My only comment would be that the Node representation is an instance (the underline under the node type name) whereas the component is a classifier (no underline in the name). You might want to make the component an instance too, if you are modelling an actual deployment, or make the node a type if you are modelling a logical deployment design.
I've put together an example. You'll have to excuse it though -- the syntax of the instances needs underlines and I'm not sure why that's not displaying. But hopefully you get the picture (no pun intended). [Edit -- fixed that!].
Regarding your query about the NodeJs part of this. That would be a separate node, with a NodeJS component on it. The Web Client is the browser machine, or possibly the browser itself if you want to argue that, which is where your JS is executing. You might want to go in to more detail and add these for clarity.
