address norm's comments

Author: philasmar

src/Amazon.Extensions.Configuration.SystemsManager/AppConfig/AppConfigProcessor.cs

@@ -84,11 +84,13 @@ public async Task<IDictionary<string, string>> GetDataAsync()
 
             if(_appConfigDataClient != null)
             {
-                return await GetDataFromServiceAsync().ConfigureAwait(false);
+                return await GetDataFromServiceAsync().ConfigureAwait(false) 
+                       ?? new Dictionary<string, string>();
             }
             else
             {
-                return await GetDataFromLambdaExtensionAsync().ConfigureAwait(false);
+                return await GetDataFromLambdaExtensionAsync().ConfigureAwait(false) 
+                       ?? new Dictionary<string, string>();
             }
         }
 

src/Amazon.Extensions.Configuration.SystemsManager/Internal/SystemsManagerProcessor.cs

@@ -63,7 +63,7 @@ private async Task<IDictionary<string, string>> GetParametersByPathAsync()
                 {
                     var response = await client.GetParametersByPathAsync(new GetParametersByPathRequest { Path = Source.Path, Recursive = true, WithDecryption = true, NextToken = nextToken, ParameterFilters = Source.Filters }).ConfigureAwait(false);
                     nextToken = response.NextToken;
-                    parameters.AddRange(response.Parameters);
+                    parameters.AddRange(response.Parameters ?? new List<Parameter>());
                 } while (!string.IsNullOrEmpty(nextToken));
 
                 return AddPrefix(Source.ParameterProcessor.ProcessParameters(parameters, Source.Path), Source.Prefix);