Does Spotify have a widget for Mac?

I've been thinking about adding widgets to my Mac but only Spotify.

Com has an API and I found out that it doesn't support Macs. Is there a widget for Mac using API available? I don't need anything like a streaming service so it's just a matter of the widget, not integration in another app/service.

No, you cannot add the Spotify widget from the Spotify website to your Mac (or any other website). To create a widget for your Mac, you would need to get started with Objective-C. This site will walk you through the process.

The problem is that Apple doesn't allow apps (except for a few, such as Spotify) to use the API in their SDK.

Does Spotify have a desktop app?

I don't see it.

How do you play from the phone? I tried searching the market, but couldn't find it. If the desktop app doesn't support play and stop functions, then I don't really want to install an app that will make me jump through hoops to use my music. Can anyone help with this or am I doomed to use crappy mobile apps?
If I remember correctly, Spotify for Desktop uses a web browser, not an application. This could be a problem if you want to run your own desktop web server as part of the setup, or even access it over HTTP without running a proxy on your local network.

So, what are you trying to accomplish? Have the Spotify streaming software play directly from your desktop? Otherwise, you'll need to either have Spotify running in the background using an application (eg, Spotify Connect), or stream the music to your Windows PC via Webhooks. There is also another approach, which I find more effective for streaming music to my Windows desktop: Windows Media Player. WMP has a Windows Desktop Gateway option, which you can turn on to stream audio from any streaming service directly to your desktop computer. WMP's Gateway feature works with any streaming service, and it's a nice solution if you're looking to simply have your personal music playlist or your favorite station played on the Internet, and the streaming media content is only for your desktop rather than being something you'd want to access on a phone or tablet.