Exploration for Server-side Rendering

[pdamoc]

@kevinyank

If the Elm runtime were going to attempt to pick a sensible moment to declare the view “stable”, I’d say it would be the first view after all of the commands triggered by init have run, the resulting updates processed, and the first view after that rendered. But even that would be full of edge-cases.

As far as I see, there are 2 things that need to happen:

1. A way to do the server sider render
2. A new way to initialize the Elm app

The simplest model that comes to my mind for the server-side render is a Task that produces a String that is the rendered html. Alternatively it could produce the model and have the conversion to String happen automatically. All the commands that end up in init would have to be converted to a chain of tasks in order for this to work. I’m expecting that most of the init code could be converted to a Task.

The initialization part is a little bit trickier. I cannot figure out how to do it without adding yet another parameter to the Program type. In essence, the init needs to receive a new data type that would represent the payload to a message that would put the initial model in the “after the initial update” state.