chore(docs): added quick tip for using host option with gatsby develop

[gillkyle]

Description

Added a note based on a tip from a tweet that people seem to be enjoying: https://twitter.com/nelsreitz/status/1154131687950954497

Note: @pieh mentioned that 0.0.0.0 might not work on all platforms

[marcysutton]

@pieh do you have any specific platforms in mind that we could test? This worked for me on the Mac host side and I could view the IP address it output in the logs from the Windows VM side.

[KyleAMathews]

My memory was it doesn't work on windows. But perhaps it was Linux. You can search old issues. This used to be the default host for a bit

[gillkyle]

See also:

#171
#13128

Seems like maybe to specific of a tip to include based on discussion in those PRs.

[pieh]

I think we should do some testing and see if it's feasible to set 0.0.0.0 by default on platforms that are known to be working.

But in meantime I don't see harm with getting this one in?

[marcysutton]

I think these instructions would help illustrate usage–where otherwise the list of options aren't necessarily motivated by use cases. We could add a note about platform inconsistencies to give people a heads up?

[pieh]

I just did some tests with few platforms: Mac OS / Windows / Linux (Ubuntu). Windows and Linux were in virtual machines.

I was running gatsby develop -H 0.0.0.0 on each platform and trying to access development server on all platforms. Using Chrome on Mac OS and Windows, using Firefox on Linux.

I was checking:

• Initial load
• Hot webpack update (code change)
• Hot data update (content change)

In my setup things worked in all possible combinations when using actual IP addresses (or localhost:8000). Only thing that didn't work is trying to visit 0.0.0.0:8000 on Windows (works on Linux + Mac OS) - so to me it seems like we could try default to using 0.0.0.0 and instead just print out localhost for Windows as local URL (and maybe other platforms)

[sidharthachatterjee]

Looks good to ship! Thank you so much @gillkyle 🥇