Make A Web API in .net

https://www.sharpencode.com/article/WebApi/authentication-authorization/token-based-authentication

you just need to follow three steps

step 1. install these packages

install-package Microsoft.Owin.Host.SystemWeb
install-package Microsoft.Owin.Security.OAuth
install-package Microsoft.Owin.Cors

step 2. Add a class in your project and name it Startup.Cs

step 3. Add below code to your startup

public class Startup
{
public void Configuration(IAppBuilder app)
{
app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);
var myProvider = new AuthProvider();
OAuthAuthorizationServerOptions options = new OAuthAuthorizationServerOptions
{
AllowInsecureHttp = true,
TokenEndpointPath = new PathString("/token"),
AccessTokenExpireTimeSpan = TimeSpan.FromDays(1),
Provider = myProvider
};
app.UseOAuthAuthorizationServer(options);
app.UseOAuthBearerAuthentication(new OAuthBearerAuthenticationOptions());
HttpConfiguration config = new HttpConfiguration();
WebApiConfig.Register(config);
}

step 4. create AuthorizationServer as per your requirement like

public class AuthProvider: OAuthAuthorizationServerProvider
{
public override async Task ValidateClientAuthentication(OAuthValidateClientAuthenticationContext context)
{
context.Validated();
}
public override async Task GrantResourceOwnerCredentials(OAuthGrantResourceOwnerCredentialsContext context)
{
var identity = new ClaimsIdentity(context.Options.AuthenticationType);
if (context.UserName == "admin" && context.Password == "admin")
{
identity.AddClaim(new Claim(ClaimTypes.Role, "admin"));
identity.AddClaim(new Claim("username", "admin"));
identity.AddClaim(new Claim(ClaimTypes.Name, "Hi Admin"));
context.Validated(identity);
}
else if (context.UserName == "user" && context.Password == "user")
{
identity.AddClaim(new Claim(ClaimTypes.Role, "user"));
identity.AddClaim(new Claim("username", "user"));
identity.AddClaim(new Claim(ClaimTypes.Name, "Hi User"));
context.Validated(identity);
}
else
{
context.SetError("invalid_grant", "Provided username and password is incorrect");
return;
}
}
}

now you are all set just mark any method with Authorize attribute and run your application

to know more like what is OAuth and Owin read my article https://www.sharpencode.com/article/WebApi/authentication-authorization/token-based-authentication

4 Replies

Know the answer? Post it — somebody with the same question will find it here.

Sachin Singh5y ago
Accepted answer
https://www.sharpencode.com/article/WebApi/authentication-authorization/token-based-authentication
you just need to follow three steps

step 1. install these packages
install-package Microsoft.Owin.Host.SystemWeb
  install-package Microsoft.Owin.Security.OAuth
  install-package Microsoft.Owin.Cors
step 2. Add a class in your project and name it Startup.Cs
step 3. Add below code to your startup
public class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);
            var myProvider = new AuthProvider();
            OAuthAuthorizationServerOptions options = new OAuthAuthorizationServerOptions
            {
                AllowInsecureHttp = true,
                TokenEndpointPath = new PathString("/token"),
                AccessTokenExpireTimeSpan = TimeSpan.FromDays(1),
                Provider = myProvider
            };
            app.UseOAuthAuthorizationServer(options);
            app.UseOAuthBearerAuthentication(new OAuthBearerAuthenticationOptions());


            HttpConfiguration config = new HttpConfiguration();
            WebApiConfig.Register(config);
        }
step 4. create AuthorizationServer as per your requirement like
public class AuthProvider: OAuthAuthorizationServerProvider
    {
        public override async Task ValidateClientAuthentication(OAuthValidateClientAuthenticationContext context)
        {
            context.Validated();
        }
        public override async Task GrantResourceOwnerCredentials(OAuthGrantResourceOwnerCredentialsContext context)
        {
            var identity = new ClaimsIdentity(context.Options.AuthenticationType);
            if (context.UserName == "admin" && context.Password == "admin")
            {
                identity.AddClaim(new Claim(ClaimTypes.Role, "admin"));
                identity.AddClaim(new Claim("username", "admin"));
                identity.AddClaim(new Claim(ClaimTypes.Name, "Hi Admin"));
                context.Validated(identity);
            }
            else if (context.UserName == "user" && context.Password == "user")
            {
                identity.AddClaim(new Claim(ClaimTypes.Role, "user"));
                identity.AddClaim(new Claim("username", "user"));
                identity.AddClaim(new Claim(ClaimTypes.Name, "Hi User"));
                context.Validated(identity);
            }
            else
            {
                context.SetError("invalid_grant", "Provided username and password is incorrect");
                return;
            }
        }
    }
now you are all set just mark any method with Authorize attribute and run your application
to know more like what is OAuth and Owin read my article https://www.sharpencode.com/article/WebApi/authentication-authorization/token-based-authentication
+3
Asma Khalid5y ago
Look into this https://bit.ly/2Ka3NpZ

Mark answer as accpted if helpful

Thanks & Regards,
Asma Khalid

For More Visit: www.asmak9.com or www.bytezaar.com
+2
Mageshwaran R5y ago
https://www.dotnetcurry.com/aspnet/1223/secure-aspnet-web-api-using-tokens-owin-angularjs
+2
Piyush Pansuriya5y ago
Hi Sourabh,
Please go through the below URLs

https://www.dotnettricks.com/learn/webapi/token-based-authentication-in-aspnet-web-api

https://www.c-sharpcorner.com/UploadFile/ff2f08/token-based-authentication-using-Asp-Net-web-api-owin-and-i/

https://www.c-sharpcorner.com/article/web-ap/

https://developer.okta.com/blog/2018/02/01/secure-aspnetcore-webapi-token-auth
+3