better error handling when fetching remote config from Alerta API (#178)

Author: v-zhuravlev

alertaclient/config.py

@@ -1,9 +1,11 @@
-
+import json
 import configparser
 import os
 
 import requests
 
+from alertaclient.exceptions import ClientException
+
 default_config = {
     'config_file': '~/.alerta.conf',
     'profile': None,
@@ -54,8 +56,11 @@ def get_remote_config(self, endpoint=None):
         config_url = '{}/config'.format(endpoint or self.options['endpoint'])
         try:
             r = requests.get(config_url, verify=self.options['sslverify'])
+            r.raise_for_status()
             remote_config = r.json()
         except requests.RequestException as e:
-            raise
+            raise ClientException("Failed to get config from {}. Reason: {}".format(config_url, e))
+        except json.decoder.JSONDecodeError: 
+            raise ClientException("Failed to get config from {}: Reason: not a JSON object".format(config_url))
 
         self.options = {**remote_config, **self.options}

tests/test_remoteconfig.py

@@ -0,0 +1,114 @@
+
+import unittest
+import requests
+import requests_mock
+from requests_mock import Adapter
+from alertaclient.cli import Config
+from alertaclient.exceptions import ClientException
+
+
+class RemoteConfigTestCase(unittest.TestCase):
+
+    def setUp(self):
+        self.adapter = Adapter()
+        self.config = Config("")
+        self.remote_json_config = """
+          {
+            "actions": [],
+            "alarm_model": {
+              "name": "Alerta 6.7.5"
+            },
+            "audio": {
+              "new": null
+            },
+            "auth_required": false,
+            "azure_tenant": null,
+            "client_id": null,
+            "colors": {
+              "highlight": "skyblue ",
+              "severity": {
+                "cleared": "#00CC00",
+                "critical": "red",
+                "debug": "#9D006D",
+                "indeterminate": "lightblue",
+                "informational": "#00CC00",
+                "major": "orange",
+                "minor": "yellow",
+                "normal": "#00CC00",
+                "ok": "#00CC00",
+                "security": "blue",
+                "trace": "#7554BF",
+                "unknown": "silver",
+                "warning": "dodgerblue"
+              },
+              "text": "black"
+            },
+            "columns": ["severity", "status", "lastReceiveTime",
+                        "duplicateCount",
+                        "customer", "environment", "service", "resource",
+                        "event", "value", "text"],
+            "customer_views": false,
+            "dates": {
+              "longDate": "d/M/yyyy h:mm:ss.sss a",
+              "mediumDate": "EEE d MMM HH:mm",
+              "shortTime": "HH:mm"
+            },
+            "email_verification": false,
+            "endpoint": "http://localhost:8080/api",
+            "github_url": "https://github.com",
+            "gitlab_url": "https://gitlab.com",
+            "keycloak_realm": null,
+            "keycloak_url": null,
+            "pingfederate_url": null,
+            "provider": "basic",
+            "refresh_interval": 5000,
+            "severity": {
+              "cleared": 5,
+              "critical": 1,
+              "debug": 7,
+              "indeterminate": 5,
+              "informational": 6,
+              "major": 2,
+              "minor": 3,
+              "normal": 5,
+              "ok": 5,
+              "security": 0,
+              "trace": 8,
+              "unknown": 9,
+              "warning": 4
+            },
+            "signup_enabled": true,
+            "site_logo_url": "",
+            "sort_by": "lastReceiveTime",
+            "tracking_id": null
+          }
+          """
+
+    @requests_mock.mock()
+    def test_config_success(self, m):
+        """Tests successful remote config fetch"""
+        m.get('/api/config', text=self.remote_json_config, status_code=200)
+        self.config.get_remote_config('http://localhost:8080/api')
+        self.assertEqual(self.config.options['alarm_model']['name'], 'Alerta 6.7.5')
+
+    @requests_mock.mock()
+    def test_config_timeout(self, m):
+        m.get('/api/config', exc=requests.exceptions.ConnectTimeout)
+        with self.assertRaises(ClientException):
+            self.config.get_remote_config('http://localhost:8080/api')
+
+    @requests_mock.mock()
+    def test_config_not_found(self, m):
+
+        m.get('/config', status_code=404)
+        with self.assertRaises(ClientException):
+            self.config.get_remote_config('http://localhost:8080')
+
+    @requests_mock.mock()
+    def test_config_not_json(self, m):
+        """Tests that URL is accessible (HTTP 200)
+        but there is no Alerta API config in JSON"""
+
+        m.get('/sometext/config', text="Some random text", status_code=200)
+        with self.assertRaises(ClientException):
+            self.config.get_remote_config('http://localhost:8080/sometext')