Parallelize getChildEpisodesAsync

Source/AudibleUtilities/ApiExtended.cs

@@ -121,93 +121,25 @@ namespace AudibleUtilities
 
 			Serilog.Log.Logger.Debug("Begin initial library scan");
 
+			List<Task<List<Item>>> getChildEpisodesTasks = new();
+
 			await foreach (var item in Api.GetLibraryItemAsyncEnumerable(libraryOptions))
 			{
 				if (item.IsEpisodes && importEpisodes)
 				{
-					var children = await getEpisodeChildrenAsync(item);
+					//Get child episodes asynchronously and await all at the end
-
+					getChildEpisodesTasks.Add(getChildEpisodesAsync(item));
-					// actual individual episode, not the parent of a series.
-					// for now I'm keeping it inside this method since it fits the work flow, incl. importEpisodes logic
-					if (!children.Any())
-					{
-						items.Add(item);
-						continue;
-					}
-
-					foreach (var child in children)
-					{
-						// use parent's 'DateAdded'. DateAdded is just a convenience prop for: PurchaseDate.UtcDateTime
-						child.PurchaseDate = item.PurchaseDate;
-						// parent is essentially a series
-						child.Series = new Series[]
-						{
-							new Series
-							{
-								Asin = item.Asin,
-								// This should properly be Single() not FirstOrDefault(), but FirstOrDefault is defensive for malformed data from audible
-								Sequence = item.Relationships.FirstOrDefault(r => r.Asin == child.Asin).Sort.ToString(),
-								Title = item.TitleWithSubtitle
-							}
-						};
-						// overload (read: abuse) IsEpisodes flag
-						child.Relationships = new Relationship[]
-						{
-							new Relationship
-							{
-								RelationshipToProduct = RelationshipToProduct.Child,
-								RelationshipType = RelationshipType.Episode
-							}
-						};
-					}
-					items.AddRange(children);
 				}
 				else if (!item.IsEpisodes)
 					items.Add(item);
 			}
 
+			//asait and all all episides from all parents
+			foreach (var epList in await Task.WhenAll(getChildEpisodesTasks))
+				items.AddRange(epList);
+
 			Serilog.Log.Logger.Debug("Scan complete");
 
-#if DEBUG
-//System.IO.File.WriteAllText(library_json, AudibleApi.Common.Converter.ToJson(items));
-#endif
-
-			var validators = new List<IValidator>();
-			validators.AddRange(getValidators());
-			foreach (var v in validators)
-			{
-				var exceptions = v.Validate(items);
-				if (exceptions is not null && exceptions.Any())
-					throw new AggregateException(exceptions);
-			}
-
-			return items;
-		}
-
-		private async Task<List<Item>> getItemsAsync2(LibraryOptions libraryOptions, bool importEpisodes)
-		{
-			var items = new List<Item>();
-#if DEBUG
-	//// this will not work for multi accounts
-	//var library_json = "library.json";
-	//library_json = System.IO.Path.GetFullPath(library_json);
-	//if (System.IO.File.Exists(library_json))
-	//{
-	//    items = AudibleApi.Common.Converter.FromJson<List<Item>>(System.IO.File.ReadAllText(library_json));
-	//}
-#endif
-
-			Serilog.Log.Logger.Debug("Begin initial library scan");
-
-			if (!items.Any())
-				items = await Api.GetAllLibraryItemsAsync(libraryOptions);
-
-			Serilog.Log.Logger.Debug("Initial library scan complete. Begin episode scan");
-
-			await manageEpisodesAsync(items, importEpisodes);
-
-			Serilog.Log.Logger.Debug("Episode scan complete");
-
 #if DEBUG
 //System.IO.File.WriteAllText(library_json, AudibleApi.Common.Converter.ToJson(items));
 #endif
@@ -225,63 +157,23 @@ namespace AudibleUtilities
 		}
 
 		#region episodes and podcasts
-		private async Task manageEpisodesAsync(List<Item> items, bool importEpisodes)
+		
+		private async Task<List<Item>> getChildEpisodesAsync(Item parent)
 		{
-			// add podcasts and episodes to list. If fail, don't let it de-rail the rest of the import
+			var children = await getEpisodeChildrenAsync(parent);
-			try
+
+			// actual individual episode, not the parent of a series.
+			// for now I'm keeping it inside this method since it fits the work flow, incl. importEpisodes logic
+			if (!children.Any())
+				return new List<Item>() { parent };
+
+			foreach (var child in children)
 			{
-				// get parents
+				// use parent's 'DateAdded'. DateAdded is just a convenience prop for: PurchaseDate.UtcDateTime
-				var parents = items.Where(i => i.IsEpisodes).ToList();
+				child.PurchaseDate = parent.PurchaseDate;
-#if DEBUG
+				// parent is essentially a series
-//var parentsDebug = parents.Select(i => i.ToJson()).Aggregate((a, b) => $"{a}\r\n\r\n{b}");
+				child.Series = new Series[]
-//System.IO.File.WriteAllText("parents.json", parentsDebug);
-#endif
-
-				if (!parents.Any())
-					return;
-
-				Serilog.Log.Logger.Information($"{parents.Count} series of shows/podcasts found");
-
-				// remove episode parents. even if the following stuff fails, these will still be removed from the collection
-				items.RemoveAll(i => i.IsEpisodes);
-
-				if (importEpisodes)
 				{
-					// add children
-					var children = await getEpisodesAsync(parents);
-					Serilog.Log.Logger.Information($"{children.Count} episodes of shows/podcasts found");
-					items.AddRange(children);
-				}
-			}
-			catch (Exception ex)
-			{
-				Serilog.Log.Logger.Error(ex, "Error adding podcasts and episodes");
-			}
-		}
-
-		private async Task<List<Item>> getEpisodesAsync(List<Item> parents)
-		{
-			var results = new List<Item>();
-
-			foreach (var parent in parents)
-			{
-				var children = await getEpisodeChildrenAsync(parent);
-
-				// actual individual episode, not the parent of a series.
-				// for now I'm keeping it inside this method since it fits the work flow, incl. importEpisodes logic
-				if (!children.Any())
-				{
-					results.Add(parent);
-					continue;
-				}
-
-				foreach (var child in children)
-				{
-					// use parent's 'DateAdded'. DateAdded is just a convenience prop for: PurchaseDate.UtcDateTime
-					child.PurchaseDate = parent.PurchaseDate;
-					// parent is essentially a series
-					child.Series = new Series[]
-					{
 						new Series
 						{
 							Asin = parent.Asin,
@@ -289,22 +181,18 @@ namespace AudibleUtilities
 							Sequence = parent.Relationships.FirstOrDefault(r => r.Asin == child.Asin).Sort.ToString(),
 							Title = parent.TitleWithSubtitle
 						}
-					};
+				};
-					// overload (read: abuse) IsEpisodes flag
+				// overload (read: abuse) IsEpisodes flag
-					child.Relationships = new Relationship[]
+				child.Relationships = new Relationship[]
-					{
+				{
 						new Relationship
 						{
 							RelationshipToProduct = RelationshipToProduct.Child,
 							RelationshipType = RelationshipType.Episode
 						}
-					};
+				};
-				}
-
-				results.AddRange(children);
 			}
-
+			return children;
-			return results;
 		}
 
 		private async Task<List<Item>> getEpisodeChildrenAsync(Item parent)