I am encountering an unusually strange behavior when POSTing a Json string to a PHP webserver. I use the JsonTextWriter object to create the Json string. I then send the Json string as a POST request. Please see comments. The HTML response in the code is returning the correct output, but when viewed in a browser, the web page displays either NULL or array(0) { }.
private void HttpPost(string uri, string parameters)
{
WebRequest webRequest = WebRequest.Create(uri);
webRequest.ContentType = "application/x-www-form-urlencoded"; // <- Should this be "application/json" ?
webRequest.Method = "POST";
byte[] bytes = Encoding.UTF8.GetBytes(parameters);
string byteString = Encoding.UTF8.GetString(bytes);
Stream os = null;
try
{ // Send the Post Data
webRequest.ContentLength = bytes.Length;
os = webRequest.GetRequestStream();
os.Write(bytes, 0, bytes.Length);
Console.WriteLine(String.Format(#"{0}", byteString)); // <- This matches the Json object
}
catch (WebException ex)
{ //Handle Error }
try
{ // Get the response
WebResponse webResponse = webRequest.GetResponse();
if (webResponse == null) { return null; }
StreamReader sr = new StreamReader(webResponse.GetResponseStream());
Console.WriteLine(sr.ReadToEnd().Trim()); // <- Server returns string response (full HTML page)
}
catch (WebException ex)
{ //Handle Error }
}
Relevant PHP code on the server:
$json = json_encode($_POST); # Not 'standard way'
var_dump(json_decode($json));
Any suggestions would be greatly appreciated.
Thanks
Try using "application/json" as the content type. Also, check the request logs or maybe do a port 80 trace if you can to view what's being sent to the server in the request body.
You can also narrow the scope of the problem -- is it the C# code or the PHP code that's bad -- by writing a quick JQuery ajax function that sends some JSON to the PHP server. This isolation of the PHP code from the C# code will tell you if the PHP is at least working correctly. If it is, then the problem is in the C# code.
Related
I'm trying to get the order book from GDAX (link to documentation of the call) but when doing it from the c# executable I always get Error 400 - Bad request.
When taking the actual URL and pasting it into my browser, it works fine.
String URL = "https://api.gdax.com/products/BTC-USD/book?level=2";
WebRequest request = WebRequest.Create(URL);
WebResponse response = request.GetResponse();
The actual issue with your API call is , the API is expecting a user-agent string while making the request: Below is the code in working condition:
try
{
String URL = "http://api.gdax.com/products/BTC-USD/book?level=2";
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(URL);
request.UserAgent = ".NET Framework Test Client";
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
var encoding = ASCIIEncoding.ASCII;
using (var reader = new System.IO.StreamReader(response.GetResponseStream(), encoding))
{
string responseText = reader.ReadToEnd();
}
}
catch(WebException ex)
{
HttpWebResponse xyz = ex.Response as HttpWebResponse;
var encoding = ASCIIEncoding.ASCII;
using (var reader = new System.IO.StreamReader(xyz.GetResponseStream(), encoding))
{
string responseText = reader.ReadToEnd();
}
}
Basically ProtocolError indicates that you have received the response but there is an error related to protocol, which you can observe, when you read the response content from exception. I have added catch to handle the exception and read ex.Response (which is HttpWebResponse) and could see that the API is asking for user-agent to be suppllied while making the call. I got to see the error as "{"message":"User-Agent header is required."}"
You can ignore the code inside the exception block, I used it only to see what is the actual response message, which contains actual error details
Note: I have boxed WebRequest to HttpWebRequest to have additional http protocol related properties and most importantly "UserAgent" property which is not available with the WebRequest class.
You need to Accept the certificarte, Google for access to a https webrequest.
Like this
I originally asked a question regarding a WCF web service that I was trying to write and then found that the ASP.net web API was more appropriate to my needs, due to some feedback on here.
I've now found a good tutorial that tells me how to create a simple REST service using Web API which works well pretty much out of the box.
My question
I have a POST method in my REST service server:
// POST api/values/5
public string Post([FromBody]string value)
{
return "Putting value: " + value;
}
I can POST to this using POSTER and also my C# client code.
However the bit I don't understand is why I have to prepend an '=' sign to the POST data so that it reads: "=Here is my data which is actually a JSON string"; rather than just sending: "Here is my data which is actually a JSON string";
My C# Client that talks to the REST service is written as follows:
public string SendPOSTRequest(string sFunction, string sData)
{
string sResponse = string.Empty;
// Create the request string using the data provided
Uri uriRequest = GetFormRequest(m_sWebServiceURL, sFunction, string.Empty);
// Data to post
string sPostData = "=" + sData;
// The Http Request obj
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uriRequest);
request.Method = m_VERB_POST;
System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
Byte[] byteArray = encoding.GetBytes(sPostData);
request.ContentLength = byteArray.Length;
request.ContentType = m_APPLICATION_FORM_URLENCODED;
try
{
using (Stream dataStream = request.GetRequestStream())
{
dataStream.Write(byteArray, 0, byteArray.Length);
}
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
using (Stream stream = response.GetResponseStream())
{
StreamReader reader = new StreamReader(stream, Encoding.UTF8);
sResponse = reader.ReadToEnd();
}
}
}
catch (WebException ex)
{
//Log exception
}
return sResponse;
}
private static Uri GetFormRequest(string sURL, string sFunction, string sParam)
{
StringBuilder sbRequest = new StringBuilder();
sbRequest.Append(sURL);
if ((!sURL.EndsWith("/") &&
(!string.IsNullOrEmpty(sFunction))))
{
sbRequest.Append("/");
}
sbRequest.Append(sFunction);
if ((!sFunction.EndsWith("/") &&
(!string.IsNullOrEmpty(sParam))))
{
sbRequest.Append("/");
}
sbRequest.Append(sParam);
return new Uri(sbRequest.ToString());
}
Is anybody able to explain why I have to prepend the '=' sign as in the above code (string sPostData = "=" + sData;)?
Many thanks in advance!
The content type x-www-form-urlencoded is a key-value format. With form bodies you are only able to read a single simple type from a request body. As a name is expected, but in this case not allowed, you have to prefix the equal sign to indicate that there is no name with the followed value.
However, you should lean away from accepting simple types within the body of your web-api controller actions.
You are limited to only a single simple type if you attempt to pass data in the body of an HttpPost/HttpPut without directly implementing your own MediaTypeFormatter, which is unlikely to be reliable. Creating a light-weight complex type is generally much more preferable, and will make interoperating with other content-types, like application/json, much easier.
I currently have the code
try
{
string url = "http://myanimelist.net/api/animelist/update/" + "6.xml";
WebRequest request = WebRequest.Create(url);
request.ContentType = "xml/text";
request.Method = "POST";
request.Credentials = new NetworkCredential("username", "password");
byte[] buffer = Encoding.GetEncoding("UTF-8").GetBytes("<episode>4</episode>");
Stream reqstr = request.GetRequestStream();
reqstr.Write(buffer, 0, buffer.Length);
reqstr.Close();
MessageBox.Show("Updated");
}
catch (Exception s)
{
MessageBox.Show(s.Message);
}
I am trying do send data to myanimelist.net
The code they have written for is this
URL: http://myanimelist.net/api/animelist/update/id.xml
Formats: xml
HTTP Method(s): POST
Requires Authentication:true
Parameters:
id. Required. The id of the anime to update.
Example: http://myanimelist.net/api/animelist/update/21.xml
data. Required. A parameter specified as 'data' must be passed. It must contain anime values in XML format.
Response: 'Updated' or detailed error message.
The usage code example the have stated is this, does anyone know how to do this in c# or what was wrong with my original code?
Usage Examples:
CURL: curl -u user:password -d data="XML" http://myanimelist.net/api/animelist/update/21.xml
edit: When i lauch myanimelist.net it shows that it has not been updated, i am sure that my username and password credentials are correct
Edit 2 : I have now added a response which comes up with the error
"The remote server returned an error: (501) Not Implemented."
You're not actually performing the request, so once you're done writing to the request stream itself, perform the actual web request:
string result;
using (HttpWebResponse response = (HttpWebResponse)request.GetResponse())
{
using (StreamReader reader = new StreamReader(response.GetResponseStream()))
{
result = reader.ReadToEnd();
}
}
Also, the content type should be text/xml or application/xml - the API may be complaining about that. Read the documentation for their API carefully and ensure what you're sending is correct.
I am getting The remote server returned an error: (400) Bad Request error while running the following code.
I am trying to upload xml file on the http server.
My xml file contains tag for the username,password and domain and when i am trying to connect is manually i am able to connect it,but using same credentials when i am trying to connect it through this code, i am getting 400 Bad Request error.
Please suggest me how to overcome this issue.
Thanks
`
public static void UploadHttp(string xml)
{
string txtResults = string.Empty;
try
{
string url = "http://my.server.com/upload.aspx ";
HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(url);
request.KeepAlive = false;
request.SendChunked = true;
request.AllowAutoRedirect = true;
request.Method = "Post";
request.ContentType = "text/xml";
var encoder = new UTF8Encoding();
var data = encoder.GetBytes(xml);
request.ContentLength = data.Length;
var reqStream = request.GetRequestStream();
reqStream.Write(data, 0, data.Length);
reqStream.Close();
WebResponse response = null;
response = request.GetResponse();
var reader = new StreamReader(response.GetResponseStream());
var str = reader.ReadToEnd();
}
catch (WebException ex)
{
if (ex.Status == WebExceptionStatus.ProtocolError)
{
HttpWebResponse err = ex.Response as HttpWebResponse;
if (err != null)
{
string htmlResponse = new StreamReader(err.GetResponseStream()).ReadToEnd();
txtResults = string.Format("{0} {1}", err.StatusDescription, htmlResponse);
}
}
else
{
}
}
catch (Exception ex)
{
txtResults = ex.ToString();
}
}`
Are you sure you should be using POST not PUT?
POST is usually used with application/x-www-urlencoded formats. If you are using a REST API, you should maybe be using PUT? If you are uploading a file you probably need to use multipart/form-data. Not always, but usually, that is the right thing to do..
Also you don't seem to be using the credentials to log in - you need to use the Credentials property of the HttpWebRequest object to send the username and password.
400 Bad request Error will be thrown due to incorrect authentication entries.
Check if your API URL is correct or wrong. Don't append or prepend spaces.
Verify that your username and password are valid. Please check any spelling mistake(s) while entering.
Note: Mostly due to Incorrect authentication entries due to spell changes will occur 400 Bad request.
What type of authentication do you use?
Send the credentials using the properties Ben said before and setup a cookie handler.
You already allow redirection, check your webserver if any redirection occurs (NTLM auth does for sure). If there is a redirection you need to store the session which is mostly stored in a session cookie.
//use "ASCII" or try with another encoding scheme instead of "UTF8".
using (StreamWriter postStream = new StreamWriter(request.GetRequestStream(), System.Text.Encoding.UTF8))
{
postStream.Write(postData);
postStream.Close();
}
from my windows application i am trying to send xml to fedex url and expecting response back from fedex. i am getting error "The remote server returned an error: (500) Internal Server Error."
what is the meaning of this error and why i am getting this error because the url i got from fedex support people....so i think the service url is right. here i am giving my code by which i am trying to send xml to fedex service url.
public string Post(string sXml)
{
string Err = "";
WebResponse WebRes = null;
string sResponse = "";
try
{
string URL = "https://gatewaybeta.fedex.com:443/web-services/ship"; // "https://ws.fedex.com:443/web-services/ship";
byte[] buffer = Encoding.UTF8.GetBytes(sXml);
HttpWebRequest WebReq = (HttpWebRequest)WebRequest.Create(URL);
WebReq.Method = "POST";
WebReq.ContentType = "application/x-www-form-urlencoded";
WebReq.ContentLength = buffer.Length;
Stream ReqStream = WebReq.GetRequestStream();
ReqStream.Write(buffer, 0, buffer.Length);
ReqStream.Close();
WebRes = WebReq.GetResponse();
Stream ResStream = WebRes.GetResponseStream();
StreamReader ResReader = new StreamReader(ResStream);
sResponse = ResReader.ReadToEnd();
}
catch (Exception ex)
{
Err = ex.Message.ToString();
}
finally
{
}
return sResponse;
}
is there any error in my code. please guide why i am getting error. i am talking to fedex support but not getting any technical help from them.
thanks
The error message is from the Fedex server, but the cause of the error is probably in the URL you send their server, probably in the form of illegal arguments. Double check the Fedex URL requirements.
If you are using Plain XML (not SOAP), use:
https://wsbeta.fedex.com/xml
https://ws.fedex.com/xml