Authenticating via RESTful API service

Question

When using Postman to connect and authenticate to the actual RESTful API service through Postman, I keep getting the same problem:

{
"Message": "An error has occurred.",
"ExceptionMessage": "Object reference not set to an instance of an object.",
"ExceptionType": "System.NullReferenceException",
"StackTrace": " 
    at Sitecore.Services.Infrastructure.Sitecore.Controllers.AuthenticationServiceApiController.Login(UserCredentials credentials)
    at lambda_method(Closure , Object , Object[] )
    at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ActionExecutor.c__DisplayClass6_1.b__3(Object instance, Object[] methodParameters)
    at System.Web.Http.Controllers.ReflectedHttpActionDescriptor.ExecuteAsync(HttpControllerContext controllerContext, IDictionary`2 arguments, CancellationToken cancellationToken)
    --- End of stack trace from previous location where exception was thrown --
.......>
}

With these details:

POST /sitecore/api/ssc/auth/login HTTP/1.1
Host: MY-HOST-ENVIRONMENT
Content-Type: application/json
User-Agent: PostmanRuntime/7.16.3
Accept: */*
Cache-Control: no-cache
Postman-Token: 1b4ffd83-f627-4955-852b-971d67c5fa72,fd32dcbe-c494-4c06-8db1-b7119005424d
Accept-Encoding: gzip, deflate
Content-Length: 87
Connection: keep-alive
cache-control: no-cache

{
“domain”:”sitecore”,
“username”:”admin”,
“password”:”b”
}

I haven't made any specific changes in the Sitecore.Services.Client.config file of my instance and have tried the same on both a local and remote SC9.1 as well as an 8.2 version but in all instances I got the same problem.

Also, when changing the setting for: <setting name="Sitecore.Services.AllowAnonymousUser" value="false" /> then I am able to execute the actual retrieval of an item's details with calls such as: /sitecore/API/ssc/item/{10083CA0-5093-4D67-99DB-2579ABB421D3}

I used these information sources:

• https://doc.sitecore.com/developers/90/sitecore-experience-management/en/sitecore-services-client.html
• https://therelentlessfrontend.com/2018/02/11/sitecore-postman-a-quick-starter-guide/

Additional question is on the information I found online concerning token based authorization, still somewhat unclear as to where this fits in to the entire story.

Answer 1

Try to add credentials to the request body:

Tip: You may switch to the Bulk Edit mode (on the right) and inject data as text:

domain:sitecore
userName:admin
password:b

Answer 2

As it turns out, for some reason, the values typed in Postman got the wrong Hyphens...

-”- instead of -"-

And the nullreference then follows suit as the AuthenticationController can't figure out the required parameters