Asp.Net core Swashbuckle set operationId

There are 2 other options without having to write any extra code or add extra dependency like Swashbuckle.AspNetCore.Annotations

Option 1: Convention based - SwaggerGen has an option to set CustomOperationIds. So you can simply set it to use ControllerName_HttpMethod like this:

services.AddSwaggerGen(c =>
{
    c.CustomOperationIds(e => $"{e.ActionDescriptor.RouteValues["controller"]}_{e.HttpMethod}");
    c.SwaggerDoc("v1", new Info { Title = "Test API", Version = "v1" });
});

This will add operationIds to all your methods, following ControllerName_HttpMethod convention.

Option 2: ActionFilter/Attribute based - you can configure each Action method (as you'd do with SwaggerOperation action filter by simple adding a Name property to your HTTP verb action filter like this:

[HttpPost(Name="Post_Person")]
[ProducesResponseType(200)]
[ProducesResponseType(400)]
[ProducesResponseType(500)]
public async Task<ActionResult<Response>> PostAsync([FromBody]Request request)
{
    Response result = await _context.PostAsync(request);
    return Ok(result);
}

This works exactly like [SwaggerOperation(OperationId = "Post_Person")] but without the need of EnableAnnotations

You can enable annotation on swagger with the Swashbuckle.AspNetCore.Annotations NuGet package. (https://github.com/domaindrivendev/Swashbuckle.AspNetCore/blob/master/README.md#swashbuckleaspnetcoreannotations)

Once annotations have been enabled, you can enrich the generated Operation metadata by decorating actions with a SwaggerOperationAttribute.

[HttpPost]

[SwaggerOperation(
    Summary = "Creates a new product",
    Description = "Requires admin privileges",
    OperationId = "CreateProduct",
    Tags = new[] { "Purchase", "Products" }
)]
public IActionResult Create([FromBody]Product product)

Adding a Name parameter to [HttpGet]/[HttpPost] fails with an exception in the most recent version, but putting a Name parameter on the Route attribute seems to work:

/// <summary>
/// Get all devices
/// </summary>
[Route("devices", Name = "GetAllDevices")]
[Authorize]
[HttpGet]
[Produces(typeof(Device[]))]
public async Task<IActionResult> GetAllDevices() { ...}

You can also generate the operation id based on the action name which is the method name, I found this handy when generating the API client.

services.AddSwaggerGen(c =>
{
    c.CustomOperationIds(e => $"{e.ActionDescriptor.RouteValues["action"]}");
    c.SwaggerDoc("v1", new Info { Title = "Test API", Version = "v1" });
});