Develop Reference

How can I use a google speech to text api key in deployed WPF app?

I have created a C# WPF app that uses google Speech-to-Text API. Currently, on my development machine, I have added an environment variable in windows, which references to the JSON file that google gave me.
Will I need to create that environment variable to every machine I deploy my app or is there a way to somehow store the JSON key on a server and reference it from there?

Possibly, Passing Credentials Using Code helps you.
This is the code copied from there:
// Some APIs, like Storage, accept a credential in their Create()
// method.
public object AuthExplicit(string projectId, string jsonPath)
{
// Explicitly use service account credentials by specifying
// the private key file.
var credential = GoogleCredential.FromFile(jsonPath);
var storage = StorageClient.Create(credential);
// Make an authenticated API request.
var buckets = storage.ListBuckets(projectId);
foreach (var bucket in buckets)
{
Console.WriteLine(bucket.Name);
}
return null;
}
// Other APIs, like Language, accept a channel in their Create()
// method.
public object AuthExplicit(string projectId, string jsonPath)
{
LanguageServiceClientBuilder builder = new LanguageServiceClientBuilder
{
CredentialsPath = jsonPath
};
LanguageServiceClient client = builder.Build();
AnalyzeSentiment(client);
return 0;
}

How can I call a method when my web API is initialized?

I am building a web API that will serve as a connector between a 3rd-party application and mine.
This application will be running on a server and will be receiving POST requests from the 3rd-party application and sending POST requests of its own as a response.
Before it starts sending these requests, my web API needs to make a POST to the 3rd-party service, so it can be registered and received an authorization token, that it will be used on the requests it sends back, kinda similar to an OAuth token, from what I understand.
Since my code is all inside an HttpPost method, it only gets activated when it receives a call, and that part work as expected. When the service is authenticated and is receiving requests, is fine. The problem is when my service or the 3rd-party is restarted or something, the current token is made invalid or lost and a new one needs to be requested again.
What I wish to do is make that the call to register my service and receive the token is sent when the service starts, automatically.
Currently I am doing a manual call to trigger when my service needs to be registered, but that make it necessary for me to be at my computer to do so, and the connection is not make until I call that request.
Here is a sample of my code:
public class Controller : ApiController
{
static string SessionToken = "";
[HttpPost]
[Route("connector/webhook")]
public async Task<HttpStatusCode> Webhook(UpdateContentRequestBody body)
{
var NO_ERROR = 0;
try
{
if (string.IsNullOrEmpty(SessionToken))
{
// This registers my service.
var registerConector = ConectorOSCCApi.RegisterConector();
if (respostaRegistrarConector.ErrorCode != NO_ERROR)
{
throw new Exception();
}
SessionToken = registerConector.SessionToken;
}
ConectorApi.KeepAliveRequest(SessionToken);
RepeatKeepAlive();
ProccessDataAndSendResponseRequest(body);
return HttpStatusCode.OK;
}
catch (Exception e)
{
SessionToken = "";
return HttpStatusCode.InternalServerError;
}
I want the method to register the service to run without the need of a call to "connector/webhook", but the rest of the processing and response to only happens when such a call is received. How can I do that?
EDIT:
My code is inside a ASP.NET Web Application.
I am using .NET Framework 4.5 and hosting my web application on IIS.

This should do it for you :)
public class Controller : ApiController
{
static string _sessionToken = "";
static string SessionToken
{
get
{
if (string.IsNullOrEmpty(_sessionToken))
{
InitToken();
}
return _sessionToken
}
}
void InitToken()
{
if (string.IsNullOrEmpty(_sessionToken))
{
// This registers my service.
var registerConector = ConectorOSCCApi.RegisterConector();
if (respostaRegistrarConector.ErrorCode != NO_ERROR)
{
throw new Exception();
}
_sessionToken = registerConector.SessionToken;
}
}
public Controller() : base()
{
InitToken();
// anything else
}
[HttpPost]
[Route("connector/webhook")]
public async Task<HttpStatusCode> Webhook(UpdateContentRequestBody body)
{
var NO_ERROR = 0;
try
{
ConectorApi.KeepAliveRequest(SessionToken);
RepeatKeepAlive();
ProccessDataAndSendResponseRequest(body);
return HttpStatusCode.OK;
}
catch (Exception e)
{
SessionToken = "";
return HttpStatusCode.InternalServerError;
}
}
}

You don't need to wait for a request to your service to request a token.
Prerequisites : make sure you know what error code you receive from the third party API if your token is no longer correct.
When your API initializes, you will have a method available, ApplicationStart or something else in Startup.cs, depending on version, setup etc. Use that method to request the token from the third party API. Cache the token in the application level cache.
An example of caching can be found here: Caching Data in Web API
When your application receives a request, grab the token from the cache and issue the call to the third part API. If everything works, happy days. If it fails with token issue error code, then re-issue the token request and try again this time with the fresh token. Replace the cached token with the new one.
So basically, keep using a token until it fails, then automatically request a new one and update it. This way you don't need to be there to request the token manually.
You could wrap up this token logic into a service class so you don't have a lot to do in the endpoints.

Cannot access child value on JValue in Azure Mobile App

I recently implemented custom authentication with Azure Mobile App - All the server side works fine and also my web application which is using that mobile app service is working fine. I tested the server-side in details with POSTMAN and with different scenarios, everything works fine until I try to LoginAsync on Xamarin.
When I pass email and password in POSTMAN, I get the following response as a clear indication that it is working
but when I send a request from my app using LoginAsync I get the following error.
Cannot access child value on Newtonsoft.Json.Linq.JValue
My code to send request is fairly simple as following
public async Task<bool> Authenticate()
{
string username = "todo#gmail.com";
string password = "todo";
string message = string.Empty;
var success = false;
var credentials = new JObject
{
["email"] = username,
["password"] = password
};
try
{
MobileServiceUser user = await client.LoginAsync("CustomAuth", credentials);
if (user != null)
{
success = true;
CreateAndShowDialog("OK", "Auth");
}
}
catch (Exception ex)
{
CreateAndShowDialog(ex, "Auth Error");
}
return success;
}
where I am calling it as follows
private MobileServiceClient client;
client = new MobileServiceClient(applicationURL);
await Authenticate();
Any idea why I am getting Cannot access child value on Newtonsoft.Json.Linq.JValue error?
Cheers
EDIT POST
As a workaround, I am temporarily using InvokeApiAsync with JObject.FromObject instead of LoginAsync
await client.InvokeApiAsync("/.auth/login/CustomAuth", JObject.FromObject(credentials), HttpMethod.Post, null);
I am still not sure why LoginAsync does not work - Until I find a solution I will keep using InvokdeApiAsync as a workaround

AFAIK, your initialization for credentials is correct. For the below error:
Cannot access child value on Newtonsoft.Json.Linq.JValue
I checked your testing result via POSTMAN and found that you did not return userId to your client. The essential properties returned to your client would look like as follows:
{
"authenticationToken":"***",
"user":{
"userId":"***"
}
}
When using MobileServiceClient.LoginAsync, the client SDK would internally invoke LoginAsync() method under MobileServiceAuthentication.cs as follows:
JToken authToken = JToken.Parse(response);
// Get the Mobile Services auth token and user data
this.Client.CurrentUser = new MobileServiceUser((string)authToken["user"]["userId"]);
this.Client.CurrentUser.MobileServiceAuthenticationToken = (string)authToken[LoginAsyncAuthenticationTokenKey];
You would find that it would try to extract the userId property under user to construct the MobileServiceUser instance and assign to MobileServiceClient.CurrentUser.

Log in to SimpleMembership app using external SAML identity provider

I was tasked with adding logging via external service (using SAML 2.0) to an MVC app (.Net 4.5) that uses SimpleMembership. To be honest I'm not even sure where to start. From what I found on the internet there are few points to the problem. Most of the materials I found dealt with communication with the SAML identity provider (frequently written from scratch). However before I can reach that point I need to make sure I can actually integrate it with the SimpleMembership which we are using.
I suspect for starters I would need something like SAMLWebSecurity (akin to OAuthWebSecurity which we also use). I have found no such thing* on the internet which makes me believe it does not exist (though I wouldn't mind being wrong here). This makes me believe I would have to write it myself, but can I do that without have to write my own membership provider?
*I'm not sure what would be a correct way to call this static class.

I'd recommend that you upgrade to ASP.NET Identity and the OWIN Based authentication middleware. Then you can use Kentor.AuthServices middleware that works with ASP.NET Identity (except that the XSRF-guard has to be commented out until bug #127 has been resolved).
You could also use the SAML classes from Kentor.AuthServices if you have to stick with SimpleMembership, so that you don't have to implement SAML from scratch.
Disclaimer: I'm the author of Kentor.AuthServices, but since it's open source, I'm not making money on people using it.

After discussing it with a colleague I think I figured out the course of actions. Both OAuthWebSecurity and WebSecurity appear to be a part of SimpleMembership, so what I wrote in the question would indicate I want to write a custom membership or reverse engineer SimpleMembership to copy OAuthWebSecurity (which doesn't sound like a fun activity to have).
My best bet here is hijacking the OAuthWebSecurity, by writing a custom client (one which implements the IAuthenticationClient interface). Normally one registers various OAuth clients using OAuthWebSecurity's built in methods (like RegisterFacebookClient). But it is also possible to register those clients using OAuthWebSecurity.RegisterClient which accepts IAuthenticationClient. This way I should be able to add this SAML login without writing a custom membership provider and keep using SimpleMembership.
I managed to do this. Thankfully the identity provider wasn't extremely complicated so all I had to do was redirect to a certain address (I didn't even need to request assertion). After a successful login, the IDP "redirects" the user using POST to my site with the base64 encoded SAMLResponse attached. So all I had to do was to parse and validate the response. I placed the code for this in my custom client (implementing IAuthenticationClient interface).
public class mySAMLClient : IAuthenticationClient
{
// I store the IDP certificate in App_Data
// This can by actually skipped. See VerifyAuthentication for more details
private static X509Certificate2 certificate = null;
private X509Certificate2 Certificate
{
get
{
if (certificate == null)
{
certificate = new X509Certificate2(Path.Combine(HttpContext.Current.ApplicationInstance.Server.MapPath("~/App_Data"), "idp.cer"));
}
return certificate;
}
}
private string providerName;
public string ProviderName
{
get
{
return providerName;
}
}
public mySAMLClient()
{
// This probably should be provided as a parameter for the constructor, but in my case this is enough
providerName = "mySAML";
}
public void RequestAuthentication(HttpContextBase context, Uri returnUrl)
{
// Normally you would need to request assertion here, but in my case redirecting to certain address was enough
context.Response.Redirect("IDP login address");
}
public AuthenticationResult VerifyAuthentication(HttpContextBase context)
{
// For one reason or another I had to redirect my SAML callback (POST) to my OAUTH callback (GET)
// Since I needed to retain the POST data, I temporarily copied it to session
var response = context.Session["SAMLResponse"].ToString();
context.Session.Remove("SAMLResponse");
if (response == null)
{
throw new Exception("Missing SAML response!");
}
// Decode the response
response = Encoding.UTF8.GetString(Convert.FromBase64String(response));
// Parse the response
var assertion = new XmlDocument { PreserveWhitespace = true };
assertion.LoadXml(response);
//Validating signature based on: http://stackoverflow.com/a/6139044
// adding namespaces
var ns = new XmlNamespaceManager(assertion.NameTable);
ns.AddNamespace("samlp", #"urn:oasis:names:tc:SAML:2.0:protocol");
ns.AddNamespace("saml", #"urn:oasis:names:tc:SAML:2.0:assertion");
ns.AddNamespace("ds", #"http://www.w3.org/2000/09/xmldsig#");
// extracting necessary nodes
var responseNode = assertion.SelectSingleNode("/samlp:Response", ns);
var assertionNode = responseNode.SelectSingleNode("saml:Assertion", ns);
var signNode = responseNode.SelectSingleNode("ds:Signature", ns);
// loading the signature node
var signedXml = new SignedXml(assertion.DocumentElement);
signedXml.LoadXml(signNode as XmlElement);
// You can extract the certificate from the response, but then you would have to check if the issuer is correct
// Here we only check if the signature is valid. Since I have a copy of the certificate, I know who the issuer is
// So if the signature is valid I then it was sent from the right place (probably).
//var certificateNode = signNode.SelectSingleNode(".//ds:X509Certificate", ns);
//var Certificate = new X509Certificate2(System.Text.Encoding.UTF8.GetBytes(certificateNode.InnerText));
// checking signature
bool isSigned = signedXml.CheckSignature(Certificate, true);
if (!isSigned)
{
throw new Exception("Certificate and signature mismatch!");
}
// If you extracted the signature, you would check the issuer here
// Here is the validation of the response
// Some of this might be unnecessary in your case, or might not be enough (especially if you plan to use SAML for more than just SSO)
var statusNode = responseNode.SelectSingleNode("samlp:Status/samlp:StatusCode", ns);
if (statusNode.Attributes["Value"].Value != "urn:oasis:names:tc:SAML:2.0:status:Success")
{
throw new Exception("Incorrect status code!");
}
var conditionsNode = assertionNode.SelectSingleNode("saml:Conditions", ns);
var audienceNode = conditionsNode.SelectSingleNode("//saml:Audience", ns);
if (audienceNode.InnerText != "Name of your app on the IDP")
{
throw new Exception("Incorrect audience!");
}
var startDate = XmlConvert.ToDateTime(conditionsNode.Attributes["NotBefore"].Value, XmlDateTimeSerializationMode.Utc);
var endDate = XmlConvert.ToDateTime(conditionsNode.Attributes["NotOnOrAfter"].Value, XmlDateTimeSerializationMode.Utc);
if (DateTime.UtcNow < startDate || DateTime.UtcNow > endDate)
{
throw new Exception("Conditions are not met!");
}
var fields = new Dictionary<string, string>();
var userId = assertionNode.SelectSingleNode("//saml:NameID", ns).InnerText;
var userName = assertionNode.SelectSingleNode("//saml:Attribute[#Name=\"urn:oid:1.2.840.113549.1.9.1\"]/saml:AttributeValue", ns).InnerText;
// you can also extract some of the other fields in similar fashion
var result = new AuthenticationResult(true, ProviderName, userId, userName, fields);
return result;
}
}
Then I just registered my client in App_Start\AuthConfig.cs using OAuthWebSecurity.RegisterClient and then I could reuse my existing external login code (which was originally made for OAUTH). For various reasons my SAML callback was a different action than my OAUTH callback. The code for this action was more or less this:
[AllowAnonymous]
public ActionResult Saml(string returnUrl)
{
Session["SAMLResponse"] = Request.Form["SAMLResponse"];
return Redirect(Url.Action("ExternalLoginCallback") + "?__provider__=mySAML");
}
Additionally OAuthWebSecurity.VerifyAuthentication didn't work with my client too well, so I had to conditionally run my own verification in the OAUTH callback.
AuthenticationResult result = null;
if (Request.QueryString["__provider__"] == "mySAML")
{
result = new mySAMLClient().VerifyAuthentication(HttpContext);
}
else
{
// use OAuthWebSecurity.VerifyAuthentication
}
This probably all looks very weird and might differ greatly in case of your IDP, but thanks to this I was able to reuse most of the existing code for handling external accounts.

Retrieve instagram access token on page load

I want to show my user feed on my website and what I intend to do is to authenticate my own user account each time a user visits the page, and in that way buypass that the user have to log in to his instagram account.
My problem is that I'm having a hard time retrieving the instagram access token through a HttpWebRequest..
See the following NON working code sample:
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://api.instagram.com/oauth/authorize?client_id=xxxxxxxxxxxxxxxxxxxxxx&redirect_uri=http://mywebsite.com&response_type=token");
request.Method = "POST";
request.AllowAutoRedirect = false;
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
string redirectUrl = response.ResponseUri.ToString();
HttpContext.Current.Response.Write(redirectUrl);
HttpContext.Current.Response.End();
If I paste the url in my browser I get a redirect to http://mysite.com/#access_token=xxxxxxxxxxxxxx and everything seems fine, but when I try to execute the code above, I can't retrieve the correct uri due to some in between redirects before the final url.
Any help would be much appriciated..

I recommend you to use Instasharp library. InstaSharp is a C# library that wraps the Instagram API and makes it easy to write applications with Instagram data. It has a very easy method to get access token for a user. Check its API.

Unfortunately the documentation for Instasharp currently provided has a few errors. I.e. The documentation says OAuthInfo, when such a class does not exist.
Here is some code that works for me.
Notice you don't seem to need to pass a User Object at all (not sure why you would need to anyway)
Also note, that the authenticated and non authenticated methods allow you pass different params, count being the most important one. I've noticed that regardless of the count you pass, an arbitrary number of results is returned, e.g. 33 for authenticated and 13 for authenticated for the same search term. InstagramResult is my wrapper class for the object and Config holds the InstagramAuthorisationModel and InstagramAuthorisationModel holds the static keys created when signing up for a developer account.
public class InstagramService : IInstagramService
...
public InstagramConfig Config
{
get{return new InstagramConfig("https://api.instagram.com/v1", "https://api.instagram.com/oauth", InstagramAuthorisationModel.ApplicationId, InstagramAuthorisationModel.Secret, InstagramAuthorisationModel.RedirectUri);}
}
private AuthInfo UserAuthInfo()
{
return new AuthInfo()
{
// User =new UserInfo(){},
Access_Token = GetInstagramAccessToken()
};
}
public string GetInstagramAccessToken()
{
return _socialMediaRepository.GetInstagramAccessToken(_userApiKey);
}
public List<InstagramResult> Search(string searchTag, int count)
{
var auth = UserAuthInfo();
var tags = new InstaSharp.Endpoints.Tags.Authenticated(Config, auth);
var searchresult = tags.Recent(searchTag);
return searchresult.Data.Select(media => new InstagramResult()
{
Media = media,
image = media.Images.LowResolution.Url
})
.ToList();
}
..