In my .NET project, I have to use HTTP GET request to get weather info for my city from API. Because of my JavaScript background I thought "OK, so all I need is something like app.get(url, body)", so I started with something like this:
using (var client = new WebClient())
{
var responseString = client.DownloadString("http://www.webservicex.net/globalweather.asmx/GetWeather?CityName=" + city + "&CountryName=" + country);
string xmlString = DecodeXml(responseString);
return xmlString;
}
Unfortunately for me it turned out, that I have to use WCF to get the data. I searched the web for some tutorials, but I couldn't find anything with getting the data from outer sources, just creating own API.
I'm not a native speaker, so maybe I'm just out of words to look for the solution, but it would be awesome if you could give me some advice.
Assuming you are using Visual Studio. Add Service Reference, and then type "http://www.webservicex.net/globalweather.asmx" into the address and hit Go. It'll auto-generate the end point for you to use.
Then the code is something like:
ServiceReference1.GlobalWeatherSoapClient client = new ServiceReference1.GlobalWeatherSoapClient("GlobalWeatherSoap");
string cities = client.GetCitiesByCountry("Hong Kong");
If you want to just use HTTP GET, you can do something like this:
var city = "Dublin";
var country = "Ireland";
WebRequest request = WebRequest.Create(
"http://www.webservicex.net/globalweather.asmx/GetWeather?CityName=" +
city +
"&CountryName=" + country);
request.Credentials = CredentialCache.DefaultCredentials;
WebResponse response = request.GetResponse();
Console.WriteLine(((HttpWebResponse)response).StatusDescription);
Stream dataStream = response.GetResponseStream();
StreamReader reader = new StreamReader(dataStream);
string responseFromServer = reader.ReadToEnd();
Console.WriteLine(responseFromServer);
reader.Close();
response.Close();
Console.ReadLine();
Please note, I have not HTML decoded the response here, you can simply use HttpUtility.HtmlDecode for that.
Also, you will need to include the following using statements:
using System.IO;
using System.Net;
Related
Web-page data into the application
You can replicate the request the website makes to get a list of relevant numbers. The following code might be a good start.
var httpRequest = (HttpWebRequest) WebRequest.Create("<url>");
httpRequest.Method = "POST";
httpRequest.Accept = "application/json";
string postData = "{<json payload>}";
using (var streamWriter = new StreamWriter(httpRequest.GetRequestStream())) {
streamWriter.Write(postData);
}
var httpResponse = (HttpWebResponse) httpRequest.GetResponse();
string result;
using (var streamReader = new StreamReader(httpResponse.GetResponseStream())) {
result = streamReader.ReadToEnd();
}
Console.WriteLine(result);
Now, for the <url> and <json payload> values:
Open the web inspector in your browser.
Go to the Network tab.
Set it so Fetch/XHR/AJAX requests are shown.
Refresh the page.
Look for a request that you want to replicate.
Copy the request URL.
Copy the Payload (JSON data, to use it in your code you'll have to add a \ before every ")
Side note: The owner of the website you are making automated requests to might not be very happy about your tool, and you/it might be blocked if it makes too many requests in a short time.
I have jobs in Jenkins that i cannot access unless i log in first using a my username and password.
For example if i try to access "localhost:xxx/job/some_job_1" i will get a 404 Error unless i log in first. And i say this because i have tried the following using WebRequest class:
string formParams = "j_username=bobbyLee&j_password=SecretPassword25&from=%2F&json=%7B%22j_username%22%3A+%bobbyLee%22%2C+%22j_password%22%3A+%22SecretPassword%25%22%2C+%22remember_me%22%3A+false%2C+%22from%22%3A+%22%2F%22%7D&Submit=log+in";
// ***this is the exact string that is sent when i log in normally, obtained using Fiddler***
string formUrl = "http://serverName:PortNum/j_acegi_security_check";
// ***I have also tried http://serverName:PortNum/login***
string cookieHeader;
WebRequest req = WebRequest.Create(formUrl);
req.ContentType = "application/x-www-form-urlencoded";
req.Method = "POST";
byte[] bytes = Encoding.ASCII.GetBytes(formParams);
req.ContentLength = bytes.Length;
using (Stream os = req.GetRequestStream())
{
os.Write(bytes, 0, bytes.Length);
}
WebResponse resp = req.GetResponse();
cookieHeader = resp.Headers["Set-cookie"];
string pageSource;
string getUrl = "http://serverName:portNum/job/some_job/";
WebRequest getRequest = WebRequest.Create(getUrl);
getRequest.Headers.Add("Cookie", cookieHeader);
WebResponse getResponse = getRequest.GetResponse();
using (StreamReader sr = new StreamReader(getResponse.GetResponseStream()))
{
pageSource = sr.ReadToEnd();
}
The response that i get back from the POST request is "HTML OK", and cookieHeader is not null. But when i then try to make a GET request to get what i want, i get a 404 error when attempting to access the job "http://serverName:portNum/job/some_job/", as if i didn't log in successfully.
So what is the correct way to log into Jenkins from c#, and get the HTML source code of the jobs that only appears after logging in?
The RESTAPI is your best friend here.
It is an incredibly rich source of information. I have written a system that will show an entire program of work on a page with full deployment traceability.
I am going to assume you have some security in place in your Jenkins instance which means requests need to be authenticated.
I use the following class for this:
using System;
using System.Net;
using System.Text;
namespace Core.REST
{
public class HttpAdapter
{
private const string ApiToken = "3abcdefghijklmnopqrstuvwxyz12345"; // you will need to change this to the real value
private const string UserName = "restapi";
public string Get(string url)
{
try
{
const string credentials = UserName + ":" + ApiToken;
var authorization = Convert.ToBase64String(Encoding.ASCII.GetBytes(credentials));
using (var wc = new WebClient())
{
wc.Headers[HttpRequestHeader.Authorization] = "Basic " + authorization;
var htmlResult = wc.DownloadString(string.Format(url));
return htmlResult;
}
}
catch (WebException e)
{
Console.WriteLine("Could not retrieve REST API response");
throw e;
}
}
}
}
restapi is a dedicated user I created. I think I gave it admin access just so I didn't have to worry about it. I was admin but all the other developers and testers in the 3 crews had highly controlled and limited access to only what they needed and nothing more. It is also better practice to have a dedicated users for functions like this.
I constructed my c# classes to consume (deserialise) data from any page that supports the api/json suffix.
I am working on a c# console application where I am making a Http Post request to a web api by using xml file and I'm kind of new to XML and web services but I figured out the following code for the request but failed to pass xml data to the method
static void Main(string[] args)
{
string desturl=#"https://xyz.abcgroup.com/abcapi/";
Program p = new Program();
System.Console.WriteLine(p.WebRequestPostData(desturl, #"C:\Applications\TestService\FixmlSub.xml"));
}
public string WebRequestPostData(string url, string postData)
{
System.Net.WebRequest req = System.Net.WebRequest.Create(url);
req.ContentType = "text/xml";
req.Method = "POST";
byte[] bytes = System.Text.Encoding.ASCII.GetBytes(postData);
req.ContentLength = bytes.Length;
using (Stream os = req.GetRequestStream())
{
os.Write(bytes, 0, bytes.Length);
}
using (System.Net.WebResponse resp = req.GetResponse())
{
if (resp == null) return null;
using (System.IO.StreamReader sr = new System.IO.StreamReader(resp.GetResponseStream()))
{
return sr.ReadToEnd().Trim();
}
}
}
For obvious reasons the above code throws 404 error as I think I am not passing the xml data properly
May I know how I can fix this?
You're not posting xml, your posting the string C:\Applications\TestService\FixmlSub.xml
Change your method call from:
System.Console.WriteLine(p.WebRequestPostData(desturl, #"C:\Applications\TestService\FixmlSub.xml"));
to
var xml = XElement.Load(#"C:\Applications\TestService\FixmlSub.xml");
System.Console.WriteLine(p.WebRequestPostData(desturl, xml.ToString(SaveOptions.DisableFormatting));
If you are trying to learn post / receive, go for it. But there are open source libraries that are already well tested to use if you want to use them.
The non-free version of Servicestack.
And their older free-version. I think the older free version is great. I've never tried the newer one. You deal with objects, like say an Employee and pass that to the library and it does the translation to xml or whatever the web-service wants.
You can post whole strings if you want. They have great extension methods to help you with that too.
I have a REST Service that accepts a id in the URL for PUT requests. So far the PUT request looks like this:
string url = "http://localhost:3596/WidgetManager.svc/Widgets/" + TextBox3.Text;
WebRequest req = WebRequest.Create(url);
req.Method = "PUT";
using (HttpWebResponse resp = req.GetResponse() as HttpWebResponse)
{
StreamReader reader = new StreamReader(resp.GetResponseStream());
Label4.Text = reader.ReadToEnd();
}
But I also need to send a Widget object in my request.
Widget w = new Widget();
w.Name = "worked!!!";
w.CogCount = 1000;
w.SprocketSize = 2000;
I saw a lot of examples on how to send strings. But what about objects like this?
You could serialise it using XML or JSON.
If it is such a small object, you could write your own small method like
.toJSON() {
return '{"Name":"' + this.name + '", "CogCount":' + this.CogCount + ', "SprocketSize":' + this.SprocketSize + '}';
}
//Output: '{"Name":"worked!!!", "CogCount":1000, "SprocketSize":2000}'
On the other hand: C# provides powerful (XML) serialisation tools!
This here: http://www.codeproject.com/Articles/1789/Object-Serialization-using-C is only one of many examples.
But if you use PHP or similar, JSON might even be more interesting.
I am having difficulty in consuming the reCaptcha Web Service using C#/.Net 3.5. Although I think the problem is with consuming web services in general.
String validate = String.Format("http://api-verify.recaptcha.net/verify?privatekey={0}&remoteip={1}&challenge={2}&response={3}", PrivateKey, UserIP, Challenge, Response);
WebClient serviceRequest = new WebClient();
serviceRequest.Headers.Add("ContentType","application/x-www-form-urlencoded")
String response = serviceRequest.DownloadString(new Uri(validate ));
It keeps telling me that the error is: nverify-params-incorrect. Which means:
The parameters to /verify were incorrect, make sure you are passing all the required parameters.
But it's correct. I am using the private key, the IP address (locally) is 127.0.0.1, and the challenge and response seem fine. However the error keeps occurring.
I am pretty sure this is a issue with how I am requesting the service as this is the first time I have actually used webservices and .Net.
I also tried this as it ensures the data is posted:
String queryString = String.Format("privatekey={0}&remoteip={1}&challenge={2}&response={3}",PrivateKey, UserIP, Challenge, Response);
String Validate = "http://api-verify.recaptcha.net/verify" + queryString;
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(new Uri(Validate));
request.Method = "POST";
request.ContentType = "application/x-www-form-urlencoded";
request.ContentLength = Validate.Length;
**HttpWebResponse captchaResponse = (HttpWebResponse)request.GetResponse();**
String response;
using (StreamReader reader = new StreamReader(captchaResponse.GetResponseStream()))
response = reader.ReadToEnd();
Seems to stall at the point where I get response.
Any advice?
Thanks in advance
Haven't worked with the recaptcha service previously, but I have two troubleshooting recommendations:
Use Fiddler or Firebug and watch what you're sending outbound. Verifying your parameters would help you with basic troubleshooting, i.e. invalid characters, etc.
The Recaptcha Wiki has an entry about dealing with development on Vista. It doesn't have to be limited to Vista, though; if you're system can handle IPv6, then your browser could be communicating in that format as a default. It appears as if Recaptcha deals with IPv4. Having Fiddler/Firebug working would tell you about those other parameters that could be causing you grief.
This may not help solve your problem but it might provide you with better troubleshooting info.
So got this working, for some reason I needed to write the request to a stream like so:
//Write data to request stream
using (Stream requestSteam = request.GetRequestStream())
requestSteam.Write(byteData, 0, byteData.Length);
Could anyone explain why this works. I didn't think I would need to do this, don't completely understand what's happening behind the scenes..
Damien's answer is correct of course, but just to be clear about the order of things (I was a little confused) and to have a complete code sample...
var uri = new Uri("http://api-verify.recaptcha.net/verify");
var queryString = string.Format(
"privatekey={0}&remoteip={1}&challenge={2}&response={3}",
privateKey,
userIP,
challenge,
response);
var request = (HttpWebRequest)HttpWebRequest.Create(uri);
request.Method = WebRequestMethods.Http.Post;
request.ContentLength = queryString.Length;
request.ContentType = "application/x-www-form-urlencoded";
using (var writer = new StreamWriter(request.GetRequestStream()))
{
writer.Write(queryString);
}
string result;
using (var webResponse = (HttpWebResponse)request.GetResponse())
{
var reader = new StreamReader(webResponse.GetResponseStream());
result = reader.ReadToEnd();
}
There's a slight difference in that I'm writing the post variables to the request, but the core of it is the same.