Add createRedirects action and Netlify support

[bvaughn]

This is done in support of the new React website.

Example usage

Temporary redirect

createRedirect({
  fromPath: '/some/old/path',
  toPath: '/some/new/path',
});

Permanent redirect

createRedirect({
  fromPath: '/some/old/path',
  toPath: '/some/new/path',
  isPermanent: true,
});

[KyleAMathews]

@pk-nb hey! we added support for redirects to your netlify plugin. In so doing, the "netlify-headers" title didn't make as much sense so we renamed it to gatsby-plugin-netlify to reflect its more generic nature.

[gatsbybot]

Deploy preview ready!

Built with commit 9020566

https://deploy-preview-2185--gatsbygram.netlify.com

[KyleAMathews]

Hmm just realized we will need to do client side redirects still in production. E.g. handling your blog redirect use case.

[bvaughn]

Hmm just realized we will need to do client side redirects still in production.

You mean for non-Netlify use cases?

[bvaughn]

Rats! I tried integrating with the new plugin in facebook/react/pull/10771 and the redirect doesn't seem to work.

https://deploy-preview-10771--reactjs.netlify.com/blog.html

I'll look into it. 😦

Edit 1: Looks like public/_redirects isn't actually being written on a clean test. Whoops! I know we both saw this working yesterday so I'm not sure what's up yet. Will continue digging.

Edit 2: Based on my console logging, it looks like gatsby-plugin-netlify isn't actually running. I think that's because only the source is published (no build) so there's nothing to execute. (eg there should be a gatsby-node.js file in the root here, right? https://unpkg.com/gatsby-plugin-netlify@1.0.2/)

[bvaughn]

Looks like a bad version of gatsby-plugin-netlify was published (without any build source). Confirmed that running yarn install & yarn build in node_modules/gatsby-plugin-netlify resolves the issue for me locally.

[bvaughn]

Maybe you can re-publish after building- let me know and I'll update the version and confirm the fix on my end.

[pk-nb]

Cool, thanks for letting me know!

[pk-nb]

Maybe this could be a promise.all, so they can run in parallel instead of series?

[pk-nb]

Maybe we could add a plugin option to disable this as well?

[bvaughn]

Is there any harm in writing an empty _redirects file? Or are you concerned that we might override an existing one? (Guess it would be worth checking to see if we should append vs write.)

[pk-nb]

Right—someone might want to make one by hand through the static folder rather than go through generation in this plugin.

[bvaughn]

I'll create a follow-up PR.

[bvaughn]

Done in PR #2191

[KyleAMathews]

Looks like a bad version of gatsby-plugin-netlify was published

Yeah, it's missing a .npmignore file. Adding and publishing.

[KyleAMathews]

Yeah showing up now https://unpkg.com/gatsby-plugin-netlify@1.0.3/gatsby-node.js

[bvaughn]

Thanks Kyle!

[sebastienfi]

Thanks @bvaughn for this feature, we can now create plugins for every hosting software.