ASP.net 5 Web API Post CreatedAtRoute always returns 500 Internal Server Error - asp.net-web-api

Question

The database works. It does actually insert the new record, but when I use CreatedAtRoute(), I always get a 500 back from the client. Why?
My controller's Get:
[Route("api/[controller]")]
public class IngredientController : Controller
{
private SimpleCookbookDbContext db { get; set; }
public IngredientController(SimpleCookbookDbContext context)
{
db = context;
}
// GET: api/values
[HttpGet]
public async Task<IEnumerable<Ingredient>> Get()
{
return await db.Ingredients.ToListAsync();
}
// GET api/values/5
[HttpGet("{id}", Name = "GetIngredient")]
public async Task<Ingredient> Get(int id)
{
return await db.Ingredients.SingleOrDefaultAsync(i => i.Id == id);
}
[HttpPost]
public async Task<IActionResult> Post([FromBody]Ingredient ingredient)
{
try
{
var res = await IM.CreateAsync(ingredient);
if (!res.Success)
{
return HttpBadRequest(res.Errors);
}
}
catch(Exception)
{
return new HttpStatusCodeResult((int)HttpStatusCode.InternalServerError);
}
return CreatedAtRoute("GetIngredient", new { controller="Ingredient", id = ingredient.Id });
}
}
I tried debugging this. Yes, it would return the HttpBadRequest if the ingredient I'm trying to insert already exists.
I tried putting a breakpoint inside the catch block, and I'm not getting there, so I assume there was no error from the database.
The record does get inserted to the database. I do get to the line return CreatedAtRoute(...); but I get a 500 back. (I set a breakpoint there, too).
Now, I'm using fiddler. My request is this:
POST /api/ingredient HTTP/1.1
Host: localhost:55303
Content-Type: application/json;charset=utf-8
{"id":0, "name": "rosemary", "description": "rosemary"}
I also removed the double quotes on the property names, and I still get the same 500.
I do have camel-casing resolved at the Startup:
services.AddMvc().AddJsonOptions(options => {
options.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
});
I think I showed all relevant code. If you need more, please let me know.
UPDATE
CreatedAtRoute has an overload taking in three parameters:
return CreatedAtRoute("GetIngredient", new { controller="Ingredient", id = ingredient.Id }, ingredient);
The last parameter is an object, which you could create dynamically or pass back your entire entity, depending on what you want to expose back.
It's strange how there's a 2-parameter variant that would result in a strange 500 response.