/// <summary> /// Creates WorkItem, create a comment and add to the Comments property. Then add the WorkItem to the DbContext /// </summary> /// <param name="wiContext"></param> /// <returns></returns> private static async Task GenerateWorkItemWithComment2(WorkItemDbContext wiContext) { var workItem = new WorkItem { Id = Guid.NewGuid(), Title = "Some work item" }; var comment = new WorkItemComment { Id = Guid.NewGuid(), Comment = "Some comment", }; workItem.Comments.Add(comment); // Add workitem to DbSet with comments wiContext.WorkItems.Add(workItem); // WORKS: Generates two inserts await wiContext.SaveChangesAsync(); var saved = await GetWorkItem(wiContext, workItem.Id); if (saved.Comments.Count != 1) { throw new InvalidOperationException("WorkItem should have one comment"); } }
/// <summary> /// Simulates a disconnected scenario - Creates a work item in a dbContext. Then uses a different Context, loads the WorkItem /// and tries to add a comment to the Comments property. /// </summary> /// <param name="wiContext"></param> private static async Task GenerateWorkItemWithComment3(WorkItemDbContext wiContext) { var workItem = new WorkItem { Id = Guid.NewGuid(), Title = "Some work item" }; // Save the workItem first with the passed in DbContext // Like a request to an endpoint "CreateWorkItem" wiContext.WorkItems.Add(workItem); await wiContext.SaveChangesAsync(); // simulates a "disconnected scenario" where I only want to add a comment // Like a request to an endpoint "AddComment" using (var newContext = new WorkItemDbContext()) { var existingWorkItem = await newContext.WorkItems.Include(wi => wi.Comments) .FirstAsync(wi => wi.Id == workItem.Id); var comment = new WorkItemComment { Id = Guid.NewGuid(), Comment = "SOme comment", }; existingWorkItem.Comments.Add(comment); // State is "Unchanged" var workItemState = newContext.Entry(existingWorkItem).State; // State is "Detached" var state2 = newContext.Entry(comment).State; // Fails await newContext.SaveChangesAsync(); } var saved = await GetWorkItem(wiContext, workItem.Id); if (saved.Comments.Count != 1) { throw new InvalidOperationException("WorkItem should have one comment"); } }
/// <summary> /// Creates/Saves the WorkItem first then use the same instance and add a comment to the Comments property /// </summary> /// <param name="wiContext"></param> /// <returns></returns> private static async Task GenerateWorkItemWithComment1(WorkItemDbContext wiContext) { var workItem = new WorkItem { Id = Guid.NewGuid(), Title = "Some work item" }; // Save the workItem first wiContext.WorkItems.Add(workItem); await wiContext.SaveChangesAsync(); var comment = new WorkItemComment { Id = Guid.NewGuid(), Comment = "Some comment", }; // Add the comment to the saved comment instance workItem.Comments.Add(comment); // State is unchanged var workItemState = wiContext.Entry(workItem).State; // PROBLEM: The comment has a state of Modified. var state2 = wiContext.Entry(comment).State; // Call fails with UPDATE comment instead of insert await wiContext.SaveChangesAsync(); var saved = await GetWorkItem(wiContext, workItem.Id); if (saved.Comments.Count != 1) { throw new InvalidOperationException("WorkItem should have one comment"); } }