frequent server crashes with "Cannot read propert 'children' of undefined"

[jeffwillette]

Description

Describe the issue or the enhancement that you want to see.

Steps to reproduce

I don't have a large enough scope of the problem to get repro steps yet, will add them when and if I do.

Clear steps describing how to reproduce the issue.

Expected result

No dev server crash

What should happen?

Actual result

server crashed with trace

info file deleted at /Users/Jeff/go/src/github.com/deltaskelta/interviews/frontend/src/pages/app/index.js
error UNHANDLED EXCEPTION


  TypeError: Cannot read property 'children' of undefined

  - actions.js:379 actions.deleteNode
    [frontend]/[gatsby]/dist/redux/actions.js:379:54

  - bindActionCreators.js:7 Object.deleteNode
    [frontend]/[redux]/lib/bindActionCreators.js:7:35

  - gatsby-node.js:163
    [frontend]/[gatsby]/dist/internal-plugins/internal-data-bridge/gatsby-node.js:163:23

  - mitt.js:1
    [frontend]/[mitt]/dist/mitt.js:1:268

  - Array.map

  - mitt.js:1 Object.emit
    [frontend]/[mitt]/dist/mitt.js:1:252

  - index.js:72
    [frontend]/[gatsby]/dist/redux/index.js:72:11

  - createStore.js:186 dispatch
    [frontend]/[redux]/lib/createStore.js:186:7

  - index.js:58
    [frontend]/[gatsby]/dist/redux/index.js:58:79

  - bindActionCreators.js:7
    [frontend]/[redux]/lib/bindActionCreators.js:7:12

  - api-runner-node.js:47 doubleBoundActionCreators.(anonymous function)
    [frontend]/[gatsby]/dist/utils/api-runner-node.js:47:13

  - gatsby-node.js:69
    [frontend]/[gatsby]/dist/internal-plugins/component-page-creator/gatsby-node.js:69:17

  - Array.forEach

  - gatsby-node.js:68 FSWatcher.<anonymous>
    [frontend]/[gatsby]/dist/internal-plugins/component-page-creator/gatsby-node.js:68:18

  - index.js:196 FSWatcher.<anonymous>
    [frontend]/[chokidar]/index.js:196:15


error An unexpected error occurred: "Command failed.
Exit code: 1
Command: sh
Arguments: -c gatsby develop
Directory: /Users/Jeff/go/src/github.com/deltaskelta/interviews/frontend
Output:
".
info If you think this is a bug, please open a bug report with the information provided in "/Users/Jeff/go/src/github.com/deltaskelta/interviews/frontend/yarn-error.log".
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

What happened.

Environment

I am in the middle of trying to integrate an external Apollo store when this happens, It happens when I am editing and saving graphql queries that are external to gatsby's static build queries

• Gatsby version (npm list gatsby): gatsby@1.9.231
• gatsby-cli version (gatsby --version): 1.1.41
• Node.js version: v9.8.0
• Operating System: OSSierra 10.13.3

File contents (if changed):

gatsby-config.js:
package.json:
gatsby-node.js:
gatsby-browser.js:

import { ApolloLink } from 'apollo-link';
import { ApolloProvider } from 'react-apollo';
import { HttpLink, InMemoryCache } from 'apollo-client-preset';
import { Provider } from 'react-redux';
import { withClientState } from 'apollo-link-state';
import PropTypes from 'prop-types';

import { ApolloClient } from 'apollo-client';
import { Router } from 'react-router-dom';
import React from 'react';

import { getCookie } from './utils';
import apolloState from './src/state/defaults';
import newStore from './src/state/createStore';
import resolvers from './src/state/resolvers';
import urls from './urls';

// this is for the usage of redux
exports.replaceRouterComponent = ({ history }) => {
  const ConnectedRouterWrapper = ({ children }) => {
    const store = newStore();
    return (
      <Provider store={store}>
        <Router history={history}>{children}</Router>
      </Provider>
    );
  };

  ConnectedRouterWrapper.propTypes = {
    children: PropTypes.object
  };

  return ConnectedRouterWrapper;
};

exports.wrapRootComponent = ({ Root }) => {
  return () => {
    const cache = new InMemoryCache();

    const stateLink = withClientState({ resolvers, cache, apolloState });

    const httpLink = new HttpLink({
      uri: urls.graphqlServer + urls.graphqlEndpoint,
      credentials: 'same-origin',
      headers: {
        authorization: getCookie('Authorization')
      }
    });

    const client = new ApolloClient({
      cache,
      link: new ApolloLink.from([stateLink, httpLink]),
      connectToDevTools: true
    });

    window.__APOLLO_CLIENT__ = client;

    return (
      <ApolloProvider client={client}>
        <Root />
      </ApolloProvider>
    );
  };
};

gatsby-ssr.js:

[jeffwillette]

I am going to close this for now as I had a rather large mistake in the constructor for Apollo Link that seemed to fix the problem when it was removed. (it should not be called with new ApolloLink).

I have not seen the error since I fixed that

[jeffwillette]

oops, I may have closed this a bit too soon, the error is still there...

[m-allanson]

@deltaskelta If you can push up a repo that reproduces this problem then someone should be able to take a closer look.

[jeffwillette]

@m-allanson I am trying but I have been unsuccessful so far. I have a feeling this is related to my vim plugins deleting and replacing files since I experienced the same thing in another issue.

@KyleAMathews is it immediately obvious that this might be related to what I was experiencing in #4162 ?

[KyleAMathews]

Yeah, looks similar. This should be a pretty easy PR @deltaskelta if you'd like to try solving it. Add a check that the thing still exists in

gatsby/packages/gatsby/src/redux/actions.js

Line 414 in b1a470d

actions.deleteNode = (nodeId: string, node: any, plugin: Plugin) => {

Since you're the only one who's seeing it as far we know, you're ideally suited to fix it :-D

This is the instructions for how to set up an environment for testing changes against core https://www.gatsbyjs.org/docs/how-to-contribute/

[jeffwillette]

ok ill give it a shot when I have a free second to follow all the dev environment instructions