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How to use POST request to create an object in C# API?

So I'm trying to make this parking ticket system and I'm currently creating these objects manually in the code for testing. Now I've come to the step where my POST request in postman should be able to create an object in the memory of the app. I've got two classes one for a ''Car'' and one for the ''Ticket''.
public class Car
{
public string regNr { get; set; }
public string carBrand { get; set; }
public string carColor { get; set; }
public List<Ticket> ticketlist {get; set;}
public Car()
{
this.ticketlist = new List<Ticket>();
}
public void addNewTicket(Ticket newTicket)
{
ticketlist.Add(newTicket);
}
}
}
public class Ticket
{
public int ticketID { get; set; } = 0;
public DateTime date { get; set; }
public string comment { get; set; }
public int parkingAreaID { get; set; }
public int parkingsOfficerID { get; set; }
}
}
List<Bil> list = new List<Car>();
public void Post([FromBody]Bil val)
{
list.Add(val);
}
The GET requests work and I want to be able to add a new ticket to a registration number by using my post request.
My current output is this;
{
"regNr": "BT66358",
"carBrand": "BMW",
"carColor": "Yellow",
"ticketlist": [
{
"ticketID": 1,
"date": "2020-12-12T17:49:34.4000401+01:00",
"comment": "very bad parking",
"parkingsAreaID": 1,
"parkingsOfficerID": 2
},
{
"ticketID": 2,
"date": "2020-12-12T17:49:34.4000401+01:00",
"comment": "very bad parking",
"parkingsAreaID": 2,
"parkingsOfficerID": 2
}
]
}
---------------UPDATE-----------
Bil = Car
botliste = ticketlist
liste = list
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/q3UaO.png

If I understood you correctly, then most likely you just need to add some attributes, and you get something like this:
List<Car> list = new List<Car>();
[HttpPost]
[HttpPost("SomeRoute")]
public IActionResult Post([FromBody] Car val)
{
if (val == null)
{
return BadRequest("Car data must be filled");
}
if (string.IsNullOrEmpty(val.regNr))
{
return BadRequest("Reg number must be filled");
}
var car = list.FirstOrDefault(c => string.Equals(c.regNr, val.regNr));
if (car != null)
{
car.ticketlist.AddRange(val.ticketlist);
}
else
{
list.Add(val);
}
/// And return IActionResult
return Ok();
}
P.S. Give a description of the Bil type to get a more detailed answer.
upd:
You can also add attributes to the fields of your classes that will validate the values, for example:
...
public class Car
{
[MinLength(6, ErrorMessage = "regNr field must be at least 6 characters")]
public string regNr { get; set; }
...
The "MinLength" attribute indicates that the value for this property is required, and must be at least 6 characters.
More details here: https://learn.microsoft.com/en-us/dotnet/api/system.componentmodel.dataannotations?view=net-5.0
upd2:
This is how I get to invoke this method:

Deserialize RESTSharp JSON Response

I'm working on a project to gather data from NOAA. I'm having trouble figuring out how to make the response usable.
This is what NOAA's API response looks like to my call:
{
"metadata": {
"resultset": {
"offset": 1,
"count": 38859,
"limit": 2
}
},
"results": [
{
"mindate": "1983-01-01",
"maxdate": "2019-12-24",
"name": "Abu Dhabi, AE",
"datacoverage": 1,
"id": "CITY:AE000001"
},
{
"mindate": "1944-03-01",
"maxdate": "2019-12-24",
"name": "Ajman, AE",
"datacoverage": 0.9991,
"id": "CITY:AE000002"
}
]
}
I used JSON2CSharp.com to convert the result set into my needed classes. Below is the relevant code:
public class NOAA
{
public class Resultset
{
public int offset { get; set; }
public int count { get; set; }
public int limit { get; set; }
}
public class Metadata
{
public Resultset resultset { get; set; }
}
public class Location
{
public string mindate { get; set; }
public string maxdate { get; set; }
public string name { get; set; }
public double datacoverage { get; set; }
public string id { get; set; }
}
public class RootObject
{
public Metadata metadata { get; set; }
public List<Location> results { get; set; }
}
public class Response
{
IList<Metadata> metadata;
IList<Location> results;
}
public void RestFactory(string Token, string Endpoint, Dictionary<string, string> Params)
{
// Initiate the REST request
var client = new RestClient("https://www.ncdc.noaa.gov/cdo-web/api/v2/" + Endpoint);
var request = new RestRequest(Method.GET);
// Add the token
request.AddHeader("token", Token);
// Add the parameters
foreach (KeyValuePair<string, string> entry in Params)
{
request.AddParameter(entry.Key, entry.Value);
}
// Execute the REST request
var response = client.Execute(request);
// Deserialize the response
Response noaa = new JsonDeserializer().Deserialize<Response>(response);
// Print to console
foreach (Location loc in noaa)
{
Console.WriteLine(loc.name);
}
}
}
At this point, I'm just trying to print the location name to reach my next learning milestone. I'm getting the error:
Severity Code Description Project File Line Suppression State
Error CS1579 foreach statement cannot operate on variables of type 'NOAA.Response' because 'NOAA.Response' does not contain a public instance definition for 'GetEnumerator'
Other than the error, I think I don't quite understand the proper approach since the response has more than one "layer". Guidance?

Your foreach loop is trying to call an iterator on the object itself, not the list inside it.
Try this instead
foreach (Location loc in noaa.results)
{
Console.WriteLine(loc.name);
}

I can tell you the cause of error. That is because noaa is not iterable. If you want to iterate over any object then it needs to implement IEnumerable interface. This is the reason because of which noaa is not iterable. noaa does not inherit this interface or implement it. Do you get the same error if you use noaa.results?

Return JSON from API method

I am using ASP.net Core web api (c#) here
I have a JSON string as:
{
"userId":321,
"account":"new
"fname":"Adam",
"lname":"Silver"
"features":[
{
"available":true,
"status":open,
"admin":false
}
]
}
I want to test this data in my angular code so wanted to hardcode this into my API; then I want my API to return this back. What I am finding it hard is how to return this. Shall I return this as a string or need to parse it?
I have this method in my API:
[HttpGet]
public ActionResult<IEnumerable<string>> Get()
{
return new string[] { "value1", "value2" };
}
Do I need to represent this into string or parse it someway?

Your JSON is invalid. We need to correct it. JSONLint can be helpful for that. I took your JSON and corrected the syntax errors until I got this:
{
"userId": 321,
"account": "new",
"fname": "Adam",
"lname": "Silver",
"features":[
{
"available": true,
"status": "open",
"admin": false
}
]
}
Then I need to generate a C# class structure to represent this JSON. I could manually create it, but the excellent json2csharp.com can generate it for me quickly. I fed this JSON into and received the following classes back:
public class Feature
{
public bool available { get; set; }
public string status { get; set; }
public bool admin { get; set; }
}
public class RootObject
{
public int userId { get; set; }
public string account { get; set; }
public string fname { get; set; }
public string lname { get; set; }
public List<Feature> features { get; set; }
}
I put these class definitions into my application. Then I need to modify my action method to create an instance of this RootObject class (you should change the name to actually match what it's intended for).
[HttpGet]
public ActionResult<RootObject> Get()
{
// Create an instance of our RootObject and set the properties
var myRootObject = new RootObject();
myRootObject.userId = 321;
myRootObject.account = "new";
myRootObject.fname = "Adam";
myRootObject.lname = "Silver";
myRootObject.features = new List<Feature>();
// Create an instance of a feature and set its properties
var feature = new Feature();
feature.available = true;
feature.status = "open";
feature.admin = false;
// Add the new feature to the features collection of our RootObject
myRootObject.features.Add(feature);
// Return the instance of our RootObject
// The framework will handle serializing it to JSON for us
return myRootObject;
}
Note that I changed the signature of your method. I made it no longer accept an IEnumerable because it wasn't clear why you had that. And I changed it to return an ActionResult after checking Microsoft's documentation.

Hi Please find correct JSON format for above one:
{
"userId": 321,
"account": "new",
"fname": "Adam",
"lname": "Silver",
"features": [{
"available": true,
"status": "open",
"admin": false
}]
}
you can use below class in your web API to pass respective data
public class Feature
{
public bool available { get; set; }
public string status { get; set; }
public bool admin { get; set; }
}
public class RootObject
{
public int userId { get; set; }
public string account { get; set; }
public string fname { get; set; }
public string lname { get; set; }
public List<Feature> features { get; set; }
}
then at the end, while returning data, convert the respective class object into JSON by serializing that into JSON format.
Hope it will fulfill your requirement.

Putting the comments into an answer:
If you are using ActionResult, I'll assume you are using asp.net mvc. What you want is JsonResult.
[HttpGet]
public JsonResult Get()
{
return new JsonResult
{
Data = new
{
userId = 321,
account = new
{
fname = "Adam",
lname = "Silver",
features = new object[]{
new
{
available = true,
status = "open",
admin = false
}
}
}
},
JsonRequestBehavior = JsonRequestBehavior.AllowGet
};
}

400 Bad Request submitting Json to WebApi via HttpClient.PutAsync

Normally, serialized objects would be used from the services to the webapi calls but in this instance I have to use a json representation for the call.
The process would be to deserialize the json to the proper class, then process as usual.
HttpClient Put
Method is called from within a console app
public async Task<ApiMessage<string>> PutAsync(Uri baseEndpoint, string relativePath, Dictionary<string, string> headerInfo, string json)
{
HttpClient httpClient = new HttpClient();
if (headerInfo != null)
{
foreach (KeyValuePair<string, string> _header in headerInfo)
_httpClient.DefaultRequestHeaders.Add(_header.Key, _header.Value);
}
httpClient.DefaultRequestHeaders.Accept.Clear();
httpClient.DefaultRequestHeaders.Accept.Add(
new MediaTypeWithQualityHeaderValue("application/json-patch+json"));
var content = new StringContent(json, Encoding.UTF8, "application/json-patch+json");
var response = await httpClient.PutAsync(CreateRequestUri(relativePath, baseEndpoint), content);
var data = await response.Content.ReadAsStringAsync();
...
}
Endpoint
The call never hits the endpoint. The endpoint is hit if I remove the [FromBody] tag but as expected, the parameter is null. There seems to be some sort of filtering happening.
[HttpPut()]
[Route("")]
[SwaggerResponse(StatusCodes.Status200OK)]
[SwaggerResponse(StatusCodes.Status400BadRequest)]
public async Task<IActionResult> UpdatePaymentSync([FromBody] string paymentSyncJson)
{
if (string.IsNullOrEmpty(paymentSyncJson))
return BadRequest();
//hack: don't have access to models so need to send json rep
var paymentSync = JsonConvert.DeserializeObject<PaymentSync>(paymentSyncJson);
....
}
This is the json payload. I thought [FromBody] took care of simple types but this is proving me wrong.
{
"paymentSyncJson": {
"id": 10002,
"fileName": "Empty_20190101.csv",
"comments": "Empty File",
"processingDate": "2019-01-02T19:43:11.373",
"status": "E",
"createdDate": "2019-01-02T19:43:11.373",
"createdBy": "DAME",
"modifiedDate": null,
"modifiedBy": null,
"paymentSyncDetails": []
}
}

Just expanding on my Comment.
The OP did:
[HttpPut()]
[Route("")]
[SwaggerResponse(StatusCodes.Status200OK)]
[SwaggerResponse(StatusCodes.Status400BadRequest)]
public async Task<IActionResult> UpdatePaymentSync([FromBody] string paymentSyncJson)
{
if (string.IsNullOrEmpty(paymentSyncJson))
return BadRequest();
//hack: don't have access to models so need to send json rep
var paymentSync = JsonConvert.DeserializeObject<PaymentSync>(paymentSyncJson);
....
}
Where they have put [FromBody] string paymentSyncJson, FromBody will try and deserialise into the type you specify, in this case string. I suggest doing:
public async Task<IActionResult> UpdatePaymentSync([FromBody] JObject paymentSyncJson)
Then you can change this line:
var paymentSync = JsonConvert.DeserializeObject<PaymentSync>(paymentSyncJson);
To:
var paymentSync = paymentSyncJson.ToObject<PaymentSync>();

Your payload is not a string, it's a json, that's why the runtime can't parse the body to your requested string paymentSyncJson.
To solve it, create a matching dto which reflects the json
public class PaymentDto
{
public PaymentSyncDto PaymentSyncJson { get; set; }
}
public class PaymentSyncDto
{
public int Id { get; set; }
public string FileName { get; set; }
public string Comments { get; set; }
public DateTime ProcessingDate { get; set; }
public string Status { get; set; }
public DateTime CreatedDate { get; set; }
public string CreatedBy { get; set; }
public DateTime ModifiedDate { get; set; }
public string ModifiedBy { get; set; }
public int[] PaymentSyncDetails { get; set; }
}
Then use it in the controller method to read the data from the request body
public async Task<IActionResult> UpdatePaymentSync([FromBody] PaymentDto payment)

NEST Api SearchAfter return null in NEST but works in Kibana

We are using elastic search just for document search in our application so we don't have any one expert in it. I was able to use TermQuery, SimpleQueryStringQuery and MatchPhraseQuery successfully. But I found out in documentation that using From & Size for pagination is not good for production and Search After is recommended.
But my implementation return null. It is confusing for me what should be in <Project> parameter as shown in Nest API Object Initializer Syntax in docs here.
My code looks like this:
var request = new SearchRequest<ElasticSearchJsonObject._Source>
{
//Sort = new List<ISort>
//{
// new SortField { Field = Field<ElasticSearchJsonObject>(p=>)}
//},
SearchAfter = new List<object> {
},
Size = 20,
Query = query
};
Reality is I don't understand this. Over here ElasticSearchJsonObject._Source is the class to map returned results.
My documents are simple text documents and I only want documents sorted according to score so document Id is not relevant.
There was already a question like this on SO but I can't find it somehow.
Update
After looking at answer I updated my code and though query obtained does work. It return result in kibana but not in NEST.
This is the new updated code:
var request = new SearchRequest<ElasticSearchJsonObject.Rootobject>
{
Sort = new List<ISort>
{
new SortField { Field = "_id", Order = SortOrder.Descending}
},
SearchAfter = new List<object> {
"0fc3ccb625f5d95b973ce1462b9f7"
},
Size = 1,
Query = query
};
Over here I am using size=1 just for test as well as hard code _id value in SearchAfter.
The query generated by NEST is:
{
"size": 1,
"sort": [
{
"_id": {
"order": "desc"
}
}
],
"search_after": [
"0fc3ccb625f5d95b973ce1462b9f7"
],
"query": {
"match": {
"content": {
"query": "lahore",
"fuzziness": "AUTO",
"prefix_length": 3,
"max_expansions": 10
}
}
}
}
The response from the ES does say successful but no results are returned.
Results do return in Kibana
Query status is successful
But...
Total returned is 0 in NEST
Sort value is null in kibana I used TrackScores = true to solve this issue
Here is the debug information:
Valid NEST response built from a successful low level call on POST: /extract/_source/_search?typed_keys=true
# Audit trail of this API call:
- [1] HealthyResponse: Node: http://localhost:9200/ Took: 00:00:00.1002662
# Request:
{"size":1,"sort":[{"_id":{"order":"desc"}}],"search_after":["0fc3ccb625f5d95b973ce1462b9f7"],"query":{"match":{"content":{"query":"lahore","fuzziness":"AUTO","prefix_length":3,"max_expansions":10}}}}
# Response:
{"took":3,"timed_out":false,"_shards":{"total":5,"successful":5,"skipped":0,"failed":0},"hits":{"total":0,"max_score":null,"hits":[]}}
So please tell me where I am wrong and what can be the problem and how to solve it.
Update 2:
Code in Controller:
Connection String:
var node = new Uri("http://localhost:9200");
var settings = new ConnectionSettings(node);
settings.DisableDirectStreaming();
settings.DefaultIndex("extract");
var client = new ElasticClient(settings);
Query:
var query = (dynamic)null;
query = new MatchQuery
{
Field = "content",
Query = content,
Fuzziness = Fuzziness.Auto,
PrefixLength = 3,
MaxExpansions = 10
};
Query Builder
var request = new SearchRequest<ElasticSearchJsonObject.Rootobject>
{
Sort = new List<ISort>
{
new SortField { Field = "_id", Order = SortOrder.Descending}
},
SearchAfter = new List<object> {
documentid //sent as parameter
},
Size = 1, //for testing 1 other wise 10
TrackScores = true,
Query = query
};
JSON Query
I use this code to get query I posted above. This query is then passed to kibana with GET <my index name>/_Search and there it works
var stream = new System.IO.MemoryStream();
client.SourceSerializer.Serialize(request, stream);
var jsonQuery = System.Text.Encoding.UTF8.GetString(stream.ToArray());
ES Response
string responseJson = "";
ElasticSearchJsonObject.Rootobject response = new ElasticSearchJsonObject.Rootobject();
var res = client.Search<object>(request);
if (res.ApiCall.ResponseBodyInBytes != null)
{
responseJson = System.Text.Encoding.UTF8.GetString(res.ApiCall.ResponseBodyInBytes);
try
{
response = JsonConvert.DeserializeObject<ElasticSearchJsonObject.Rootobject>(responseJson);
}
catch (Exception)
{
var model1 = new LoginSignUpViewModel();
return PartialView("_NoResultPage", model1);
}
}
This is where things go wrong. Above debug information was captured from response
ElasticSearchJsonObject
Some how I think problem might be here somewhere? The class is generated by taking response from NEST in Search request.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace ESAPI
{
public class ElasticSearchJsonObject
{
public class Rootobject
{
public int took { get; set; }
public bool timed_out { get; set; }
public _Shards _shards { get; set; }
public Hits hits { get; set; }
}
public class _Shards
{
public int total { get; set; }
public int successful { get; set; }
public int skipped { get; set; }
public int failed { get; set; }
}
public class Hits
{
public int total { get; set; }
public float max_score { get; set; }
public Hit[] hits { get; set; }
}
public class Hit
{
public string _index { get; set; }
public string _type { get; set; }
public string _id { get; set; }
public float _score { get; set; }
public _Source _source { get; set; }
}
public class _Source
{
public string content { get; set; }
public Meta meta { get; set; }
public File file { get; set; }
public Path path { get; set; }
}
public class Meta
{
public string title { get; set; }
public Raw raw { get; set; }
}
public class Raw
{
public string XParsedBy { get; set; }
public string Originator { get; set; }
public string dctitle { get; set; }
public string ContentEncoding { get; set; }
public string ContentTypeHint { get; set; }
public string resourceName { get; set; }
public string ProgId { get; set; }
public string title { get; set; }
public string ContentType { get; set; }
public string Generator { get; set; }
}
public class File
{
public string extension { get; set; }
public string content_type { get; set; }
public DateTime last_modified { get; set; }
public DateTime indexing_date { get; set; }
public int filesize { get; set; }
public string filename { get; set; }
public string url { get; set; }
}
public class Path
{
public string root { get; set; }
public string _virtual { get; set; }
public string real { get; set; }
}
}
}
I am sure this can be used to get response.
Please note that in case of simple search this code works:
so for this query below my code is working:
var request = new SearchRequest
{
From = 0,
Size = 20,
Query = query
};

Using from/size is not recommended for deep pagination because of the amount of documents that need to be fetched from all shards for a deep page, only to be discarded when finally returning an overall ordered result set. This operation is inherent to the distributed nature of Elasticsearch, and is common to many distributed systems in relation to deep pagination.
With search_after, you can paginate forward through documents in a stateless fashion and it requires
the documents returned from the first search response are sorted (documents are sorted by _score by default)
passing the values for the sort fields of the last document in the hits from one search request as the values for "search_after": [] for the next request.
In the Search After Usage documentation, a search request is made with sort on NumberOfCommits descending, then by Name descending. The values to use for each of these sort fields are passed in SearchAfter(...) and are the values of Project.First.NumberOfCommits and Project.First.Name properties, respectively. This tells Elasticsearch to return documents that have values for the sort fields that correspond to the sort constraints for each field, and relate to the values supplied in the request. For example, sort descending on NumberOfCommits with a supplied value of 775 means that Elasticsearch should only consider documents with a value less than 775 (and to do this for all sort fields and supplied values).
If you ever need to dig further into any NEST documentation, click the "EDIT" link on the page:
which will take you to the github repository of the documentation, with the original asciidoc markdown for the page:
Within that page will be a link back to the original NEST source code from which the asciidoc was generated. In this case, the original file is SearchAfterUsageTests.cs in the 6.x branch