Add endpoint for refresh

[PepperTeasdale]

This is only active if you actively enable via an environment variable. This is following up on #3054 per @KyleAMathews 's idea for a #dark-deploy

[gatsbybot]

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[KyleAMathews]

Like the hashtag :-) #darkdeploy

Thanks!

[Jrousell]

Hi, this is exactly what I've been looking for - the ability to force a refresh of the fetched content, whilst in gatsby develop. Is there a doc, example or anything on how to set this up, which env vars to set etc... Many thanks

[Jrousell]

Got it working and it's awesome - many thanks.

[tlvenn]

@Jrousell any chance you could document how you got this working ? Thanks in advance !

[nik-s]

@tlvenn you need to enable the ENABLE_GATSBY_REFRESH_ENDPOINT env variable when you start the development server, for example:

export ENABLE_GATSBY_REFRESH_ENDPOINT=true && gatsby develop

Then you make a POST request to the __refresh endpoint in order to refresh data:

curl -X POST http://localhost:8000/__refresh

[ThiagoMiranda]

@nik-s is there any indication that:
1- I´m deploying in ENABLE_GATSBY_REFRESH_ENDPOINT mode true
2- The POST was succesfull? I´m not getting any response from the server

[richhiggins]

I've been trying this - using ngrok locally, finding it to be unreliable so far. sometimes the update is fine, sometimes I end up with errors usually something along the lines of TypeError: Cannot read property 'name' of undefined. restarting dev resolves this, sometimes removing the reference from the JSX, saving, and then putting back also resolves this. anyone had similar experience?