Add a FAQ entry for 'nbgitpuller link selecting profile options'

docs/faq.md

@@ -0,0 +1,23 @@
+# Frequently asked questions
+
+## Can I automatically tell JupyterHub what kind of server to start (node size, profile name, etc) as part of my nbgitpuller link?
+
+You can use Kubespawner's profile_list or ProfileSpawner to allow your
+end users to choose the resources (memory, cpu, GPUs, etc) they want before
+starting their server. Wouldn't it be nice if this information could be
+embedded in the nbgitpuller link, so this (often confusing) choice is made
+for your students?
+
+While it would indeed be very nice, this is currently not easy for two
+reasons:
+
+1. nbgitpuller is a Jupyter Server extension, and only runs _after_ the server
+   is started. It knows nothing about JupyterHub. So it can not influence the
+   options JupyterHub uses to start the server.
+2. There is UX complexity in what happens if the user clicks an nbgitpuller
+   link when a server is _already_ running, but with a different set of resource
+   requests / profile options. Do we shut that existing one down? Just error? Do
+   nothing? Many valid options, but takes a bunch of work.
+
+So while this workflow _is_ possible, it would most likely be done at the
+JupyterHub level to make it possible, rather than in nbgitpuller

docs/index.md

@@ -69,5 +69,6 @@ contributing
 topic/automatic-merging
 topic/url-options
 topic/repo-best-practices
+faq
 link
 ```