minor tidies

src/FilterLists.Agent/Logger.cs

@@ -18,6 +18,8 @@ public Logger(string appInsightsKey)
         public void Dispose()
         {
             telemetryClient.Flush();
+
+            //https://docs.microsoft.com/en-us/azure/application-insights/app-insights-api-custom-events-metrics#flushing-data
             Thread.Sleep(5000);
         }
 

src/FilterLists.Agent/Program.cs

@@ -47,9 +47,9 @@ private static async Task TryCaptureSnapshots()
                 {
                     await CaptureSnapshots(BatchSize).TimeoutAfter(Timeout);
                 }
-                catch (TimeoutException)
+                catch (TimeoutException te)
                 {
-                    logger.Log("Timeout - Program.CaptureSnapshots()");
+                    logger.Log(te);
                 }
             }
         }

src/FilterLists.Services/Snapshot/Snapshot.cs

@@ -200,6 +200,8 @@ private void TrackException(Exception e)
         {
             telemetryClient.TrackException(e);
             telemetryClient.Flush();
+
+            //https://docs.microsoft.com/en-us/azure/application-insights/app-insights-api-custom-events-metrics#flushing-data
             Thread.Sleep(5000);
         }
     }

src/FilterLists.Services/UserAgentService.cs

@@ -16,24 +16,37 @@ public static class UserAgentService
             "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36";
 
         public static async Task<string> GetMostPopularString()
+        {
+            try
+            {
+                return await TryGetLatestMostPopularStringOrDefault();
+            }
+            catch (HttpRequestException)
+            {
+                return UaStringDefault;
+            }
+        }
+
+        private static async Task<string> TryGetLatestMostPopularStringOrDefault()
         {
             using (var httpClient = new HttpClient())
             {
                 var response = await httpClient.GetAsync(UaStringSource, HttpCompletionOption.ResponseHeadersRead);
+                response.EnsureSuccessStatusCode();
                 using (var stream = await response.Content.ReadAsStreamAsync())
                 using (var streamReader = new StreamReader(stream))
                 {
                     string line;
                     while ((line = await streamReader.ReadLineAsync()) != null)
                         if (line.Contains(UaStringSourceClass))
-                            return ParseUaString(line);
+                            return ParseUaStringOrDefault(line);
                 }
             }
 
             return UaStringDefault;
         }
 
-        private static string ParseUaString(string line)
+        private static string ParseUaStringOrDefault(string line)
         {
             var classIndex = line.IndexOf(UaStringSourceClass, StringComparison.Ordinal);
             var postClassIndexSubstring = line.Substring(classIndex);