I have an MVC Web App and a Web API Service that I am trying to retrieve information from. The problem is in the CapitalMailOrders entity collection is missing items when it is deserialized on the web side.
The Service uses the below to retrieve the information
var result = db.Contacts
.Include(a => a.IDXPageLinks)
.Include(b => b.ReboGatewayLoginInfoes)
.Include(c => c.SocialMedias)
.Include(d => d.WebSiteInfoes)
.Include(e => e.ContactImages)
.Include(f => f.RealtorSetUpProcesses.Select(f1 => f1.CapitalMailOrders)
.Include(g => g.Contact_CarrierCode_Assignments)
.FirstOrDefault(c => c.ContactID == id);
This code is good and returns the below on the service side. The below image shows 3 CapitalMailOrders which is what there should be.
But when it's deserialized on the Web side I only get 2 the 3rd is null
here is the Web Side Repository Code
public Contact Get(int id)
{
var responseStream =
requestMethod.GetResponseStream(
requestMethod.getRequest("GET", "application/json",
string.Format("{0}/api/contact/{1}", restService, id)).GetResponse());
var contacts = deSerialize<Contact>(responseStream) as Contact;
return contacts;
}
deSerialize is in the base repository class
public class BaseRepository
{
protected readonly string restService = ConfigurationManager.AppSettings["restService"];
protected readonly RequestMethod requestMethod = new RequestMethod();
protected ISerialization _serializer;
protected BaseRepository()
{ }
protected object deSerialize<T>(Stream stream)
{
var retval = _serializer.DeSerialize<T>(stream);
return retval;
}
protected string serialize<T>(T value)
{
var retval = _serializer.Serialize<T>(value);
return retval;
}
}
public class JsonNetSerialization : ISerialization
{
public string Serialize<T>(object o)
{
return JsonConvert.SerializeObject((T)o);
}
public object DeSerialize<T>(Stream stream)
{
return JsonConvert.DeserializeObject<T>(new StreamReader(stream).ReadToEnd());
}
}
Any ideas? Thanks
This post pointed me to the problem and suggested solution. In a nutshell the poster #Darin advised to return the data collection from the web api using models rather than the entity collection. Since there is no databinding to the db context when serializing the data back to the web app theres really no reason to carry the overhead and problems of trying to serialize the entity collection. This blog post goes into more detail.
Related
I am working on/extending TOH. I have an add method that wants to push the new Hero onto the array then return user to the list.
the result of the call to addHero is coming back as a JSON hero inside double ticks, so as a string.
i have read many articles which seem to point to
angular.toJson
or
.map(response=> response.JSON())
These are not working.
Here is the excerpt from my heroes.component.ts
add(name: string): void {
name = name.trim();
if (!name) { return; }
this.heroService.addHero({ name } as Hero)
.subscribe(hero =>
{
this.heroes.push(hero);
this.location.go('/Heroes');
}
);
}
and hero.service.ts
This clearly returns a Hero object...
addHero (hero: Hero): Observable<Hero> {
return this.http.post<Hero>(this.heroesUrl, hero, httpOptions).pipe(
tap((hero: Hero) => console.log(`added hero w/ id=${hero.id}`)),
catchError(this.handleError<Hero>('addHero'))
);
}
Upon return, the result is successfully pushed to the array, but enclosed in quotes.
The UI evidence of this is that the list has a blank entry at the bottom because there is no .Name property on that final array element.
If i refresh the page, everyone gets loaded as json.
Simple question but I can not seem to find an answer. Have been through many S/O questions involving ng2, php, etc. but none seem to address ng6, or provide a clue I can take away. if they do, Im missing it.
If you want to parse a json into a javascript object you can use JSON.parse(response.JSON())
I'm guessing response.JSON() is returning the response as json, which then needs to be parsed
Edit: you can probably just remove the map => response.JSON() . As angular httpClient already parses it
The issue was the return type of the routine in the service.
#youris question got me to look harder at the service.
The issue is that the default response is not coded correctly as utf8 and 'text/html'
Here is the corrected code.
Public Function add(mh As mHero) As CustomJsonStringResult
Dim h As New TOHbos.Hero()
h.name.Value = mh.name
h.Save()
Return JsonStringResultExtension.JSONString(Me, h.JSON, HttpStatusCode.OK)
End Function
the referenced JsonStringResultExtension is credited to #NKosi in this post. (Code included for ease of referece)
Web Api: recommended way to return json string
public static class JsonStringResultExtension {
public static CustomJsonStringResult JsonString(this ApiController controller, string jsonContent, HttpStatusCode statusCode = HttpStatusCode.OK) {
var result = new CustomJsonStringResult(controller.Request, statusCode, jsonContent);
return result;
}
public class CustomJsonStringResult : IHttpActionResult {
private string json;
private HttpStatusCode statusCode;
private HttpRequestMessage request;
public CustomJsonStringResult(HttpRequestMessage httpRequestMessage, HttpStatusCode statusCode = HttpStatusCode.OK, string json = "") {
this.request = httpRequestMessage;
this.json = json;
this.statusCode = statusCode;
}
public Task<HttpResponseMessage> ExecuteAsync(CancellationToken cancellationToken) {
return Task.FromResult(Execute());
}
private HttpResponseMessage Execute() {
var response = request.CreateResponse(statusCode);
response.Content = new StringContent(json, Encoding.UTF8, "application/json");
return response;
}
}
}
Making these changes, the result is json, its pushed to the array correctly, and shows up in the Heroes list correctly.
I am writing a WebAPICore to return the JSON objects from the database. For unknown reason, the properties are returned as camelCase by default.
I have checked the SQL Script and it does return the correct case for the DataFields. But when I consume the service, the properties of the objects are changed to camelCase automatically.
For example, OfferingID is returned as offeringID
The existing Return JSON object
{
"offeringID": 120842,
"courseCode": "FLTE2A1F/1",
"courseName": "FLT - E2 Certificate in Skills for Working Life (Animals) (QCF)"
}
The format which I want to return
{
"OfferingID": 120842,
"CourseCode": "FLTE2A1F/1",
"CourseName": "FLT - E2 Certificate in Skills for Working Life (Animals) (QCF)"
}
The Model - Offering:
public class Offering
{
[Key]
public int OfferingID { get; set; }
public string CourseCode { get; set; }
public string CourseName { get; set; }
}
My WebAPI Controller Get Method
[HttpGet("{id}")]
public async Task<IActionResult> GetOfferingDetail(int id)
{
var obj = await _context.Offerings.FromSql("dbo.GetOfferingDetail #p0", id).SingleOrDefaultAsync();
if (obj == null)
return NotFound("ID not found");
return new ObjectResult(obj);
}
Configure Services Method in Startup.cs:
public void ConfigureServices(IServiceCollection services)
{
services.AddDbContext<DbContexts.OakCommonsDbContext>(options => options.UseSqlServer(Configuration.GetConnectionString("MyConnection")));
services.AddCors(options => options.AddPolicy("AllowAll", p => p.AllowAnyOrigin()
.AllowAnyMethod()
.AllowAnyHeader()));
var mvccore = services.AddMvc();
mvccore.AddJsonOptions(o => o.SerializerSettings.NullValueHandling = Newtonsoft.Json.NullValueHandling.Ignore);
}
Could you please advise me how I could return JSON Objects in the Exact Case as I defined in the Model?
Here is the working code. By default, WebAPI Core is going to use CamelCasePropertyNamesContractResolver(). You need to change it to DefaultContractResolver to render as you defined in the Model.
And DefaultContractResolver is under Newtonsoft.Json.Serialization namespace.
services.AddMvc()
.AddJsonOptions(o => o.SerializerSettings.NullValueHandling = Newtonsoft.Json.NullValueHandling.Ignore)
.AddJsonOptions(o => o.SerializerSettings.ContractResolver = new Newtonsoft.Json.Serialization.DefaultContractResolver());
I am trying to use Web API to grab certain fields from my MVC controller. I can't seem to match the right type with the right list. I am fine with converting everything to string.
I either get an error in code (can not convert types), or if I get it to compile, I get this error:
"The 'ObjectContent`1' type failed to serialize the response body for content type 'application/xml; charset=utf-8'."
From other similar posts, people responded with how to create a list, but not with the declaration of the return value of the Get. Please include both.
Also I would prefer not to add additional controllers as I need to do this on a number of my models.
Here is my code--note you can see I tried a number of different ways:
public class APICLIENTsController : ApiController
{
private ApplicationDbContext db = new ApplicationDbContext();
// GET api/<controller>
public IEnumerable<string> Get()
//public IEnumerable<CLIENT> Get()
{
//return db.CLIENTs.OrderBy(x => x.CLIENTNAME).ToList();
string[] listOfUsers = db.CLIENTs.OrderBy(x => x.CLIENTNAME).Select(r => new
{
ID = r.CLIENTID.ToString(),
NAME = r.CLIENTNAME
});
return listOfUsers.ToList();
//return db.CLIENTs.Select(x => new { x.CLIENTNAME }).ToArray();
}
If you want to return JSON use the
JsonResult
type.
public JsonResult Get()
{
//return db.CLIENTs.OrderBy(x => x.CLIENTNAME).ToList();
string[] listOfUsers = db.CLIENTs.OrderBy(x => x.CLIENTNAME).Select(r => new
{
ID = r.CLIENTID.ToString(),
NAME = r.CLIENTNAME
});
return Json(listOfUsers.ToList(), JsonRequestBehavior.AllowGet);
}
Your query is returning a collection of anonymous objects, not string[] so it will throw an exception. Even if you were to generate string[] by concatenating the CLIENTID and CLIENTNAME properties, it would be a little use to the client.
Create a model to represent what you need to return to the view
public class ClientVM
{
public int ID { get; set; }
public string Name { get; set; }
}
and modify your method to
public IEnumerable<ClientVM> Get()
{
IEnumerable<ClientVM> model = db.CLIENTs.OrderBy(x => x.CLIENTNAME).Select(r => new ClientVM
{
ID = r.CLIENTID,
Name = r.CLIENTNAME
});
return model;
}
Side note: depending on how your calling and consuming this in the client, you may need to change the Content-Type to specifically return json (refer these answers for more detail)
First off my question is very similar to below however I'm not sure if the answers are applicable to my specific problem or whether I just need clarification about how to approach it:
Convert LinkedHashMap<String,String> to an object in Java
I am using struts2 json rest plugin to convert a json array into a java array. The array is sent through an ajax post request and the java receives this data. However instead of being the object type I expect it is received as a LinkedHashmap. Which is identical to the json request in structure.
[
{advance_Or_Premium=10000, available=true},
{advance_Or_Premium=10000, available=true},
{advance_Or_Premium=10000, available=true}
]
The data is all present and correct but just in the wrong type. Ideally I want to send the data in my object type or if this is not possible convert the LinkedHashMap from a list of keys and values into the object array. Here is the class I am using, incoming data is received in the create() method:
#Namespace(value = "/rest")
public class OptionRequestAction extends MadeAbstractAction implements ModelDriven<ArrayList<OptionRequestRest>>
{
private String id;
ArrayList<OptionRequestRest> model = new ArrayList<OptionRequestRest>();
public HttpHeaders create()
{
// TODO - need to use model here but it's a LinkedHashmap
return new DefaultHttpHeaders("create");
}
public String getId()
{
return this.id;
}
public ArrayList<OptionRequestRest> getModel()
{
return this.model;
}
public ArrayList<OptionRequestRest> getOptionRequests()
{
#SuppressWarnings("unchecked")
ArrayList<OptionRequestRest> lReturn = (ArrayList<OptionRequestRest>) this.getSession().get("optionRequest");
return lReturn;
}
// Handles /option-request GET requests
public HttpHeaders index()
{
this.model = this.getOptionRequests();
return new DefaultHttpHeaders("index").lastModified(new Date());
}
public void setId(String pId)
{
this.id = pId;
}
public void setModel(ArrayList<OptionRequestRest> pModel)
{
this.model = pModel;
}
// Handles /option-request/{id} GET requests
public HttpHeaders show()
{
this.model = this.getOptionRequests();
return new DefaultHttpHeaders("show").lastModified(new Date());
}
}
One of the things which is confusing me is that this code works fine and returns the correct object type if the model is not an array. Please let me know if my question is not clear enough and needs additional information. Thanks.
I'm new at MVC and can't get this to work. I basically have a Users class, a UserRepository, and a IUser interface.
This is my code:
public class Users
{
public string UserName { get; set; }
public string Department { get; set; }
public string UserType { get; set; }
}
public class UsersRepository : TimeAttendanceMVC.Models.IUsers
{
public Users Return_UserName_Dept()
{
Users U = new Users();
List<Users> LoggedInUser = new List<Users>();
U.UserName = "TestUser";
U.Department = "Finance";
U.UserType = "Administrator";
LoggedInUser.Add(U);
//string json = JsonConvert.SerializeObject(LoggedInUser, Formatting.Indented);
//return json;
return Json(LoggedInUser.ToArray(), JsonRequestBehavior.AllowGet);
}
}
namespace TimeAttendanceMVC.Models
{
public class IUsers
{
List<Users> Return_UserName_Dept();
}
}
There are a few errors that I get. In UsersRepository.cs where i'm returning Json, the error says that "The name Json does not exist in the current context". The error from IUsers.cs is that "Return_UserName_Dept() must declare a body because it is not marked abstract...".
Can anybody please help me with this. I just don't know how this is supposed to work and i'm trying to learn MVC by working on this application. It's actually the FullCalendar application found here - link to FullCalendar. I'm trying to turn it into an MVC application.
EDIT:
Maybe I need to do this:
public JsonResult Return_UserName_Dept()
instead of public Users Return_UserName_Dept()
You should be doing this on your controller in some method which returns a json action (jsonresult). The repository should be returning your data only and all the operations you need to do, whether you're converting data to json or any other logic should happen at the controller or at some helper class which would be called by the controller..
Edit:
In order to have a method which returns a JsonResult, you need to have a reference to System.Web.Mvc.ActionResult and since the repository is usually at the model, you won't have this reference.. another thing is that you might be breaking your design the logic should be available at the controller for what you want
Edit 2:
The code below is from an old post you can see here. Note how the action PopulateDetails gets the user object from the repository and that's all the repository does.. the actual logic is happening inside this method, such as populate the rest of the UserModel class, and then it returns the JsonResult:
public JsonResult PopulateDetails(UserModel model)
{
UserResultModel userResultModel = new UserResultModel();
if (String.IsNullOrEmpty(model.UserId))
{
userResultModel.Message = "UserId can not be blank";
return Json(userResultModel);
}
User user = _userRepository.GetUser(model.UserId);
if (user == null)
{
userResultModel.Message = String.Format("No UserId found for {0}", model.UserId);
return Json(userResultModel);
}
userResultModel.LastName = user.LastName;
userResultModel.FirstName = user.FirstName;
userResultModel.Message = String.Empty; //success message is empty in this case
return Json(userResultModel);
}