Azure Functions and Web Job Tools for Visual Studio 2017 enables you to create, debug, and publish Azure Functions and Web Job projects using Visual Studio 2017.
See Azure Functions repository.
*Note: The version of the extension downloaded here on the Marketplace can only be used to update an extension that is already installed on your Visual Studio instance. If you do not already have the extension installed, you will need to launch the Visual Studio installer, modify your installation and select the Azure workload or "Cloud tools for web developers" optional component of the "ASP.NET and web development" workload. That will install the base version of the extension. Once you have the base version installed, you can update it with newer copies as they are released to the Marketplace.
For details and instructions, see the Azure Functions Tools for Visual Studio documentation