Is there a way to remove the parentheses from functions?

[cyril-iselin]

I define a function like this:

config.Collection.Action("MyAction") ....

The result is a route like

MyEntity.MyAction**()**

Before 8.0 with the same configuration the () wasn't part of the route. Can I remove them ?

[xuzhg]

@cyril-iselin

In 8.0,

• A route for an Edm action is not parenthesis in the route template.

• A route for an Edm function should have a parenthesis in the route template, even this function doesn't have parameters.

So, I can't understand where to remove parenthesis for Action.
Can you share more details?

[cyril-iselin]

Hello @xuzhg . Thanks for your answer.

A route for an Edm function should have a parenthesis in the route template, even this function doesn't have parameters.

So that's a breaking change for 8.0 ? Is there an option to make parenthesis optional on functions without parameters?
(for not breaking old routes)

[xuzhg]

@cyril-iselin Are you sure in the 7.x, parenthesis for empty parameter function is not required? In my memory, it's required.

The reason why i ask this question is because your sample is using Action, not using Function.

Would you please help check the Function?

[cyril-iselin]

Thanks for your answer xuzhg. I'm still (since years) confused about functions and actions, I provide some sample:

OData 8 declaration

  [HttpGet("WhatEver")]
  [ODataApiLoginAuthorize]
  public DateTime WhatEver()
  {
     return m_service.WhatEver<TEntity>();
  }

Odata 7 declaration:

 [ODataRoute("WhatEver")]
 [ODataApiLoginAuthorize]
 [HttpGet]
 public DateTime WhatEver()
 {
       return m_service.WhatEver<TEntity>();
 }

Configuration (both 7 & 8)

builder.EntityType<TDto>().Collection.Function("WhatEver").Returns<DateTime>();

Route in Odata 7

odata/v2/Entity/WhatEver

Route in Odata 8

odata/v2/Entity/WhatEver()

So yes, in 7.X parenthesis for empty parameter function was not present. I hope there is an option for 8.0 to enable the same behaiovir because of backwards compatibility....

[xuzhg]

@cyril-iselin The latest has a option to enable the non-parenthesis for empty parameter function.
https://github.com/OData/AspNetCoreOData/blob/master/src/Microsoft.AspNetCore.OData/Routing/ODataRouteOptions.cs#L108

Would you please help to check whether it is working or not?

[xuzhg]

@cyril-iselin It's available in the latest rc3 version, please try and let me know any other questions.

[mlafleur]

@xuzhg This is still an issue with bound functions. I suspect this is due to the ParameterMappings.Count returning 1 due to the required bindingParameter.

if (ParameterMappings.Count == 0 && options.EnableNonParenthesisForEmptyParameterFunction)

The spec is admittedly vague in this area. In particular, these two statements could be read as contradictory:

The value for the binding parameter is the value of the resource identified by the URL prior to appending the function name, and additional parameter values are specified using inline parameter syntax.

Services MAY support omitting the parentheses when invoking a function import with no parameters, but for maximum interoperability MUST also support invoking the function import with empty parentheses.

My interpretation is that since a function with only a binding parameter is called with empty parentheses, the parentheses are optional.

[buchatsky]

EnableNonParenthesisForEmptyParameterFunction does not work as expected. If it is true it not only enables non-parenthesis function calls but also disables with-parenthesis ones. It makes a problem when different odata clients are used