[API Proposal]: Add Parallel.InvokeAsync

[bill-poole]

Background and motivation

Parallel.Invoke currently provides for concurrently executing a set of Actions, but does not provide for executing a set of async actions (Func<CancellationToken, ValueTask>). I have found a frequent need to concurrently execute a set of async actions, where if any action fails, all other actions are cancelled and the exception of the failing action is thrown. i.e., similar behavior is required that is provided by Parallel.ForEachAsync, but where ForEachAsync executes a single function for a collection of inputs, Parallel.InvokeAsync would execute a collection of async actions.

API Proposal

namespace System.Threading.Tasks

public static class Parallel
{
    public static Task InvokeAsync(params Func<CancellationToken, ValueTask>[] actions);

    public static Task InvokeAsync(CancellationToken cancellationToken, params Func<CancellationToken, ValueTask>[] actions);

    public static Task InvokeAsync(ParallelOptions parallelOptions, params Func<CancellationToken, ValueTask> actions);
}

API Usage

await Parallel.InvokeAsync(
  async ct => obj.Id = new(obj.Id.ExternalId, internalId: await idMapper.GetInternalId(obj.Id.ExternalId, ct)),
  async ct => obj.ParentId = new(obj.Id.ExternalId, internalId: await idMapper.GetInternalId(obj.ParentId.ExternalId, ct)),
  async ct => obj.OrderId = new(obj.Id.ExternalId, internalId: await idMapper.GetInternalId(obj.OrderId.ExternalId, ct)),
  async ct => obj.AssignmentId = new(obj.Id.ExternalId, internalId: await idMapper.GetInternalId(obj.AssignmentId.ExternalId, ct)));

Alternative Designs

No response

Risks

No response

[dotnet-policy-service]

Tagging subscribers to this area: @dotnet/area-system-threading-tasks
See info in area-owners.md if you want to be subscribed.