Deploy with attribute

To deploy with pure command line argument is not convenient. I think we should have ability to just specified attribute to function we want to deployed and deploy command would just use reflection to specified other arguments

Instead of

gcloud functions deploy configuration-example \
  --runtime dotnet3 \
  --trigger-http \
  --allow-unauthenticated \
  --entry-point Google.Cloud.Functions.Examples.Configuration.Function

I wish we could just

namespace Google.Cloud.Functions.Examples.Configuration
{
    public class Function : IHttpFunction
    {
        private readonly DatabaseService _database;

        public Function(DatabaseService database) =>
            _database = database;

        [HttpTrigger("configuration-example",null,null)] // member and role as last two argument, be null for --allow-unauthenticated
        public async Task HandleAsync(HttpContext context)
        {
            await context.Response.WriteAsync($"Retrieving data from instance '{_database.Instance}', database '{_database.Database}'");
        }
    }
}

then

gcloud functions deploy --runtime dotnet3 \
  --entry-point Google.Cloud.Functions.Examples.Configuration.Function

And we could just drop entry point to deploy the whole file with every function specified in that file

gcloud functions deploy --runtime dotnet3

[jskeet]

I think it would be clearer to rewrite it in a non-dotnet-specific way to start with. Bear in mind that many of the readers of issues in that repo won’t have any .NET experience, so may not understand the example… whereas if you write it up in a technology-neutral way, I think it will be a far better feature request.

[jskeet]

(Sorry, the reopening was inadvertent - I still believe that raising an issue in https://github.com/GoogleCloudPlatform/functions-framework is a better approach.)