gatsby develop -> Cannot read property 'indexOf' of undefined

[tleunen]

I reinstalled gatsby, I guess one of the dependencies was updated and now I get this error when I run gatsby develop

Debug: internal, implementation, error 
    TypeError: Uncaught error: Cannot read property 'indexOf' of undefined
  at getFilenameFromUrl (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/webpack-dev-middleware/middleware.js:129:9)
  at webpackDevMiddleware (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/webpack-dev-middleware/middleware.js:174:18)
  at /Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi-webpack-plugin/lib/index.js:58:5
  at /Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/lib/handler.js:311:22
  at iterate (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/node_modules/items/lib/index.js:35:13)
  at done (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/node_modules/items/lib/index.js:27:25)
  at Function.wrapped [as _next] (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/node_modules/hoek/lib/index.js:858:20)
  at Function.internals.continue (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/lib/reply.js:105:10)
  at /Users/tleunen/dev/tp/node_modules/gatsby/dist/utils/develop.js:146:25
  at /Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/lib/handler.js:311:22
  at iterate (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/node_modules/items/lib/index.js:35:13)
  at Object.exports.serial (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/node_modules/items/lib/index.js:38:9)
  at /Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/lib/handler.js:306:15
  at [object Object].internals.Protect.run (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/lib/protect.js:56:5)
  at Object.exports.invoke (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/lib/handler.js:304:22)
  at [object Object].internals.Request._execute (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/lib/request.js:311:13)
  at Domain.<anonymous> (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/lib/connection.js:246:25)
  at Domain.run (domain.js:228:14)
  at Server.<anonymous> (/Users/tleunen/dev/tp/node_modules/gatsby/node_modules/hapi/lib/connection.js:244:37)
  at emitTwo (events.js:100:13)
  at Server.emit (events.js:185:7)
  at HTTPParser.parserOnIncoming [as onIncoming] (_http_server.js:537:12)
  at HTTPParser.parserOnHeadersComplete (_http_common.js:103:23)

After investigation, inside the develop script, this is true negotiator.mediaType() === 'text/html'. Therefore, the system tries to load a page at /html/ but nothing exists there...

[tleunen]

So after investigation, it's indeed a dependency. And it's webpack-dev-middleware. The version 1.5.1 works, but v1.6.0 doesn't work with gatsby.

[KyleAMathews]

webpack/webpack-dev-middleware@b05cd04 is what broke things.

There's an open PR to fix it webpack/webpack-dev-middleware#80

[KyleAMathews]

Note, this isn't a direct dependency of Gatsby. We depend on https://github.com/SimonDegraeve/hapi-webpack-plugin which depends on webpack-dev-middleware.

[KyleAMathews]

1.6.1 of webpack-dev-middleware was released today which rolled-back the regression. webpack/webpack-dev-middleware@8044d04