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gRPC: How to use dynamically typed values?

I'm trying using gRPC dynamically typed values but with the little information about their usefulness, It's almost impossible to do this... So I will show the image/code that I have problems and the questions that are eating my brain
gRPC Method I'm doing:
public override Task<HelloReply2> TestObject(Status request, ServerCallContext context) {
//The part I may have problems
var status = new Status();
//here I want a User that corresponds to my request.Data
//example -> request.Data = User1 (gives me null if User1 don`t exist in db)
// request.Data = 14 (gives me null if 14 don`t exist in db)
// request.Data = true (gives me null if true don`t exist in db)
var a1 = _context.Users_5.FirstOrDefault(x => x.Username.Equals(request.Data));
var b1 = _context.Users_5.FirstOrDefault(x => x.Email.Equals(request.Data));
var c1 = _context.Users_5.FirstOrDefault(x => x.Age.Equals(request.Data));
var d1 = _context.Users_5.FirstOrDefault(x => x.Test.Equals(request.Data));
//is a bool
//here i want too Create dynamic values
status.Data = Value.ForStruct(new Struct {
Fields =
{
["Integer"] = Value.ForNumber(c1!.Age),
["StringName"] = Value.ForString(a1!.Username),
["StringEmail"] = Value.ForString(b1!.Email),
["Boolean"] = Value.ForBool(d1!.Test)
}
});
//Below is just a simple string who gives different string (depending on the
//data Status (also how to read the message from the status.Data ?)
HelloReply2 hello = new();
if(a1 != null)
{
hello.Message = "There is a User with the Username " + request.Data + ". His Email is " + a1.Email;
} else if (b1 != null) {
hello.Message = "There is a User with the Email " + request.Data + ". His Username is " + b1.Username;
}
else if (c1 != null)
{
hello.Message = "There is at least one User with that Age of " + request.Data + ". His Username is " + c1.Username;
}
else if (d1 != null)
{
if(d1.Test == true)
{
hello.Message = "There is at least one User who dislikes chocolate: " + request.Data + ". His Username is " + d1.Username;
} else
{
hello.Message = hello.Message = "There is at least one User who likes chocolate: " + request.Data + ". His Username is " + d1.Username;
}
}
else
{
hello.Message = "We didn't find something with the value that the User put in. Value:" + request.Data;
}
return Task.FromResult(hello);
}
Questions: How to Get the one Value from my gRPC? How to convert a "Object" in c# (one string, one integer or one List) into a ONE value of google.protobuf.Value (so it not give me errors like this Controller from a Web Api below)? Is something wrong with my gRPC Service Method (is something wrong reading the dynamic values? Can I do that calls for getting a User for a DB? How to read dynamic values?)
// I try using Google.Protobuf.WellKnownTypes.Value obj but
//not workings because gives me a lot of values to put
[HttpGet("TypeObject/{obj}")]
public async Task<ActionResult<HelloReply2>> TypeObject([FromRoute] Object obj){
Status objRequest = new Status { Data = (Google.Protobuf.WellKnownTypes.Value)
obj };
//cannot do this (gives me error of casting but the ideia is doing something
//similar to this)
var hello = await _greetClient.TestObjectAsync(objRequest);
return Ok(hello);
}
Any help on how to resolve this error of using Value gRPC or if is something wrong with the code is always welcome.
Edit:
One day after this question I don't have any solutions / progress. I was think of doing Any or OneOf for testing but it also gives me errors (who don't make sense at all). This code from Microsoft (C# Format part is not recognize) doesn't work in my project with the protos reload (the problem is not in the protos)
Link: https://learn.microsoft.com/en-us/dotnet/architecture/grpc-for-wcf-developers/protobuf-any-oneof
How I can use Any / OneOf without give me error in the Formating? What is the difference between Value and this two? Can the three (Value, Any, OneOf) be dynamic/Object values (if yes how to convert the types)?
Edit 2:
Still have problems, I'm trying using gRPC Any , and maybe have some progress (not all).
So with Any I have my method in the server gRPC and it is like this
public override Task<HelloReply2> TestObject3(AnyMessage request, ServerCallContext context){
HelloReply2 anyMessageResponse;
var y = request.TypeUrl;
switch (request.TypeUrl)
{
case "type.googleapis.com/any.HelloRequest":
var string_1 = request.Unpack<HelloRequest>();
anyMessageResponse = new HelloReply2{
Message = "You type String: " + $"{string_1.Name}"
};
break;
case "type.googleapis.com/any.TestInteger1":
var integer_1 = request.Unpack<TestInteger1>();
anyMessageResponse = new HelloReply2{
Message = "You type Integer: " + $"{integer_1.Message}"
};
break;
case "type.googleapis.com/any.TestBool1":
var bool_1 = request.Unpack<TestInteger1>();
anyMessageResponse = new HelloReply2{
Message = "You type Bool: " + $"{bool_1.Message}"
};
break;
default:
throw new InvalidOperationException("Unexpected type URL.");}
return Task.FromResult(anyMessageResponse);
}
This ideia comes from here (https://github.com/grpc/grpc-dotnet/issues/917), but the client part their don't have any much info or I don't understand that part
This is what I did in the WebApi (who is my client and the code is similar to the above one)
using AnyMessage = Google.Protobuf.WellKnownTypes.Any;
[HttpGet("TypeObject3/{obj3}")]
public async Task<ActionResult<HelloReply2>> TypeObject3([FromRoute] string obj3)
{
AnyMessage objRequest = new() { TypeUrl = obj3 };
var hello = await _greetClient.TestObject3Async(objRequest);
var l = hello.Message;
return Ok(hello);
}
First I had the variable Any declared in the method instead of string but as you can only put string and stringBytes so I preferred to put it like this (with the string as an obj3 variable) but my goal is to see if the variable is of type TestBool1 or TestInteger1 as I have declared in the protos and not be a string that I will be able to see, and the biggest problem was if I had more variables inside the messages how to proceed? So my secondary question is how to use Any on the client side via the Web-Api? I forgot to say but I'm using .Net 6 Core and for testing I'm using Swagger, where at this moment my error hits the Exception dictated by the Server method.
Questions: Why TypeUrl is a string and not object? How to fix my problem? How to test the object type (or string) for more values if the messages was with 1 more types?
Also I will show my test proto too show how I'm doing this
import "google/protobuf/struct.proto";
import "google/protobuf/any.proto";
package greet;
// The greeting service definition.
service Greeter {
// Sends a greeting
rpc SayNormalHello (Empty_2) returns (HelloReply);
rpc SayHello (HelloRequest) returns (HelloReply2);
rpc TestInt (TestInteger1) returns (HelloReply2);
rpc TestBoolean (TestBool1) returns (HelloReply2);
rpc TestObject (Status) returns (HelloReply2); //Not working
rpc TestObject2 (Status2) returns (HelloReply2); //Not working
rpc TestObject3 (google.protobuf.Any) returns (HelloReply2); //Also
//Not working
}
message Empty_2{
}
// The request message containing the user's name.
message HelloRequest {
string name = 1;
}
// The response message containing the greetings.
message HelloReply {
string message = 1;
}
// The response message containing the greetings.
message HelloReply2 {
string message = 1;
}
message TestInteger1 {
int32 message = 1;
}
message TestBool1 {
bool message = 1;
}
message Status {
google.protobuf.Value data = 1;
}
message Status2 {
google.protobuf.Any data = 1;
}
Any help is welcome.

In the project I developed, I needed an infrastructure where I could perform dynamic operations such as REST service using gRPC. As I understand it, what you want is something similar to this.
I have developed a solution for this. It might work for you too.
You can gain some flexibility by making a definition with a single String field for Requests and Responses that you want to be Dynamic, and then using this field to hold JSON data as strings.
For example, instead of defining different responses for different types, you can solve it by making one definition like this.
message HelloReply {
// Stringified JSON Data
string data = 1;
}

How do I post XML to an API using ASP.NET Core 5?

I'm creating an application which talks to an external API, the external API only accepts XML posts for dealing with information. I've written most of it and I'm at a point where I need to feed the XML information which includes the DTD to the API and I cannot get it to work.
CarApiService
This is where I'm struggling, I have the required XML which I need to post and so I thought I would used the XmlDocument to load it, then, rather than using PostAsync I could use PostAsXmlAsync which is more appropriate.
public async Task<string> RequestParts(string partNumber = "0")
{
//Store any errors as a string
string errors;
//LoadXML
XmlDocument document = new();
document.LoadXml("<?xml version='1.0' encoding='UTF-8'?><!DOCTYPE gmPartsRequest PUBLIC '-//GeneralMotors//DTD GmPartsRequest v1//EN' 'http://dtd.generalmotors.com/parts_request_version1.dtd'>" +
"<partsService version='1.4' dealershipId='xxx'></partsService>");
//Create HttpClient
var client = _clientFactory.CreateClient("external");
try
{
var postData = await client.PostAsXmlAsync(client.BaseAddress, document);
errors = null;
return something.ToString();
}
catch (Exception ex)
{
errorString = $"There was an error getting your parts data: { ex.Message }";
return errors;
}
}
There are a few things that bother me about my above code and I'm hoping someone can help:
PostAsXmlAsync returns an error when it executes and I'm not sure how to resolve it:
There was an error getting your parts data: Type
'System.Xml.XmlElement' with data contract name
'XmlElement:http://schemas.datacontract.org/2004/07/System.Xml' is not
expected. Add any types not known statically to the list of known
types - for example, by using the KnownTypeAttribute attribute or by
adding them to the list of known types passed to
DataContractSerializer.
Given that I store the API information in the startup file, is there any way to avoid having to supply the PostAsXmlAsync with the base address in this way?
Should this really be returning as a string given that I'm supposed to be posting and receiving XML?

How to read json file in asp.net web api

In my asp.web api 2.0 project I have a Json file, where all the error codes are mapped. I want to read the json file in order to return response to the caller.
I am unable to read the same, however if I use console application following code works, any suggestion will be helpful.
Code that works in console application:
var assembly = Assembly.GetExecutingAssembly();
using (var stream = new StreamReader(assembly.GetManifestResourceStream("ConsoleApp24.Utilities.StatusCodes.json") ?? throw new InvalidOperationException()))
{
var status = JsonConvert.DeserializeObject<RootObject>(stream.ReadToEnd());
}
Using above code provides assembly as null in web api project, hence I changed it to following:
var assembly = GetWebEntryAssembly();
using (var stream = new StreamReader(assembly.GetManifestResourceStream("PaymentAccount.Api.Resources.StatusCodes.json") ?? throw new InvalidOperationException()))
{
var status = JsonConvert.DeserializeObject<RootObject>(stream.ReadToEnd());
}
private Assembly GetWebEntryAssembly()
{
if (System.Web.HttpContext.Current == null ||
System.Web.HttpContext.Current.ApplicationInstance == null)
{
return null;
}
var type = System.Web.HttpContext.Current.ApplicationInstance.GetType();
while (type != null && type.Namespace == "ASP")
{
type = type.BaseType;
}
return type == null ? null : type.Assembly;
}
The exception I get is:
Operation is not valid due to the current state of the object.

With Server.MapPath it is easy for ASP.NET to find your files but the file still have to be inside of the application root folder, here is some official documentation on this function.
Just place file inside your root folder, and then use Server.MapPath this will allow your ASP.NET application to find your file in the Server file system.
string json = File.ReadAllText(Server.MapPath("~/files/myfile.json"));

You can try this :
public object Get()
{
string allText = System.IO.File.ReadAllText(#"c:\data.json");
object jsonObject = JsonConvert.DeserializeObject(allText);
return jsonObject;
}
this code returns json text

How to check whether a facebook user liked my facebook page or not using ASP.Net

I want to check whether a facebook user liked my facebook page or not. I got so many solutions using javascript but I want to implement this requirement in ASP.Net.
I copied the code from the below link:
http://duanedawnrae.com/Blog/post/2012/02/29/Determine-if-a-Facebook-user-Likes-your-page-with-ASPNET.aspx
I got the below ASP.Net code which works for the same.
ASP.Net code:
public class WebService : System.Web.Services.WebService
{
[WebMethod()]
public string GetFacebookLikeStatus(string fbpageid, string fbappid, string fbtoken, string fburl)
{
string strReturn = null;
// Placeholder for the Facbook "like" API call
string strURL = null;
strURL = "https://graph.facebook.com/me/likes?access_token=" + fbtoken;
// Placeholder for the Facebook GET response
WebRequest objGETURL = null;
objGETURL = WebRequest.Create(strURL);
// Declare response stream
Stream objStream = null;
// Declare The Facebook response
string strLine = null;
// Declare a count on the search term
int intStr = 0;
try
{
// Create an instance of the StreamReader
StreamReader objReader = new StreamReader(objStream);
// Get the response from the Facebook API as a JSON string.
// If access_token is not correct for the logged
// on user Facebook returns (400) bad request error
objStream = objGETURL.GetResponse().GetResponseStream();
// If all is well
try
{
// Execute the StreamReader
strLine = objReader.ReadToEnd().ToString();
// Check if Facebook page Id exists or not
intStr = strLine.IndexOf(fbpageid); // if valid return a value
if (intStr > 0)
{
strReturn = "1";
// if not valid return a value
}
else
{
strReturn = "0";
}
objStream.Dispose();
}
catch (Exception ex)
{
// For testing comment out for production
strReturn = ex.ToString();
// Uncomment below for production
//strReturn = "Some friendly error message"
}
}
catch (Exception ex)
{
// For testing comment out for production
strReturn = ex.ToString();
// Uncomment below for production
//strReturn = "Some friendly error message"
}
return strReturn;
}
}
The above code contains a webservice which contains a single function. The function contains four input parameters and returns a single output string.
But when I run this webservice I got the error, “Value cannot be null. Parameter name: stream”. This error is coming because the “objStream” variable is set to null. Please fix the issue so that I can get my correct output as I dont know how to implement my requirement.

Like Gating is not allowed on Facebook, and neither is incentivizing users to like your Page. Users must like something only because they really want to, you can´t reward them in any way.
That being said, you would need the user_likes permission to use /me/likes, and you would need to get it approved by Facebook. Which will not happen just for checking if the user liked your Page.
Btw, that article is from 2012. A lot of stuff changed since then.

How do I open XML from link in razor?

The task is quite simple, connect to another webservice using XML.
In the current pages (classic ASP) we use the following code:
zoekpcode=UCASE(Request.Querystring("zoekpcode")) <-- postal-code
zoeknr=Request.Querystring("zoeknr") <-- house-number
PC=Trim(Replace(zoekpcode," ",""))
NR=Trim(Replace(zoeknr," ",""))
strGetAddress="https://ws1.webservices.nl/rpc/get-simplexml/addressReeksPostcodeSearch/*~*/*~*/" & PC & NR
set xml = Server.CreateObject("Microsoft.XMLHTTP")
xml.open "GET", strGetAddress , false
xml.send ""
strStatus = xml.Status
If Len(PC)>5 and Len(NR)>0 Then
strRetval = Trim(xml.responseText)
End If
set xml = nothing
'Do something with the result string
One of the possible links could be: https://ws1.webservices.nl/rpc/get-simplexml/addressReeksPostcodeSearch/~/~/1097ZD49
Currently I'm looking for a way to do this in razor (C#), but all I seem to be able to find on Google is how to do it in JavaScript
I've tried (most combinations of) the following terms:
razor
xmlhttp
comobject
XML from url
-javascript
Results were mostly about JavaScript or razorblades.
Based on other result (like in the search comobjects in razor) it seems that comobject aren't available in Razor.
I did find this question (How to use XML with WebMatrix razor (C#)) on stackoverflow that seems to answer my question (partially), but is it also possible with a link to an external system (the mentioned web-service)?

I have covered the consumption of Web Services in Razor web pages here: http://www.mikesdotnetting.com/Article/209/Consuming-Feeds-And-Web-Services-In-Razor-Web-Pages.
If your web service is a SOAP one, you are best off using Visual Studio (the free Express editions is fine) to add a service reference and then work from there. Otherwise you can use Linq To XML to load the XML directly into an XDocument as in the ATOM example in the article:
var xml = XDoxument.Load("https://ws1.webservices.nl/rpc/get-simplexml/blah/blah");
Then use the System.Xml.Linq APIs to query the document.

With the help of Ralf I came to the following code:
public static XmlDocument getaddress(string pcode, string number){
string serverresponse = "";
string getlocation = "https://ws1.webservices.nl/rpc/get-simplexml/addressReeksPostcodeSearch/*~*/*~*/" + Request.QueryString["PCODE"] + Request.QueryString["NR"];
HttpWebRequest req = (HttpWebRequest) WebRequest.Create(getlocation);
using (var r = req.GetResponse()) {
using (var s = new StreamReader(r.GetResponseStream())) {
serverresponse = s.ReadToEnd();
}
}
XmlDocument loader = new XmlDocument();
loader.LoadXml(serverresponse);
return loader;
}
public static string getvalue(XmlDocument document, string node){
string returnval = "";
var results = document.SelectNodes(node);
foreach(XmlNode aNode in results){
returnval = returnval + "," + aNode.InnerText;
}
return returnval.Substring(1);
}