QNetworkAccessManager")
+    @patch("cura.API.Account")
+    def test_GetClusters(self, account_mock, manager_mock):
+        reply_mock = MagicMock()
+        reply_mock.operation.return_value = 2
+        reply_mock.attribute.return_value = 200
+        reply_mock.readAll.return_value = b'{"data": [{"cluster_id": "RIZ6cZbWA_Ua7RZVJhrdVfVpf0z-MqaSHQE4v8aRTtYq", "host_guid": "e90ae0ac-1257-4403-91ee-a44c9b7e8050", "host_name": "ultimakersystem-ccbdd30044ec", "host_version": "5.1.2.20180807", "is_online": false, "status": "inactive"}, {"cluster_id": "R0YcLJwar1ugh0ikEZsZs8NWKV6vJP_LdYsXgXqAcaNC", "host_guid": "e90ae0ac-1257-4403-91ee-a44c9b7e8050", "host_name": "ultimakersystem-ccbdd30044ec", "host_version": "5.1.2.20180807", "is_online": true, "status": "active"}]}'
+        manager_mock.return_value = ManagerMock(reply_mock)
+        account_mock.isLoggedIn.return_value = True
+
+        result = []
+
+        def _callback(clusters):
+            result.extend(clusters)
+
+        with mock.patch.object(Application, "getInstance", new = lambda: FixtureApplication()):
+            api = CloudApiClient(account_mock, self._errorHandler)
+            api.getClusters(_callback)
+
+        manager_mock.return_value.finished.emit(reply_mock)
+
+        self.assertEqual(2, len(result))
+
+    @patch("cura.NetworkClient.QNetworkAccessManager")
+    @patch("cura.API.Account")
+    def test_GetClusters2(self, account_mock, manager_mock):
+        manager = ManagerMock2()
+        manager_mock.return_value = manager
+        account_mock.isLoggedIn.return_value = True
+
+        result = []
+
+        # with mock.patch.object(Application, "getInstance", new = lambda: FixtureApplication()):
+        api = CloudApiClient(account_mock, self._errorHandler)
+        api.getClusters(lambda clusters: result.extend(clusters))
+
+        manager.finished.emit(ManagerMock2.createReply(
+            "GET", "https://api-staging.ultimaker.com/connect/v1/clusters",
+            200, {
+                "data": [{
+                    "cluster_id": "RIZ6cZbWA_Ua7RZVJhrdVfVpf0z-MqaSHQE4v8aRTtYq",
+                    "host_guid": "e90ae0ac-1257-4403-91ee-a44c9b7e8050",
+                    "host_name": "ultimakersystem-ccbdd30044ec", "host_version": "5.1.2.20180807",
+                    "is_online": False, "status": "inactive"
+                }, {
+                    "cluster_id": "R0YcLJwar1ugh0ikEZsZs8NWKV6vJP_LdYsXgXqAcaNC",
+                    "host_guid": "e90ae0ac-1257-4403-91ee-a44c9b7e8050",
+                    "host_name": "ultimakersystem-ccbdd30044ec", "host_version": "5.1.2.20180807",
+                    "is_online": True, "status": "active"
+                }]
+            }
+        ))
+
+        self.assertEqual(2, len(result))