Use Telerik Reporting REST Service API with C Sharp HttpClient

Environment

Product	Progress® Telerik® Reporting
Preferred Language	C Sharp

Description

Sometimes it is sufficient to generate and download reports in certain formats without displaying them in a viewer.

Solution

You may create a custom HttpClient that performs the necessary requests to the Reporting REST Service to get the desired reports. Attached is a sample solution demonstrating how to use Telerik Reporting REST Service with a simple C# HttpClient. The solution includes the REST Service (RestService1 project) and the client in a separate Console application (ConsoleApplication2 project). The application exports the report in PDF format in c:\temp folder. The sample report uses the sample AdventureWorks database. To run the report successfully it is required to have the database installed and to modify the named connection string in the Web.config file of the RestService1 project according to your local settings.

CSharpRestServiceClient.zip

The code of the HttpClient :

public class ReportClient : IDisposable
    {
        public string BaseAddress { get; set; }
        public HttpClient client;
        public string ClientId;

        public ReportClient(string uri)
        {
            this.client = new HttpClient();
            this.BaseAddress = uri;

            this.client.BaseAddress = new Uri(this.BaseAddress);
        }

        public void Dispose()
        {
            using (this.client) { }
        }

        public void RegisterClient()
        {
            var headers = new List<KeyValuePair<string, string>>();
            var content = new FormUrlEncodedContent(headers);

            var registerClientTask = this.client.PostAsync(this.BaseAddress + "/clients", content);
            var response = registerClientTask.Result;

            if (response.IsSuccessStatusCode)
            {
                var clientIdTask = response.Content.ReadAsAsync<ClientIDModel>();
                var clientId = clientIdTask.Result;
                this.ClientId = clientId.ClientId;
            }
            else
            {
                var error = response.Content.ReadAsAsync<ErrorModel>().Result;
                throw new Exception(error.Description);
            }
        }

        public string CreateInstance(string reportSource)
        {
            HttpContent content = new StringContent(reportSource, Encoding.UTF8, "application/json");

            string route = $"{this.BaseAddress}/clients/{this.ClientId}/instances";
            var instanceTask = this.client.PostAsync(route, content);

            InstanceIdModel instanceId = null;
            var response = instanceTask.Result;
            if (response.IsSuccessStatusCode)
            {
                instanceId = response.Content.ReadAsAsync<InstanceIdModel>().Result;
            }
            else
            {
                var error = response.Content.ReadAsAsync<ErrorModel>().Result;
                throw new Exception(error.Description);
            }

            return instanceId.InstanceId;
        }

        public string CreateDocument(string instanceId, string format, string deviceInfo = null, string useCache = "true")
        {
            string contentBody = $"{{ \"useCache\": {useCache}, \"format\": \"{format}\" }}";
            HttpContent content = new StringContent(contentBody, Encoding.UTF8, "application/json");

            string route = $"{this.BaseAddress}/clients/{this.ClientId}/instances/{instanceId}/documents";
            var documentTask = this.client.PostAsync(route, content);

            DocumentIdModel documentId = null;
            var response = documentTask.Result;
            if (response.IsSuccessStatusCode)
            {
                documentId = response.Content.ReadAsAsync<DocumentIdModel>().Result;
            }
            else
            {
                var error = response.Content.ReadAsAsync<ErrorModel>().Result;
                throw new Exception(error.Description);
            }

            return documentId.DocumentId;
        }

        public bool DocumentIsProcessing(string instanceId, string documentId)
        {
            string route = $"{this.BaseAddress}/clients/{this.ClientId}/instances/{instanceId}/documents/{documentId}/Info";

            var documentInfoTask = this.client.GetAsync(route);

            DocumentInfoModel documentInfo = null;
            var response = documentInfoTask.Result;
            if (response.IsSuccessStatusCode)
            {
                documentInfo = response.Content.ReadAsAsync<DocumentInfoModel>().Result;
            }
            else
            {
                var error = response.Content.ReadAsAsync<ErrorModel>().Result;
                throw new Exception(error.Description);
            }

            return !documentInfo.DocumentReady;
        }

        public byte[] GetDocument(string instanceId, string documentId)
        {
            string route = $"{this.BaseAddress}/clients/{this.ClientId}/instances/{instanceId}/documents/{documentId}";

            var getDocumentTask = this.client.GetAsync(route);

            byte[] documentBytes = null;
            var response = getDocumentTask.Result;
            if (response.IsSuccessStatusCode)
            {
                documentBytes = response.Content.ReadAsByteArrayAsync().Result;
            }
            else
            {
                var error = response.Content.ReadAsAsync<ErrorModel>().Result;
                throw new Exception(error.Description);
            }

            return documentBytes;
        }

        private static void EnsureSuccessStatusCode(HttpResponseMessage response)
        {
            if (!response.IsSuccessStatusCode)
            {
                throw
                    new Exception(
                        response.ReasonPhrase +
                        Environment.NewLine +
                        response.RequestMessage.RequestUri);
            }
        }
    }    

Here are also the Models used :

    public class ClientIDModel
    {
        [JsonProperty("clientId")]
        public string ClientId { get; set; }
    }

    public class ReportSourceModel
    {
        [JsonProperty("Report")]
        public string Report { get; set; }
        [JsonProperty("ParameterValues")]
        public IDictionary<string, object> ParameterValues { get; set; }
    }

    public class InstanceIdModel
    {
        [JsonProperty("instanceId")]
        public string InstanceId { get; set; }
    }

    public class DocumentIdModel
    {
        [JsonProperty("documentId")]
        public string DocumentId { get; set; }
    }

    public class DocumentInfoModel
    {
        [JsonProperty("documentReady")]
        public bool DocumentReady { get; set; }

        [JsonProperty("PageCount")]
        public int PageCount { get; set; }

        [JsonProperty("DocumentMapAvailable")]
        public bool DocumentMapAvailable { get; set; }
    }

    public class ErrorModel
    {
        [JsonProperty("error")]
        public string Error { get; set; }

        [JsonProperty("error_description")]
        public string Description { get; set; }
    }