I want to push and get Recipe-Data from my Firebase Database in Xamarin.Forms with the Firesharp Plugin.
My Model Class is the Recipe Class:
public class Recipe
{
public string title { get; set; }
public string workTime { get; set; }
public string degreeOfDifficulty { get; set; }
public string caloriesPerPerson { get; set; }
public string preparation { get; set; }
public string cookingBakingTime { get; set; }
public string restTime { get; set; }
public int portions { get; set; }
public string pictureSource { get; set; }
public List<Ingredient> ingredients { get; set; }
public Recipe()
{
ingredients = new List<Ingredient>();
}
}
So Push Recipe-Objects to the Firebase DB works:
public async Task PushRecipe(Recipe recipe)
{
IFirebaseClient client = new FirebaseClient(config);
client.Push("Recipes", recipe);
}
Firebase Example
But when i want to get Data from the Database i get an Error..
public async Task<List<Recipe>> GetAllRecipes()
{
IFirebaseClient client = new FirebaseClient(config);
FirebaseResponse response = await client.GetAsync("Recipes");
try
{
List<Recipe> recipelist = response.ResultAs<List<Recipe>>();
return recipelist;
} catch (Exception e){
}
return null;
}
After this:
List<Recipe> recipelist = response.ResultAs<List<Recipe>>();
this Exception comes..
"{Newtonsoft.Json.JsonSerializationException: Cannot deserialize the current JSON object (e.g. {"name":"value"}) into type 'System.Collections.Generic.List`1[dignaBon_App.Models.Recipe]' because the type requires a JSON array (e.g. [1,2,3]) to deserialize correc…}"
I don´t understand why i can´t get Data from the Database back..
Can someone help me?
You need instatiate the "config" with your firebase secret address key. Go to your Firebase console for this.
Related
I have these classes
public class Project
{
public Guid Id { get; set; }
public string DeployUrl { get; set; }
public List<Technology> Techs { get; set; } = new();
}
public class Technology
{
public Guid Id { get; set; }
public string Name { get; set; }
public string TechImg { get; set; }
[JsonIgnore]
public List<Project> Projects { get; set; } = new();
[JsonIgnore]
public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
}
Which creates a many-to-many relationship. I want to add an endpoint to create a Project. The main issue here is the approach with which i'll do it. Since I don't send the full Technology object to the frontend, it would be impossible to send back a full Project as the request body for the endpoint since its Technology property would be missing fields, which posses an incompatibility with the actual entity in my server. Of course that the Technology instance already exists. So, what is the best approach here? Currently I'm sending a Project DTO that doesn't contain a List<Technology> but a List<Guid> of technologies, and in my repository I fetch from the DB all those technologies and add them manually. Is this correct? Thanks in advance.
public class ProjectPostDto
{
public string DeployUrl { get; set; }
public List<Guid> TechsIds { get; set; } = new();
}
public async Task<ActionResult> PostProject(ProjectPostDto projectDto)
{
try
{
Project newProject = FromPostDto(projectDto);
newProject.Techs = await Service.GetTechs(projectDto.TechsIds);
await Service.Create(newProject);
ProjectPostDto newProjectDto = ToPostDto(newProject);
return CreatedAtAction(nameof(GetProject), new { id = newProject.Id }, newProjectDto);
} catch (Exception)
{
return StatusCode(500, "Server error");
}
}
I have a problem with generic types in X++. I need to deserialize a JSON list yet everything I tried failed. Like using IEnumerables and JsonSerializer(does it find only AX classes and can't see references library classes?).
My helper class is in a C# library and I only need to get access to values inside the response JSON that are in list. How can I archive this in X++?
//X++
defaultException defaultException= new defaultException();
defaultException= JsonConvert::DeserializeObject(response, defaultException.GetType()); <- this gives is correct yet I cant use the values in the list
//values = FormJsonSerializer::deserializeCollection(classnum(List), response, Types::Class, 'defaultException');
// C#
public class defaultException
{
public MyException exception { get; set; }
}
public class MyException
{
public string serviceCtx { get; set; }
public string serviceCode { get; set; }
public string serviceName { get; set; }
public string timestamp { get; set;}
public string referenceNumber { get; set; }
public List<exceptionDetailList> exceptionDetailList { get; set; }
}
public class exceptionDetailList
{
public int exceptionCode { get; set; }
public string exceptionDescription { get; set; }
}
Found a solution. If we have another list in this list we need to recreate the enumerator in loop again and again as needed.
defaultException defaultException = new defaultException();
defaultException = JsonConvert::DeserializeObject(batch, defaultException.GetType());
System.Collections.IEnumerable exceptionList = defaultException.exception.exceptionDetailList;
System.Collections.IEnumerator enumerator = exceptionList.GetEnumerator();
while (enumerator.MoveNext())
{
exceptionDetailList exceptionDetailList = new exceptionDetailList();
exceptionDetailList = enumerator.Current;
}
Im trying to create a persistent sqllite db (creation tables once you install the app, deletion of db when you uninstall app)
I have a issue that I cant save my sub objects for example
public class ObjectInstanceResponseModel : GenericResponseModel
{
public ObservableCollection<ObjectInstanceData> ObjectInstances { get; set; }
}
public class ObjectInstanceData : GenericResponseModel
{
[PrimaryKey, AutoIncrement]
public int Id { get; set; }
[JsonProperty("idObjectinstance")]
public int IdObjectInstance { get; set; }
[JsonProperty("objectclass_idObjectclass")]
public int ObjectClassIdObjectClass { get; set; }
[JsonProperty("objectclassname")]
public string ObjectClassName { get; set; }
[JsonProperty("visibilitylevel")]
public int VisibilityLevel { get; set; }
[JsonProperty("showname")]
public bool ShowName { get; set; }
[JsonProperty("showicon")]
public bool ShowIcon { get; set; }
[JsonProperty("creationtime")]
public DateTimeOffset CreationTime { get; set; }
[JsonProperty("users_idUsers")]
public int UsersIdUsers { get; set; }
[JsonProperty("isfavorite")]
public bool? IsFavorite { get; set; }
[OneToMany("ObjectInstanceDataStrings")]
[JsonProperty("strings")]
public List<String> Strings { get; set; }
}
public class String
{
[PrimaryKey, AutoIncrement]
[JsonProperty("idObjectparameterstring")]
public int? IdObjectParameterString { get; set; }
[ForeignKey(typeof(ObjectInstanceData))]
public int ObjectInstanceDataStrings { get; set; }
[JsonProperty("stringvalue")]
public string StringValue { get; set; }
[JsonProperty("objectparameterset_idObjectparameterset")]
public int? ObjectParameterSetIdObjectParameterSet { get; set; }
[JsonProperty("showinballon")]
public bool? ShowInBallon { get; set; }
[JsonProperty("idClassparameter")]
public int IdClassParameter { get; set; }
[JsonProperty("classparametername")]
public string ClassParameterName { get; set; }
}
So, my class String is always empty, although there are some rows in the table that I created Strings..
Am I need a lazy loading for this?
I implemented sqllite through depedency service in my app.cs like this:
public partial class App : Application
{
public static SQLiteConnection DatabaseConnection { get; set; }
public App()
{
InitializeComponent();
DatabaseConnection = DependencyService.Get<IConnection>().GetConnection();
CreateTables();
}
private void CreateTables()
{
DatabaseConnection.CreateTable<ObjectInstanceData>();
DatabaseConnection.CreateTable<Models.Objects.String>();
}
protected override void OnStart()
{
}
protected override void OnSleep()
{
}
protected override void OnResume()
{
}
}
So, basically the logic should be when no internet, work with sql lite (keep local changes), and when internet come back upload that changes that kept in db, and erase data from tables.
You noticed that Im using response model for api.
So, Im calling from my FavoriteObjectViewModel this:
var response = await ApiServiceProvider.GetObjectInstances(null, true);
and in the ApiServiceProvider:
public static async Task<ObjectInstanceResponseModel> GetObjectInstances(string queryString = null, bool? onlyFavorites = null)
{
HttpResponseMessage response;
response = await apiClient.GetAsync(objectInstancesEndpoint);
var resultContent = await response.Content.ReadAsStringAsync();
var result = JsonConvert.DeserializeObject<ObservableCollection<ObjectInstanceData>>(resultContent);
objectInstanceResponse.ObjectInstances = result;
//after each api call I need to update db
//delete previous data, and add fresh data from api
App.DatabaseConnection.DeleteAll<ObjectInstanceData>();
foreach (var item in result)
{
App.DatabaseConnection.Insert(item);
if (item.Strings != null && item.Strings.Count > 0)
App.DatabaseConnection.InsertAll(item.Strings);
}
//I only get the data for ObjectInstanceData, Strings model is empty!
var objectsResponseDb = App.DatabaseConnection.GetAllWithChildren<ObjectInstanceData>();
objectInstanceResponse.Succeeded = true;
return objectInstanceResponse;
}
So, my questions are:
If I create tables each time in App.cs is that mean, that I not store data, when user quit application, and re-enter again?
Why is the model Strings empty? When I invoke var strings = App.DatabaseConnection.GetAllWithChildren<Models.Objects.String>(); I can see that there is data?
What is the best approach for doing offline "logging"? maybe there is a some better nuget for sqllite?
I don't know much about persistent databases but one thing I can tell you for sure:you're approach is wrong.
You should create a separate class for the database's logic like creating tables and instantiating the connection along with other methods for manipulating data.
In the App class you can create a static resource of the database class which you can call it and make use of the methods in it.
I'm not very good with explaining but here it is a very basic example of how it should look:https://learn.microsoft.com/en-us/xamarin/get-started/tutorials/local-database/?tutorial-step=2&tabs=vswin.
In my ASP.NET Core Web API I have an entity Idea:
public class Idea
{
public int Id { get; set; }
public string Name { get; set; }
public string OwnerId { get; set; }
public User Owner { get; set; }
public string Description { get; set; }
public int? MainPhotoId { get; set; }
public Photo MainPhoto { get; set; }
public int? MainVideoId { get; set; }
public Video MainVideo { get; set; }
public ICollection<Photo> Photos { get; set; }
public ICollection<Video> Videos { get; set; }
public ICollection<Audio> Audios { get; set; }
public ICollection<Document> DocumentsAboutTheIdea { get; set; }
public DateTime DateOfPublishing { get; set; }
}
public class Photo
{
public int Id { get; set; }
public string Url { get; set; }
}
(the different media-type classes are equivalent)
When the client makes a Post request for creating the Idea he sends the information about it along with all the media-files (I am using IFormFile and IFormFileCollection) and while saving them on the server I set the Url property to match their location. But in the Get request I want to send the files (not Urls).
Here is the Get action which now returns only one file (mainPhoto) without any JSON and without any other media-files:
[HttpGet("{id}", Name = "Get")]
public async Task<IActionResult> Get(int id)
{
var query = await unitOfWork.IdeaRepository.GetByIdAsync(id, includeProperties: "Owner,MainPhoto,MainVideo,Photos,Videos,Audios,DocumentsAboutTheIdea");
if (query != null)
{
string webRootPath = hostingEnvironment.WebRootPath;
var path = string.Concat(webRootPath, query.MainPhoto.Url);
var memory = new MemoryStream();
using (var stream = new FileStream(path, FileMode.Open))
{
await stream.CopyToAsync(memory);
}
memory.Position = 0;
return File(memory, GetContentType(path), Path.GetFileName(path));
}
return NotFound();
}
So in a Get request I want to send to the client side (an Angular app) some of the information about the Idea in a JSON-format ALONG WITH different (NOT ONE) media-files associated with it. My goal is to make the client side get it all so that it can then show them on the page of the info about the Idea. But I cannot figure out the approach for this. Is there a way to achieve this? Or there is another (better) way of interacting with the client side to transfer all the required data? I tried to find information on this topic but couldn't find any.
Let me preface this question with, I am VERY new to ASP.NET Core/EF Core.
My model look like this:
namespace MyProject.Models
{
public class DeviceContext : DbContext
{
public DeviceContext(DbContextOptions<DeviceContext> options) : base(options) { }
public DbSet<Device> Devices { get; set; }
public DbSet<DeviceLocation> DeviceLocations { get; set; }
}
public class Device
{
public int Id { get; set; }
public string DeviceName { get; set; }
public string ServerName { get; set; }
public string MacAddress { get; set; }
public string LastUpdate { get; set; }
public string WiredIPAddress { get; set; }
public string WirelessIPAddress { get; set; }
public DeviceLocation DeviceLocation { get; set; }
}
public class DeviceLocation
{
public int Id { get; set; }
public string Location { get; set; }
public virtual ICollection<Device> Devices { get; set; }
}
}
I would like to be able to fetch a specific Device based on DeviceName, but I would also like to fetch ALL the devices in a particular Location.
I think the following would work for the first question:
var _Devices = DeviceContext.Devices.FirstOrDefault(d => d.DeviceName == "BLA");
I am just having a hard time getting the second query to run. Ideally, the output would be rendered to JSON to be consumed by an API. I would like the output to look something like this:
{
"Locations": {
"NYC": ["ABC", "123"],
"Boston": ["DEF", "456"],
"Chicago": ["GHI", "789"]
}
}
UPDATE
If I use the following code, it give me the following error:
Code:
// Grouping by ProfileName
var devices = DeviceContext.DeviceLocations.Include(n => n.Device).ToList();
var result = new { success = true, message = "Successfully fetched Devices", data = devices };
return JsonConvert.SerializeObject(result);
Error:
Additional information: Self referencing loop detected for property 'DeviceLocation' with type 'Project.Models.DeviceLocation'. Path 'data[0].Device[0]'.
You can try as shown below.
Note : Use Eager Loading with Include.
using System.Data.Entity;
var devicesList = DeviceContext.DeviceLocations.Where(d=>d.Location = "Your-Location-Name")
.Include(p => p.Devices)
.ToList();
Update :
var devicesList = DeviceContext.DeviceLocations
.Include(p => p.Devices)
.ToList();