"Error: Cannot find module" or "TypeError: Cannot read property 'minify' of undefined" - temporary issues from webpack and terser

[0xi4o]

When I run yarn start:lambda I get the following error:

yarn run v1.12.3
$ netlify-lambda serve src
netlify-lambda: Starting server
Lambda server is listening on 9000
module.js:549
    throw err;
    ^

Error: Cannot find module '/home/ilangorajagopal/Projects/dotconfig/functions/lambda/generate'
    at Function.Module._resolveFilename (module.js:547:15)
    at Function.resolve (internal/module.js:18:19)
    at Object.clearCache (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/netlify-lambda/lib/serve.js:130:36)
    at /home/ilangorajagopal/Projects/dotconfig/functions/node_modules/netlify-lambda/bin/cmd.js:38:16
    at Array.forEach (<anonymous>)
    at Watching.handler (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/netlify-lambda/bin/cmd.js:37:32)
    at compiler.hooks.done.callAsync (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/webpack/lib/Watching.js:98:9)
    at AsyncSeriesHook.eval [as callAsync] (eval at create (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:6:1)
    at AsyncSeriesHook.lazyCompileHook (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/tapable/lib/Hook.js:154:20)
    at Watching._done (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/webpack/lib/Watching.js:97:28)
    at onCompiled (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/webpack/lib/Watching.js:47:18)
    at hooks.afterCompile.callAsync.err (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/webpack/lib/Compiler.js:630:14)
    at AsyncSeriesHook.eval [as callAsync] (eval at create (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:6:1)
    at AsyncSeriesHook.lazyCompileHook (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/tapable/lib/Hook.js:154:20)
    at compilation.seal.err (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/webpack/lib/Compiler.js:627:30)
    at AsyncSeriesHook.eval [as callAsync] (eval at create (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:6:1)
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

Seeing a previous similar issue, I tried to build it first to see if that would run serve properly. But I get this error when I run yarn build:lambda:

yarn run v1.12.3
yarn run v1.12.3
$ netlify-lambda build src
netlify-lambda: Building functions
Hash: 7158f52f423c80f8443f
Version: webpack 4.29.0
Time: 400ms
Built at: 2019-02-03 09:50:24
      Asset      Size  Chunks  Chunk Names
generate.js  3.76 KiB       0  generate
Entrypoint generate = generate.js
[0] ./generate.js 128 bytes {0} [built]

ERROR in generate.js from Terser
TypeError: Cannot read property 'minify' of undefined
    at minify (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/terser-webpack-plugin/dist/minify.js:175:23)
    at module.exports (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/terser-webpack-plugin/dist/worker.js:13:40)
    at handle (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/worker-farm/lib/child/index.js:44:8)
    at process.<anonymous> (/home/ilangorajagopal/Projects/dotconfig/functions/node_modules/worker-farm/lib/child/index.js:51:3)
    at emitTwo (events.js:126:13)
    at process.emit (events.js:214:7)
    at emit (internal/child_process.js:772:12)
    at _combinedTickCallback (internal/process/next_tick.js:141:11)
    at process._tickCallback (internal/process/next_tick.js:180:9)
Done in 2.02s.

Here is my package.json:

{
  "name": "functions",
  "version": "0.1.0",
  "description": "",
  "private": true,
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start:lambda": "netlify-lambda serve src",
    "build:lambda": "netlify-lambda build src"
  },
  "keywords": [],
  "author": "Ilango Rajagopal",
  "license": "ISC",
  "devDependencies": {
    "netlify-lambda": "^1.3.1"
  }
}

netlify.toml:

[build]
  command = "yarn build:lambda"
  functions = "lambda" #  netlify-lambda reads this

src/generate.js

exports.handler = function(event, context, callback) {
	// your server-side functionality
	console.log('Hello, Netlify!');
};

I'm running Node 8.10.0. When I was first testing Netlify functions last week with a similar set of files, it worked perfectly. Unfortunately I no longer have that code.

[danew]

I had a similar issue with the build step.

As a temporary fix disabling the minimizing of the functions works. Here's how to do that Webpack Configuration.

It seems that other people are also having similar issues with the serve script too, see Issue #111

[swyxio]

hmm. making a small sample repo to try to reproduce. thanks for filing

EDIT: I can reproduce, and this is broken since v1.0.0 (v0.4.0 works). investigating

[swyxio]

based on how recent all these reports are coming up, this seems to be a bug in the terser API: vuejs/vue-cli#3407 (comment)

[swyxio]

confirmed. pls wait for them to resolve, or pin the resolution of terser for now: terser/terser#251

[0xi4o]

Thank you for replying so soon! My side project was held up because I couldn't find a solution to this.

The terser update was pushed only a few hours ago. Building with [email protected] works. And I can now confirm that serve works with [email protected].

[swyxio]

yes because it uses an older webpack version. anyway, i think i'm gonna close this as its a upstream issue that should be fixed soon (angular, vue, react are all affected lol so we have company). cheers

[swyxio]

i think this has been resolved, ping me if not

[0xi4o]

@sw-yx Yes! Both serve and build works with latest version. Thanks.