TypeError: Cannot read property 'address' of null

I’ve started getting this error when running gatsby develop:

error UNHANDLED REJECTION


  TypeError: Cannot read property 'address' of null

  - develop.js:371 _callee3$
    [StateOfJS]/[gatsby]/dist/commands/develop.js:371:38

  - next_tick.js:131 _combinedTickCallback
    internal/process/next_tick.js:131:7

  - next_tick.js:180 process._tickCallback
    internal/process/next_tick.js:180:9

I’m on Mac OS High Sierra with Node 8.9.1. I first got the error while using Node 9 so I downgraded and the error went away, but I noticed that hot module reloading wasn’t working. From reading #864 I got the idea to try gatsby develop --host localhost --port 8000 instead of gatsby develop, but then that triggered the address error again.

I’m not sure what’s going on exactly… Could it be related to my own config somehow?

[sebastienfi]

With the latest version atm of Gatsby, Gatsby-cli, running gatsby develop produces : On Windows, a link to localhost is generated, HMR is working, no CORS issue. On Mac, a link to locahost is generated, HMR is broken, CORS issues are showing. After launching the site this way, on Mac if you navigate to 0.0.0.0:8000 then everything works and no CORS.

My 2 cents on this : localhost is more widely supported, and the fact that 0.0.0.0 doesn’t exists on Windows, makes localhost a better candidate in my opinion.

[yeskunall]

You’re absolutely right. I guess it’s my fault for not looking at the whole thread more carefully. It does work with gatsby@latest. I’d like to point out however, that gatsby-starter-blog is still using v1.9.118, which is why I got that error above. If you’d like, I can make a PR to fix that issue over at gatsbyjs/gatsby-starter-blog!