add gatsby example

[djskinner]

Goal

To demonstrate how to integrate BugSnag with Gatsby projects

Design

Focus on browser error tracking as most of the Gatsby usage is expected to be SSG pages

Testing

gatsby develop:

• error in dashboard from the exception in useEffect
• error in dashboard from the Bad button handler useCallback
• error in dashboard from the bad button error thrown during render

gatsby build && gatsby serve:

• error in dashboard from the exception in useEffect
• error in dashboard from the Bad button handler useCallback
• error in dashboard with 'react' metadata tab from the bad button error thrown during render

[github-actions]

@bugsnag/browser bundle size diff

	Minified	Minfied + Gzipped
Before	43.67 kB	13.40 kB
After	43.67 kB	13.40 kB
±	No change	No change

code coverage diff

<temporarily disabled>

Generated by 🚫 dangerJS against 27d2bc0

[gareththackeray]

What are gatsby-node.js and gatsby-ssr.js ?

[djskinner]

See https://www.gatsbyjs.com/docs/reference/config-files/gatsby-node/ and https://www.gatsbyjs.com/docs/reference/config-files/gatsby-ssr/ respectively

This is just the standard tsconfig that comes when starting a new Gatsby project. gatsby-node.js and gatsby-ssr.js and gatsby-browser.js are optional files

[imjoehaines]

This can use Bugsnag.isStarted instead of keeping track manually

Suggested change

	/**
	* With `gatsby develop` wrapRootElement is called before onClientEntry and then again afterwards.
	* However, `gatsby serve` onClientEntry is called, followed by wrapRootElement. So we need this
	* extra state to deal with the difference in behavior.
	*/
	let bugsnagStarted = false
	export const onClientEntry = () => {
	if (bugsnagStarted) {
	return
	}
	Bugsnag.start(bugsnagConfig)
	bugsnagStarted = true
	}
	export const onClientEntry = () => {
	if (Bugsnag.isStarted) {
	return
	}
	Bugsnag.start(bugsnagConfig)
	}

[imjoehaines]

Suggested change

	if (!bugsnagStarted) {
	Bugsnag.start(bugsnagConfig)
	bugsnagStarted = true
	}
	if (!Bugsnag.isStarted) {
	Bugsnag.start(bugsnagConfig)
	}