how to send a http basic auth post?

Question

I have been given the task to create a http post using basic auth. I am developing in C# in an asp.net MVC application.

I have also been given this example.

{
POST /v2/token_endpoint HTTP/1.1
Authorization: Basic Y2xpZW50X2lkOmNsaWVudF9zZWNyZXQ=
Accept: application/json
Content-Type: application/x-www-form-urlencoded
User-Agent: Java/1.6.0_33
Host: api.freeagent.com
Connection: close
Content-Length: 127

grant_type=authorization_code&code=12P3AsFZXwXjd7SLOE1dsaX8oCgix&redirect_uri=http%3A%2F%2Flocalhost%3A8080%2Foauth
}

My question is how do i code this in C#? If more information is need just ask, thanks in advance

edit: I have made some progress but I have not added the grant_type

public void AccessToken(string code)
    {
        string url = @"https://api.freeagent.com/v2/token_endpoint";
        WebClient client = new WebClient();
        string credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes(ApiKey + ":" + ApiSecret));
        client.Headers[HttpRequestHeader.Authorization] = "Basic " + credentials;
        client.Headers[HttpRequestHeader.Accept] = "application/json";
        client.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
        client.Headers[HttpRequestHeader.UserAgent] = "Java/1.6.0_33";
        client.Headers[HttpRequestHeader.Host] = "api.freeagent.com";
        client.Headers[HttpRequestHeader.Connection] = "close";
        client.Headers["grant_type"] = "authorization_code";

        var result = client.DownloadString(url);
    }

So how do i add: grant_type=authorization_code&code=12P3AsFZXwXjd7SLOE1dsaX8oCgix&redirect_uri=http%3A%2F%2Flocalhost%3A8080%2Foauth to the post?

Answer 1

You can find here two samples how to make basic auth request with WebRequest and WebClient classes:

http://grahamrhay.wordpress.com/2011/08/22/making-a-post-request-in-c-with-basic-authentication/ http://anishshenoy57.wordpress.com/2013/01/22/basic-http-authentication-using-c/

Basically basic auth it's just Base64(username:password), so it's easy to implement it.

UPDATE1

Here is a sample based on your method:

public void AccessToken(string code)
{
    string url = @"https://api.freeagent.com/v2/token_endpoint";
    WebClient client = new WebClient();
    string credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes(ApiKey + ":" + ApiSecret));
    client.Headers[HttpRequestHeader.Authorization] = "Basic " + credentials;
    client.Headers[HttpRequestHeader.Accept] = "application/json";
    client.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
    client.Headers[HttpRequestHeader.UserAgent] = "Java/1.6.0_33";
    client.Headers[HttpRequestHeader.Host] = "api.freeagent.com";
    client.Headers[HttpRequestHeader.Connection] = "close";
    client.Headers["grant_type"] = "authorization_code";

    string data = string.Format(
        "grant_type=authorization_code&code={0}&redirect_uri=http%3A%2F%2Flocalhost%3A8080",
        code);
    var result = client.UploadString(url, data);
}

The only different in calling method in WebClient. DownloadString will do GET request, but for POST you need to use UploadString method

Answer 2

I too have struggled with this, but I have now made it to the other side!

The one that held me up the most was that if you specify a redirect URL in the Auth Token request, you must also specify it in the Access Token request with the same URL, even though it's not used.

I started off with someones partial wrapper, and have evolved it almost beyond recognition. Hopefully this wrapper (complete with auth and access token code) will help others. I've only used it to create invoices and invoice items so far, and the other functions are untested, but it should get you your tokens and to the point where you can debug the requests.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text;
using System.Web.Script.Serialization;

namespace ClientZone.External
{
    public class FreeAgent
    {
        public enum Methods
        {
            POST = 1,
            PUT
        }

        public enum Status
        {
            Draft = 1,
            Sent,
            Cancelled
        }

        private string _subDomain;
        private string _identifier;
        private string _secret;
        private string _redirectURI;
        public static string AuthToken = "";
        private static string _accessToken = "";
        private static string _refreshToken = "";
        private static DateTime _refreshTime;

        public FreeAgent(string identifier, string secret, string subdomain, string redirectURI)
        {
            _subDomain = subdomain;
            _identifier = identifier;
            _secret = secret;
            _redirectURI = redirectURI; // If this was specified in the Auth Token call, you must specify it here, and it must be the same
        }

        public bool GetAccessToken()
        {
            try
            {
                string url = @"https://api.freeagent.com/v2/token_endpoint";
                WebClient client = new WebClient();
                string credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes(_identifier + ":" + _secret));
                client.Headers[HttpRequestHeader.Host] = "api.freeagent.com";
                client.Headers[HttpRequestHeader.KeepAlive] = "true";
                client.Headers[HttpRequestHeader.Accept] = "application/json";
                client.Headers[HttpRequestHeader.UserAgent] = "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/45.0.2454.93 Safari/537.36";
                client.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded;charset=UTF-8";

                client.Headers[HttpRequestHeader.Authorization] = "Basic " + credentials;
                System.Net.ServicePointManager.Expect100Continue = false;
                client.Headers[HttpRequestHeader.AcceptEncoding] = "gzip, deflate";
                client.Headers[HttpRequestHeader.AcceptLanguage] = "en-US,en;q=0.8";

                var result = "";
                if (!(_accessToken == "" && _refreshToken != ""))
                {
                    string data = string.Format("grant_type=authorization_code&code={0}&redirect_uri={1}", AuthToken, _redirectURI);
                    result = client.UploadString(url, data);
                }
                else
                {
                    // Marking the access token as blank and the refresh token as not blank
                    // is a sign we need to get a refresh token
                    string data = string.Format("grant_type=refresh_token&refresh_token={0}", _refreshToken);
                    result = client.UploadString(url, data);
                }

                JavaScriptSerializer json_serializer = new JavaScriptSerializer();
                var results_list = (IDictionary<string, object>)json_serializer.DeserializeObject(result);
                _accessToken = results_list["access_token"].ToString();
                int secondsUntilRefresh = Int32.Parse(results_list["expires_in"].ToString());
                _refreshTime = DateTime.Now.AddSeconds(secondsUntilRefresh);
                if (results_list.Any(x => x.Key == "refresh_token"))
                {
                    _refreshToken = results_list["refresh_token"].ToString();
                }

                if (_accessToken == "" || _refreshToken == "" || _refreshTime == new DateTime())
                {
                    return false;
                }

            }
            catch
            {
                return false;
            }

            return true;
        }

        private HttpStatusCode SendWebRequest(Methods method, string URN, string request, out string ResponseData)
        {
            if (_accessToken == "")
            {
                // The access token has not been retrieved yet
                GetAccessToken();
            }
            else
            {
                if (_refreshTime != new DateTime() && _refreshTime < DateTime.Now) {
                    // The token has expired and we need to refresh it
                    _accessToken = "";
                    GetAccessToken();
                }
            }

            if (_accessToken != "")
            {
                try
                {
                    WebClient client = new WebClient();
                    string url = "https://api.freeagentcentral.com/v2/" + URN;
                    client.Headers[HttpRequestHeader.UserAgent] = "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/45.0.2454.93 Safari/537.36";
                    client.Headers[HttpRequestHeader.Authorization] = "Bearer " + _accessToken;
                    client.Headers[HttpRequestHeader.ContentType] = "application/json";
                    client.Headers[HttpRequestHeader.Accept] = "application/json";

                    if (method == Methods.POST || method == Methods.PUT)
                    {
                        string data = request;
                        var result = client.UploadString(url, method.ToString(), data);
                        ResponseData = result;
                        return HttpStatusCode.Created;
                    }
                    else
                    {
                        var result = client.DownloadString(url);
                        ResponseData = result;
                        return HttpStatusCode.OK;
                    }
                }
                catch (WebException e)
                {
                    if (e.GetType().Name == "WebException")
                    {
                        WebException we = (WebException)e;
                        HttpWebResponse response = (System.Net.HttpWebResponse)we.Response;

                        ResponseData = response.StatusDescription;
                        return response.StatusCode;
                    }
                    else
                    {
                        ResponseData = e.Message;
                        if (e.InnerException != null)
                        {
                            ResponseData = ResponseData + " - " + e.InnerException.ToString();
                        }
                        return HttpStatusCode.SeeOther;
                    }
                }
            }
            else
            {
                ResponseData = "Access Token could not be retrieved";
                return HttpStatusCode.SeeOther;
            }
        }

        private int ExtractNewID(string resp, string URN)
        {
            if (resp != null && resp.Trim() != "")
            {
                JavaScriptSerializer json_serializer = new JavaScriptSerializer();
                var results_list = (IDictionary<string, object>)json_serializer.DeserializeObject(resp);

                if (results_list.Any(x => x.Key == "invoice"))
                {
                    var returnInvoice = (IDictionary<string, object>)results_list["invoice"];

                    if (returnInvoice["created_at"].ToString() != "")
                    {
                        string returnURL = returnInvoice["url"].ToString();

                        if (returnURL.Contains("http"))
                        {
                            return int.Parse(returnURL.Remove(0, ("https://api.freeagentcentral.com/v2/" + URN).Length + 1));
                        }
                        else
                        {
                            return int.Parse(returnURL.Remove(0, URN.Length + 2));
                        }
                    }
                }
            }

            return -1;
        }

        public int CreateContact(string firstName, string lastName, string emailAddress, string street, string city, string state, string postcode, string country)
        {
            StringBuilder request = new StringBuilder();

            request.Append("{\"contact\":{");
            request.Append("\"first-name\":");
            request.Append(firstName);
            request.Append("\",");
            request.Append("\"last-name\":");
            request.Append(lastName);
            request.Append("\",");
            request.Append("\"email\":");
            request.Append(emailAddress);
            request.Append("\",");

            request.Append("\"address1\":");
            request.Append(street);
            request.Append("\",");
            request.Append("\"town\":");
            request.Append(city);
            request.Append("\",");
            request.Append("\"region\":");
            request.Append(state);
            request.Append("\",");
            request.Append("\"postcode\":");
            request.Append(postcode);
            request.Append("\",");
            request.Append("\"country\":");
            request.Append(country);
            request.Append("\"");

            request.Append("}");

            string returnData = string.Empty;

            HttpStatusCode responseCode = SendWebRequest(Methods.POST, "contacts", request.ToString(), out returnData);
            if (responseCode == HttpStatusCode.OK || responseCode == HttpStatusCode.Created)
            {
                return ExtractNewID(returnData, "contacts");
            }
            else
            {
                return -1;
            }
        }

        public int CreateInvoice(int contactID, DateTime invoiceDate, int terms, string reference, string comments, string currency = "GBP")
        {
            StringBuilder request = new StringBuilder();

            request.Append("{\"invoice\":{");
            request.Append("\"dated_on\": \"");
            request.Append(invoiceDate.ToString("yyyy-MM-ddTHH:mm:00Z"));
            request.Append("\",");

            if (!string.IsNullOrEmpty(reference))
            {
                request.Append("\"reference\": \"");
                request.Append(reference);
                request.Append("\",");
            }

            if (!string.IsNullOrEmpty(comments))
            {
                request.Append("\"comments\": \"");
                request.Append(comments);
                request.Append("\",");
            }

            request.Append("\"payment_terms_in_days\": \"");
            request.Append(terms);
            request.Append("\",");

            request.Append("\"contact\": \"");
            request.Append(contactID);
            request.Append("\",");

            if (currency == "EUR")
            {
                request.Append("\"ec_status\": \"");
                request.Append("EC Services");
                request.Append("\",");
            }

            request.Append("\"currency\": \"");
            request.Append(currency);
            request.Append("\"");

            request.Append("}}");

            string returnData = string.Empty;

            HttpStatusCode responseCode = SendWebRequest(Methods.POST, "invoices", request.ToString(), out returnData);
            if (responseCode == HttpStatusCode.OK || responseCode == HttpStatusCode.Created)
            {
                return ExtractNewID(returnData, "invoices");
            }
            else
            {
                return -1;
            }
        }

        public bool ChangeInvoiceStatus(int invoiceID, Status status)
        {
            string returnData = string.Empty;

            HttpStatusCode resp = SendWebRequest(Methods.PUT, "invoices/" + invoiceID.ToString() + "/transitions/mark_as_" + status.ToString().ToLower(), string.Empty, out returnData);

            return false;
        }

        public int CreateInvoiceItem(int invoiceID, string itemType, float price, int quantity, float taxRate, string description)
        {
            StringBuilder request = new StringBuilder();

            request.Append("{\"invoice\":{");
            request.Append("\"invoice_items\":[{");

            request.Append("\"item_type\": \"");
            request.Append(itemType);
            request.Append("\",");

            request.Append("\"price\": \"");
            request.Append(price.ToString("0.00"));
            request.Append("\",");

            request.Append("\"quantity\": \"");
            request.Append(quantity);
            request.Append("\",");

            request.Append("\"sales_tax_rate\": \"");
            request.Append(taxRate.ToString("0.00"));
            request.Append("\",");

            request.Append("\"description\": \"");
            request.Append(description);
            request.Append("\"");

            request.Append("}]");
            request.Append("}");
            request.Append("}");

            string returnData = string.Empty;

            HttpStatusCode responseCode = SendWebRequest(Methods.PUT, "invoices/" + invoiceID.ToString(), request.ToString(), out returnData);
            if (responseCode == HttpStatusCode.OK || responseCode == HttpStatusCode.Created)
            {
                // Invoice items is an update call to an invoice, so we just get a 200 OK with no response body to extract an ID from
                return 0;
            }
            else
            {
                return -1;
            }
        }
    }
}

To use this in an MVC setup you need to detect in the Index whether the login is necessary or not. If it is, you tell FreeAgent to come back to another ActionResult (I've used Auth) to catch the redirect and store the code.

    public ActionResult Index()
    {
        if (MyNamespace.External.FreeAgent.AuthToken == "")
        {
            return Redirect("https://api.freeagent.com/v2/approve_app?redirect_uri=" + Request.Url.Scheme + "://" + Request.Url.Authority + "/Invoice/Auth" + "&response_type=code&client_id=1234567890123456789012");

        }
        else
        {
            return View();
        }
    }


    public ActionResult Auth()
    {
        if (Request.Params.Get("code").ToString() != "")
        {
            ClientZone.External.FreeAgent.AuthToken = Request.Params.Get("code").ToString();
        }

        return View("Index");
    }

Then to use the functions all you need is

MyNameSpace.External.FreeAgent FA = new ClientZone.External.FreeAgent("abcdefghhijklmnopqrstu", "1234567890123456789012", "acme", "http://localhost:52404/Invoice/Auth");

int newID = FA.CreateInvoice(54321, InvoiceDate, 30, "", "", "GBP");
if (newID != -1)
{
    FA.CreateInvoiceItem(newID, unit, rate, quantity, number, description);
}

There is some UK/EU specific coding in the CreateInvoice. I'm not sure how custom or standard this is, but I've left it in as it's easier to delete it than recreate it.