TypeError: Cannot read property 'edges' of undefined

[isaiahnixon]

I am using a Windows 10 machine. Using an administrator Git Bash terminal I cloned the repo. Then using the Windows "Node.js Command Prompt" I ran the npm install and start commands. The Installation went fine, but when the application launched on port 3000 in Google Chrome I immediately received this error:

TypeError: Cannot read property 'edges' of undefined
displayCategories
C:/Users/windows_user/node.js/bulletin-react/src/components/Layout/drawer.js:26
  23 |     <ListItemText secondary={`All`} />
  24 |   </ListItem>
  25 | </Link>
> 26 | {data.categories.edges.map(category => (
  27 |   <Link
  28 |     key={category.node.id}
  29 |     to={`/category/${category.node.slug}`}
View compiled
SideComponent.render
C:/Users/windows_user/node.js/bulletin-react/src/components/Layout/drawer.js:80
  77 | </Link>
  78 | <Divider />
  79 | <ListSubheader>Categories</ListSubheader>
> 80 | {displayCategories(this.props)}
  81 | <Divider />
  82 | <ListItem button>
  83 |   <ListItemIcon>
View compiled
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[pantharshit00]

just add a short circuit check.

{data.categories && .....}

i have implemented that in my latest pr.

The error rose as you internet might be not so good.or apiserver is not started. make sure to use node 8.

[SebastianCApostolescu]

Weird. I can't replicate the issue.

[pantharshit00]

@SebastianCApostolescu You internet would be fine. We just need to add a check for the data

[isaiahnixon]

@pantharshit00 That solved it, thanks! I also had to add a check to line 8 of ListView.js since it references edges as well.