Working with bpm'online objects over the OData protocol using Http request

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Xml;
using System.Xml.Linq; 

// String of address bpm’online OData servise.
private const string serverUri = "http://<server_name>/<BPMonline application_name>/0/ServiceModel/EntityDataService.svc/";
private const string authServiceUtri = "http://<server_name>/<BPMonline application_name>/ServiceModel/AuthService.svc/Login";

// Links to XML name spaces.
private static readonly XNamespace ds = "http://schemas.microsoft.com/ado/2007/08/dataservices";
private static readonly XNamespace dsmd = "http://schemas.microsoft.com/ado/2007/08/dataservices/metadata";
private static readonly XNamespace atom = "http://www.w3.org/2005/Atom"; 

// Request string
// GET <BPMonline application address>/0/ServiceModel/EntityDataService.svc/ContactCollection?$select=Id,Name

public static void GetOdataCollectionByAuthByHttpExample(string userName, string userPassword)
{
    // Creating an authentication request.
    var authRequest = HttpWebRequest.Create(authServiceUtri) as HttpWebRequest;
    authRequest.Method = "POST";
    authRequest.ContentType = "application/json";
    var bpmCookieContainer = new CookieContainer();
    // Including the cookie use into the request.
    authRequest.CookieContainer = bpmCookieContainer;
    // Receiving a stream associated with the authentication request.
    using (var requestStream = authRequest.GetRequestStream())
    {
        // Recording the BPMonline user accounts and additional request parameters into the stream.
        using (var writer = new StreamWriter(requestStream))
        {
            writer.Write(@"{
                                ""UserName"":""" + userName + @""",
                                ""UserPassword"":""" + userPassword + @""",
                                ""SolutionName"":""TSBpm"",
                                ""TimeZoneOffset"":-120,
                                ""Language"":""En-us""
                                }");
        }
    }
    // Receiving an answer from the server. If the authentication is successful, cookies will placed in the
    // bpmCookieContainer object and they may be used for further requests.
    using (var response = (HttpWebResponse)authRequest.GetResponse())
    {
        // Creating a request for data reception from the OData service.
        var dataRequest = HttpWebRequest.Create(serverUri + "ContactCollection?$select=Id, Name")
                                as HttpWebRequest;
        // The HTTP method GET is used to receive data.
        dataRequest.Method = "GET";
        // Adding pre-received authentication cookie to the data receipt request.
        dataRequest.CookieContainer = bpmCookieContainer;
        // Receiving a response from the server.
        using (var dataResponse = (HttpWebResponse)dataRequest.GetResponse())
        {
            // Uploading the server response to an xml-document for further processing.
            XDocument xmlDoc = XDocument.Load(dataResponse.GetResponseStream());
            // Receiving the collection of contact objects that comply with the request condition.
            var contacts = from entry in xmlDoc.Descendants(atom + "entry")
                           select new
                               {
                                   Id = new Guid(entry.Element(atom + "content")
                                                      .Element(dsmd + "properties")
                                                      .Element(ds + "Id").Value),
                                   Name = entry.Element(atom + "content")
                                               .Element(dsmd + "properties")
                                               .Element(ds + "Name").Value
                               };
            foreach (var contact in contacts)
            {
                // Implementing actions with contacts.
            }
        }
    } 

string requestUri = serverUri + "ContactCollection?$top=60";

string requestUri = serverUri + "ContactCollection?$skip=10";

string requestUri = serverUri + "ContactCollection?$orderby=Name";

string requestUri = serverUri + "ContactCollection?$top=4&$skip=1&$orderby=City/Name";

// Request string:
// GET <BPMonline application address>/0/ServiceModel/EntityDataService.svc/ContactCollection(guid'00000000-0000-0000-0000-000000000000')

public static void GetOdataObjectByIdExample()
{
    // Id of the sought object.
    string contactId = "00000000-0000-0000-0000-000000000000";

    // Forming a string of the request to the service.
    string requestUri = serverUri + "ContactCollection(guid'" + contactId + "')";

    // Creating an object of the request to the service.
    var request = HttpWebRequest.Create(requestUri) as HttpWebRequest;
    request.Method = "GET";
    request.Credentials = new NetworkCredential("BPMUserName", "BPMUserPassword");
    using (var response = request.GetResponse())
    {
        // Receiving a response from the service in the xml format.
        XDocument xmlDoc = XDocument.Load(response.GetResponseStream());
        // Receiving the contact objects collection satsifying the request condition.
        var contacts = from entry in xmlDoc.Descendants(atom + "entry")
                       select new
                           {
                               Id = new Guid(entry.Element(atom + "content")
                                                 .Element(dsmd + "properties")
                                                 .Element(ds + "Id").Value),
                               Name = entry.Element(atom + "content")
                                           .Element(dsmd + "properties")
                                           .Element(ds + "Name").Value
                               // Initiating the object properties required for further use.
                           };
        foreach (var contact in contacts)
        {
            // Implementing actions over the contact.
        }
    }
} 

// Request string:
// GET <BPMonline application address>/0/ServiceModel/EntityDataService.svc/ContactCollection?$filter=Id eq guid'00000000-0000-0000-0000-000000000000'

public static void GetOdataObjectByFilterConditionExample()
{
    // Id of the sought object.
    string contactId = "00000000-0000-0000-0000-000000000000";
    // Forming a string of the request to the service.
    string requestUri = serverUri + "ContactCollection?$filter = Id eq guid'" + contactId + "'";
    // Creating an object of the request to the service.
    var request = HttpWebRequest.Create(requestUri) as HttpWebRequest;
    request.Method = "GET";
    request.Credentials = new NetworkCredential("BPMUserName", "BPMUserPassword");
    using (var response = request.GetResponse())
    {
        // Receiving a response from the service in the xml format.
        XDocument xmlDoc = XDocument.Load(response.GetResponseStream());
        // Receiving the contact objects collection satisfying the request condition.
        var contacts = from entry in xmlDoc.Descendants(atom + "entry")
                       select new
                       {
                           Id = new Guid(entry.Element(atom + "content")
                                             .Element(dsmd + "properties")
                                             .Element(ds + "Id").Value),
                           Name = entry.Element(atom + "content")
                                       .Element(dsmd + "properties")
                                       .Element(ds + "Name").Value
                           // Initiating the object properties required for further use.
                       };
        foreach (var contact in contacts)
        {
           // Implementing actions over the contact.
        }
    }
} 

// Request string:
// GET <BPMonline applicationn address>/0/ServiceModel/EntityDataService.svc/ContactCollection?$filter=CreatedOn gt datetime'2012-11-01' and CreatedBy/Name eq 'SomeUserName'

public static void GetOdataObjectByFilterDiffConditionExample()
{
    // Name of the user that created the objects.
    string userName = "BPMUserName";
    // Objects creation date.
    string datetime = "2012-11-01";
    // Forming a string of the request to the service.
    string requestUri = serverUri + "ContactCollection?$filter=CreatedOn gt datetime'" + datetime +
                                    "'and CreatedBy/Name eq '" + userName + "'";
    // Creating an object of the request to the service.
    var request = HttpWebRequest.Create(requestUri) as HttpWebRequest;
    request.Method = "GET";
    request.Credentials = new NetworkCredential(userName, "BPMUserPassword");
    using (var response = request.GetResponse())
    {
        // Receiving a response from the service in the xml format.
        XDocument xmlDoc = XDocument.Load(response.GetResponseStream());
        // Receiving the contact objects collection satisfying the request condition.
        var contacts = from entry in xmlDoc.Descendants(atom + "entry")
                       select new
                       {
                           Id = new Guid(entry.Element(atom + "content")
                                             .Element(dsmd + "properties")
                                             .Element(ds + "Id").Value),
                           Name = entry.Element(atom + "content")
                                       .Element(dsmd + "properties")
                                       .Element(ds + "Name").Value
                           // Initiating the object properties required for further use.
                       };
        foreach (var contact in contacts)
        {
            // Implementing actions over the contact.
        }
    }
} 

// Request string:
// POST <BPMonline application address>/0/ServiceModel/EntityDataService.svc/ContactCollection/

public static void CreateBpmEntityByOdataHttpExample()
{
    // Creating a xml message containing data on the created object.
    var content = new XElement(dsmd + "properties",
                  new XElement(ds + "Name", "Jhon Gilts"),
                  new XElement(ds + "Dear", "Jhon"));
    var entry = new XElement(atom + "entry",
                new XElement(atom + "content",
                new XAttribute("type", "application/xml"), content));
    Console.WriteLine(entry.ToString());
    // Creating a request to the service which will add a new object to the contacts collection.
    var request = (HttpWebRequest)HttpWebRequest.Create(serverUri + "ContactCollection/");
    request.Credentials = new NetworkCredential("BPMUserName", "BPMUserPassword");
    request.Method = "POST";
    request.Accept = "application/atom+xml";
    request.ContentType = "application/atom+xml;type=entry";
    // Recording the xml message to the request stream.
    using (var writer = XmlWriter.Create(request.GetRequestStream()))
    {
        entry.WriteTo(writer);
    }
    // Receiving a response from the service regarding the operation implementation result.
    using (WebResponse response = request.GetResponse())
    {
        if (((HttpWebResponse)response).StatusCode == HttpStatusCode.Created)
        {
            // Processing the operation implementation result.
        }
    }
} 

// Request string:
// PUT <BPMonline application address>/0/ServiceModel/EntityDataService.svc/ContactCollection(guid'00000000-0000-0000-0000-000000000000')
// or
// MERGE <Адрес приложения BPMonline>/0/ServiceModel/EntityDataService.svc/ContactCollection(guid'00000000-0000-0000-0000-000000000000')
public static void UpdateExistingBpmEnyityByOdataHttpExample()
{
    // Id of the object record to be modified.
    string contactId = "00000000-0000-0000-0000-000000000000";
    // Creating an xml message containing data on the modified object.
    var content = new XElement(dsmd + "properties",
            new XElement(ds + "Name", "New name")
    );
    var entry = new XElement(atom + "entry",
            new XElement(atom + "content",
                    new XAttribute("type", "application/xml"),
                    content)
            );
    // Creating a request to the service which will modify the object data.
    var request = (HttpWebRequest)HttpWebRequest.Create(serverUri
            + "ContactCollection(guid'" + contactId + "')");
    request.Credentials = new NetworkCredential("BPMUserName", "BPMUserPassword");
    // or request.Method = "MERGE";
    request.Method = "PUT";
    request.Accept = "application/atom+xml";
    request.ContentType = "application/atom+xml;type=entry";
    // Recording the xml message to the request stream.
    using (var writer = XmlWriter.Create(request.GetRequestStream()))
    {
        entry.WriteTo(writer);
    }
    // Receiving a response from the service regarding the operation implementation result.
    using (WebResponse response = request.GetResponse())
    {
        // Processing the operation implementation result.
    }
} 

// Request string:
// DELETE <BPMonline application address>/0/ServiceModel/EntityDataService.svc/ContactCollection(guid'00000000-0000-0000-0000-000000000000')

public static void DeleteBpmEntityByOdataHttpExample()
{
    // Id of the object record to be deleted.
    string contactId = "00000000-0000-0000-0000-000000000000";
    // Creating a request to the service which will delete the data.
    var request = (HttpWebRequest)HttpWebRequest.Create(serverUri
            + "ContactCollection(guid'" + contactId + "')");
    request.Credentials = new NetworkCredential("BPMUserName", "BPMUserPassword");
    request.Method = "DELETE";
    // Receiving a response from the service regarding the operation implementation result.
    using (WebResponse response = request.GetResponse())
    {
        // Processing the operation implementation result.
    }
}