REST Client for ServiceNow's TableAPI for GET call in C#

[Satish Babu]

 Hello there, 

Working with the Web Developer in integrating our ServiceNow platform with there WebApp.

As part of the development, we need a batch job that would query a list of records from the ServiceNow table and update curtains values in there WebApp.

But we unable to query the list of records using SNOW Table API for a specific date.

Can you someone help us with the C# code to get a list of records from a table for a specific date or a date range.

C# code the Web Developer has written.

var client = new RestClient(Instanceurl+ "/api/now/table/incident?sysparm_limit=15");

client.Authenticator = new HttpBasicAuthenticator(user, password);

var request = new RestRequest("incident", Method.GET);

request.AddParameter("sys_updated_on", "2020-02-18 19:23:22");

//Works but only when I pass the specific DateTime value.

request.RequestFormat = DataFormat.Json;

IRestResponse response = client.Execute(request);

dynamic _result = JsonConvert.DeserializeObject<RestAPIResult.ChildrenRootObject>(response.Content.ToString());

if (_result.result.Count > 0) //Important to prevent "Object reference not set to an instance of an object" error.

{

[Harsh Vardhan]

i think in C# you can pass the below line to get the date time and then pass it. 

DateTime now = DateTime.Now;

i think this way it should work. also add log to check the now value .

request.AddParameter("sys_updated_on", now);

[Simon Christens · Accepted solution]

Hi Satish

I have been like 15 years since i worked with C# but it should be possible to you duo to ServiceNow's input.

I would suggest that you use ServiceNows query builder to make you initial queries and then build them in your C# app

These are examples for different inputs for ServiceNow to filter in either periods or "today" as examples

query["sysparm_query"] = "sys_updated_onBETWEENjavascript:gs.dateGenerate('2020-03-01','00:00:00')@javascript:gs.dateGenerate('2020-05-17','00:00:00')";
query["sysparm_query"] = "sys_updated_on>=javascript:gs.beginningOfToday()";

And then:

Below is a C# sample that should return the correct incidents from a given period or date of these examples

using System;
using System.Net.Http;
using System.Text;
using System.Web;
using System.Collections.Generic;

namespace cs_test
{
    internal class Program
    {
        internal static void Main(string[] args)
        {
            byte[] byteArray = Encoding.ASCII.GetBytes("username:password");

            UriBuilder builder = new UriBuilder("https://instance.service-now.com/api/now/table/incident");

            var query = HttpUtility.ParseQueryString(builder.Query);
            query["sysparm_limit"] = "15";
            query["sysparm_fields"] = "number,short_description";
            query["sysparm_query"] = "sys_updated_onBETWEENjavascript:gs.dateGenerate('2020-03-01','00:00:00')@javascript:gs.dateGenerate('2020-05-17','00:00:00')";
            //query["sysparm_query"] = "sys_updated_on>=javascript:gs.beginningOfToday()";
            builder.Query = query.ToString();
            string url = builder.ToString();
            
            Console.WriteLine(url);

            GetRequst(url, byteArray);

            Console.ReadKey();
        }

        async static void GetRequst(string url, byte[] byteArray){

            using (HttpClient client = new HttpClient()){

                client.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Basic", Convert.ToBase64String(byteArray));
                

                using (HttpResponseMessage response = await client.GetAsync(url)){

                    using(HttpContent content = response.Content){

                        string myContent = await content.ReadAsStringAsync();
                        var records = Newtonsoft.Json.JsonConvert.DeserializeObject<RootObject>(myContent);
   
                        Console.WriteLine(records.result.Count);

                        foreach(Record rec in records.result){

                            Console.WriteLine(rec.number + " - " + rec.short_description);
                        }        

                    }
                }
            }
        }
    }
    internal class RootObject{
        public List<Record> result { get; set; }
    }

    internal class Record{

        public string number { get; set; }
        public string short_description { get; set; }

    }
}

[Satish Babu]

Awesome!! worked like a champ.

Thanks, Simon

[Sema A]

Simon, your solution worked. Thank you so much for sharing this information