## What's wrong
This problem is specific to errors that happen on the client _after_ the initial mounting of the component. (The router has special logic to handle exceptions thrown in `getInitialProps` during a client-side navigation, and I've confirmed this logic is correct.)
Specifically, if the page is mounted, and you raise an exception on the page, the exception will cause the error page to be mounted without ever invoking `getInitialProps` on the new App/Error page pairing.
This has been illustrated with multiple repros in #4574.
## Why is it broken
This regression was introduced two months ago in #4156, where the invocation of `getInitialProps` was removed from the app's top-level error handler. Specifically, [this line](https://github.com/zeit/next.js/pull/4156/files#diff-895656aeaccff5d7c0f56a113ede9662L147) was removed and [replaced by a comment](https://github.com/zeit/next.js/pull/4156/files#diff-895656aeaccff5d7c0f56a113ede9662R167) that says that "`App` will handle the calling of `getInitialProps`".
I believe the sentiment about "`App` will handle calling `getInitialProps`" is mistaken. In fact, it really doesn't make sense on its face, since it would require an instance lifecycle method of `App` (which is mounted immediately after the comment) to invoke the `static getInitialProps` method on the error page.
## How I fixed it
I've fixed this in a fork by restoring Lines 146 – 148 that were removed in #4156. I think this is the right fix, but Next.js's handling of `getInitialProps` could certainly be improved. (The code in [this conditional](86d01706a6/client/index.js (L173)) speaks to the unnecessary complexity around this.)
* Handle production errors correctly
* Improved source map support
* Make react-hot-loader hold state again
* Remove console.log
* Load modules on demand
* Catch errors in rewriteErrorTrace
* Update comment
* Update comment
* Remove source-map-support
* Load modules in next-dev
* Make sure error logged has sourcemaps too
* Add tests for production runtime errors
* Add tests for development runtime errors. Fix issue with client side errors in development
* Move functionality back to renderError now that error handling is consistent
* Rename to applySourcemaps
* Add next/config
* Set config on server start / client render
* Add documentation for next/config
* Add next/config support for next export
* Fix test
* Use the correct name
* Set default to empty object on the client side
* Add config tests
* Rename config to runtimeConfig
* Remove special error script handling.
As a result of that, we can't detect 500 errors and buildIdMismatch via client side.
* Fix failing test cases.
* Refactor the code base.
* Remove Router.onAppUpdated
This reverts `fb7c862` per @timneutkens
- Removes the errors/*.md associated
- Puts back `poweredByHeader` for `next.config.js`
- Reincorporates test:
X-Powered-By header
✓ should set it by default (3ms)
✓ should not set it when poweredByHeader==false (5ms)
Also tested with `yarn link` and verified.
* Add example on how to pass data through js api during SSR
Requested in #1117
* Use content negotiation instead of a separate route
* Codereview feedback
* Move security related test cases into a its own file.
* Removes the unused renderScript function
* Add a nerv example. (#3573)
* Add a nerv example.
* Fix for indentation/style
* Fix for name
* Speed up next build
* Document webpack config
* Speed up next build
* Remove comment
* Add comment
* Clean up rules
* Add comments
* Run in parallel
* Push plugins seperately
* Create a new chunk for react
* Don’t uglify react since it’s already uglified. Move react to commons in development
* Use the minified version directly
* Re-add globpattern
* Move loaders into a separate variable
* Add comment linking to Dan’s explanation
* Remove dot
* Add universal webpack
* Initial dev support
* Fix linting
* Add changes from Arunoda's work
* Made next dev works.
But super slow and no HMR support.
* Fix client side hot reload
* Server side hmr
* Only in dev
* Add on-demand-entries client + hot-middleware
* Add .babelrc support
* Speed up on demand entries by running in parallel
* Serve static generated files
* Add missing config in dev
* Add sass support
* Add support for .map
* Add cssloader config and fix .jsx support
* Rename
* use same defaults as css-loader. Fix linting
* Add NoEmitErrorsPlugin
* Add clientBootstrap
* Use webpackhotmiddleware on the multi compiler
* alpha.3
* Use babel 16.2.x
* Fix reloading after error
* Remove comment
* Release 5.0.0-univeral-alpha.1
* Remove check for React 16
* Release 5.0.0-universal-alpha.2
* React hot loader v4
* Use our static file rendering machanism to serve pages.
This should work well since the file path for a page is predictable.
* Release 5.0.0-universal-alpha.3
* Remove optional loaders
* Release 5.0.0-universal-alpha.4
* Remove clientBootstrap
* Remove renderScript
* Make sure pages bundles are served correctly
* Remove unused import
* Revert to using the same code as canary
* Fix hot loader
* Release 5.0.0-universal-alpha.5
* Check if externals dir exist before applying config
* Add typescript support
* Add support for transpiling certain packages in node_modules
Thanks to @giuseppeg’s work in https://github.com/zeit/next.js/pull/3319
* Add BABEL_DISABLE_CACHE support
* Make sourcemaps in production opt-in
* Revert "Add support for transpiling certain packages in node_modules"
This reverts commit d4b1d9babfb4b9ed4f4b12d56d52dee233e862da.
In favor of a better api around this.
* Support typescript through next.config.js
* Remove comments
* Bring back commons.js calculation
* Remove unused dependencies
* Move base.config.js to webpack.js
* Make sure to only invalidate webpackDevMiddleware one after other.
* Allow babel-loder caching by default.
* Add comment about preact support
* Bring back buildir replace
* Remove obsolete plugin
* Remove build replace, speed up build
* Resolve page entries like pages/day/index.js to pages/day.js
* Add componentDidCatch back
* Compile to bundles
* Use config.distDir everywhere
* Make sure the file is an array
* Remove console.log
* Apply optimization to uglifyjs
* Add comment pointing to source
* Create entries the same way in dev and production
* Remove unused and broken pagesGlobPattern
* day/index.js is automatically turned into day.js at build time
* Remove poweredByHeader option
* Load pages with the correct path.
* Release 5.0.0-universal-alpha.6
* Make sure react-dom/server can be overwritten by module-alias
* Only add react-hot-loader babel plugin in dev
* Release 5.0.0-universal-alpha.7
* Revert tests
* Release 5.0.0-universal-alpha.10
* Make sure next/head is working properly.
* Add wepack alias for 'next' back.
* Make sure overriding className in next/head works
* Alias react too
* Add missing r
* Fragment fallback has to wrap the children
* Use min.js
* Remove css.js
* Remove wallaby.js
* Release 5.0.0-universal-alpha.11
* Resolve relative to workdir instead of next
* Make sure we touch the right file
* Resolve next modules
* Remove dotjsx removal plugins since we use webpack on the server
* Revert "Resolve relative to workdir instead of next"
This reverts commit a13f3e4ab565df9e2c9a3dfc8eb4009c0c2e02ed.
* Externalize any locally loaded module lives outside of app dir.
* Remove server aliases
* Check node_modules reliably
* Add symlink to next for tests
* Make sure dynamic imports work locally.
This is why we need it: b545b519b2/lib/MainTemplate.js (L68)
We need to have the finally clause in the above in __webpack_require__.
webpack output option strictModuleExceptionHandling does that.
* dynmaic -> dynamic
* Remove webpack-node-externals
* Make sure dynamic imports support SSR.
* Remove css support in favor of next-css
* Make sure we load path from `/` since it’s included in the path matching
* Catch when ensurepage couldn’t be fulfilled for `.js.map`
* Register require cache flusher for both client and server
* Add comment explaining this is to facilitate hot reloading
* Only load module when needed
* Remove unused modules
* Release 5.0.0-universal-alpha.12
* Only log the `found babel` message once
* Make sure ondemand entries working correctly.
Now we are just using a single instance of OnDemandEntryHandler.
* Better sourcemaps
* Release 5.0.0-universal-alpha.13
* Lock uglify version to 1.1.6
* Release 5.0.0-universal-alpha.14
* Fix a typo.
* Introduce multi-zones support for mircofrontends
* Add section on css
* Dump address.
* Use zero as the port.
* Limit test cases.
* throw address.
* Fail a specific error.
* Set a port manually.
* Make sure jest is working properly.
* Set the jest timeout time to 5 min.
* Run the actual test
* Run all production tests on Travis.
* Set the Jest default timeout to 5 min for all integration tests.
* Remove production only testing.
* Remove unwanted console.log
* Remove the addition number from test case
* Set the static export test jest timeout to 5 min.
* Run tests again if they failed once.
* Layout ground works for next/async
* Implement the Dynamic Bundle feature.
* Add some test cases.
* Update README.
* Implement props aware dynamic bundle API.
* Update tests and README.
* Add a test case for React Context support.
* Always check with the fs when gettings chunks.
* Add a new set of test cases for dynamic imports in dev.
* Add dynamic import test cases for production.
* Add availableChunks support for static exports.
* Introduce script tag based page loading system.
* Call ensurePage only in the dev mode.
* Implement router using the page-loader.
* Fix a typo and remove unwanted code.
* Fix some issues related to rendering.
* Fix production tests.
* Fix ondemand test cases.
* Fix unit tests.
* Get rid of eval completely.
* Remove all the inline code.
* Remove the json-pages plugin.
* Rename NEXT_PAGE_LOADER into __NEXT_PAGE_LOADER__
* Rename NEXT_LOADED_PAGES into __NEXT_LOADED_PAGES__
* Remove some unwanted code.
* Load everything async.
* Remove lib/eval-script.js
We no longer need it.
* Move webpack idle wait code to the page-loader.
Because that's the place to do it.
* Remove pageNotFound key from the error.
* Remove unused error field 'buildError'
* Add much better logic to normalize routes.
* Get rid of mitt.
* Introduce a better way to register pages.
* Came back to the mitt() based page-loader.
* Add link rel=preload support.
* Add assetPrefix support to add support for CDNs.
* Add assetPrefix support for preload links.
* Update readme.md
* Randomize the port returned from test util's findPort().
* Use http's server.listen() to bind to a random available port.
* Update yarn.lock
* Update yarn.lock
* Use jest-cli instead of gulp plugin.
* Use jest-cli instead of gulp plugin.
* Move fixtures into the examples dir.
* Move test code of example app to the basic example.
* Add isolated tests for server/resolve
* Allow tests to use cheerio.
* Use portfinder to get a unique port.
* Move back integration tests into the example dir.
* Introduce next-test-utils.
* Remove gulp-jest
* Add coveralls support.
* Use transpiled version of code in dist.
This is to make sure same file gets covered
by both unit/isolated tests and integration tests.
* Add support for source maps.
* Use code from dist always.
* Use nyc to stop instrument.
* Add integration test suite for production usage.
* Use jest-cli.
* Add support for running e2e tests.
* Check gzipPath with fs.stat before serving
Otherwise, serve package might throw issues other than ENOENT
* Install chromedriver with npm install.
* Install chrome on travis-ci.
* Add --forceExit to Jest.
* Run tests only on Node v6.
That's because selenium-webdriver only supports
Node 6 LTS.
* Use chromedriver NPM module to install chromedriver.
* Use wd as the webdriver client.
* Run chromedriver before tests.
* Run travis for both node 4 and 6
* Remove unwanted npm install script.
* Move some common text utilities to next-test-utils
* Add lint checks and testing in npm prepublish hook.
* Use npm on travis-ci.
We are having some caching issues with yarn and chromedriver.
* Make tests work on windows.\n But chromedriver doesn't work.
* Clean up dependencies.
* Run chromedriver in background without any tools.
* Fix a typo in the code.
* Use ES6 features used in node4 inside the gulpfile.
* Add some comments.
* Add support for running in windows.
* Stop chromedriver properly on windows.
* Fix typos.
