Cannot Deploy; EMFILE: too many open files

[GrantPerkins]

Are you certain it's a bug?

• Yes, it looks like a bug

Is the issue caused by a plugin?

• It is not a plugin issue

Are you using the latest version?

• Yes, I'm using the latest version

Is there an existing issue for this?

• I have searched existing issues, it hasn't been reported yet

Issue description

When running serverless deploy through CLI, I get some variation of the below error.

 Serverless Error ----------------------------------------

  Cannot read file node_modules\rxjs\operator\groupBy.d.ts due to: EMFILE: too many open files, open 'C:\Users\gcper\Code\190\Website\lambda\node_modules\rxjs\operator\groupBy.d.ts'

I cannot deploy to my lambda functions.

Service configuration (serverless.yml) content

service: team190

frameworkVersion: '2'

provider:
  name: aws
  runtime: python3.8
  iamRoleStatements:
    - Effect: "Allow"
      Action:
        - dynamodb:Query
        - dynamodb:Scan
        - dynamodb:GetItem
        - dynamodb:PutItem
        - dynamodb:UpdateItem
        - dynamodb:DeleteItem
      Resource: "*"
plugins:
  - serverless-python-requirements


custom:
  pythonRequirements:
    dockerizePip: non-linux

functions:
  login:
    handler: handler/handler.login
  choose:
    handler: handler/handler.assign_role
  request:
    handler: handler/student_handler.request
  get_requests:
    handler: handler/uber_handler.get_requests
  get_records:
    handler: handler/handler.get_records
  confirm_requests:
    handler: handler/uber_handler.confirm_requests
  create_poll:
    handler: handler/uber_handler.create_poll
  get_users:
    handler: handler/uber_handler.get_all_users
  create_event:
    handler: handler/uber_handler.create_event
  get_pending_requests:
    handler: handler/student_handler.get_pending_requests
  delete_pending_requests:
    handler: handler/student_handler.delete_pending_requests

Command name and used flags

serverless deploy

Command output

Serverless: Running "serverless" installed locally (in service node_modules)
Serverless: Deprecation warning: Resolution of lambda version hashes was improved with better algorithm, which will be used in next major release.
            Switch to it now by setting "provider.lambdaHashingVersion" to "20201221"
            More Info: https://www.serverless.com/framework/docs/deprecations/#LAMBDA_HASHING_VERSION_V2
Serverless: Generated requirements from C:\Users\gcper\Code\190\Website\lambda\requirements.txt in C:\Users\gcper\Code\190\Website\lambda\.serverless\requirements.txt...
Serverless: Using static cache of requirements found at C:\Users\gcper\AppData\Local\UnitedIncome\serverless-python-requirements\Cache\b729430ab9c5421667932cf132fc2b7c75df8e7e25338978deedaf75b5fec293_slspyc ...
Serverless: Packaging service...
Serverless: Excluding development dependencies...

 Serverless Error ----------------------------------------

  Cannot read file node_modules\rxjs\operator\groupBy.d.ts due to: EMFILE: too many open files, open 'C:\Users\gcper\Code\190\Website\lambda\node_modules\rxjs\operator\groupBy.d.ts'

  Get Support --------------------------------------------
     Docs:          docs.serverless.com
     Bugs:          github.com/serverless/serverless/issues
     Issues:        forum.serverless.com

  Your Environment Information ---------------------------
     Operating System:          win32
     Node Version:              14.16.1
     Framework Version:         2.64.1 (local)
     Plugin Version:            5.5.0
     SDK Version:               4.3.0
     Components Version:        3.17.1

Environment information

Serverless: Running "serverless" installed locally (in service node_modules)
Framework Core: 2.64.1 (local)
Plugin: 5.5.0
SDK: 4.3.0
Components: 3.17.1

[medikoo]

@GrantPerkins great thanks for reporting. Can you post the output but when command is run with SLS_DEBUG=* flag?

[DominikIlski]

Hi i have the same problem and to my knowledge it is not dependend on config files. This error is really hard to reproduce, and the higher chance to do so is when node_module is filled with packages. My coleagues running the same command on the same repo does not have this problem. But unfortunetly it does exists and its stops me from developing :(
For eg. part of my package.json file:

"devDependencies": {
    "@babel/core": "^7.15.5",
    "@babel/preset-env": "^7.15.6",
    "@babel/register": "^7.15.3",
    "prettier": "^2.4.1",
    "serverless-lift": "^1.9.0"
  },
  "dependencies": {
    "@sentry/serverless": "^6.13.3",
    "aws-sdk": "^2.997.0",
    "node-fetch": "^2.6.5",
    "node-fetch-retry": "^2.0.0",
    "yup": "^0.32.11"
  }

This is my output after running sls deploy -s prod:

Serverless: To ensure safe major version upgrades ensure "frameworkVersion" setting in service configuration (recommended setup: "frameworkVersion: ^2.64.1")

Serverless: Load command interactiveCli
Serverless: Load command config
Serverless: Load command config:credentials
Serverless: Load command config:tabcompletion
Serverless: Load command config:tabcompletion:install
Serverless: Load command config:tabcompletion:uninstall
Serverless: Load command create
Serverless: Load command install
Serverless: Load command package
Serverless: Load command deploy
Serverless: Load command deploy:function
Serverless: Load command deploy:list
Serverless: Load command deploy:list:functions
Serverless: Load command invoke
Serverless: Load command invoke:local
Serverless: Load command info
Serverless: Load command logs
Serverless: Load command metrics
Serverless: Load command print
Serverless: Load command remove
Serverless: Load command rollback
Serverless: Load command rollback:function
Serverless: Load command slstats
Serverless: Load command plugin
Serverless: Load command plugin
Serverless: Load command plugin:install
Serverless: Load command plugin
Serverless: Load command plugin:uninstall
Serverless: Load command plugin
Serverless: Load command plugin:list
Serverless: Load command plugin
Serverless: Load command plugin:search
Serverless: Load command config
Serverless: Load command config:credentials
Serverless: Load command upgrade
Serverless: Load command uninstall
Serverless: Load command lift
Serverless: Load command lift:eject
Serverless: Load command HooksQueue:logs
Serverless: Load command HooksQueue:send
Serverless: Load command HooksQueue:failed
Serverless: Load command HooksQueue:failed:purge
Serverless: Load command HooksQueue:failed:retry
Serverless: Load command login
Serverless: Load command logout
Serverless: Load command generate-event
Serverless: Load command test
Serverless: Load command dashboard
Serverless: Load command output
Serverless: Load command output:get
Serverless: Load command output:list
Serverless: Load command param
Serverless: Load command param:get
Serverless: Load command param:list
Serverless: Load command studio
Serverless: Skipping variables resolution with old resolver (new resolver reported no more variables to resolve)
Serverless: Configuration warning at 'constructs.HooksQueue': unsupported configuration format
Serverless:  
Serverless: Learn more about configuration validation here: http://slss.io/configuration-validation
Serverless:  
Serverless: Invoke deploy
Serverless: Invoke package
Serverless: Invoke aws:common:validate
Serverless: Invoke aws:common:cleanupTempDir
Serverless: Packaging service...
Serverless: Excluding development dependencies...
Serverless: Excluding development dependencies...
Serverless: Excluding development dependencies...

 Serverless Error ----------------------------------------

  ServerlessError: Cannot read file node_modules\@types\lodash\fp\thru.d.ts due to: EMFILE: too many open files, open 'C:\PRACA_STUDIA\PRACACODEWAVE\webhooks-execution\node_modules\@types\lodash\fp\thru.d.ts'
      at C:\Users\DominioPianino\AppData\Roaming\nvm\v15.0.1\node_modules\serverless\lib\plugins\package\lib\zipService.js:126:15
      at tryCatcher (C:\Users\DominioPianino\AppData\Roaming\nvm\v15.0.1\node_modules\serverless\node_modules\bluebird\js\release\util.js:16:23)
      at Promise._settlePromiseFromHandler (C:\Users\DominioPianino\AppData\Roaming\nvm\v15.0.1\node_modules\serverless\node_modules\bluebird\js\release\promise.js:547:31)
      at Promise._settlePromise (C:\Users\DominioPianino\AppData\Roaming\nvm\v15.0.1\node_modules\serverless\node_modules\bluebird\js\release\promise.js:604:18)
      at Promise._settlePromise0 (C:\Users\DominioPianino\AppData\Roaming\nvm\v15.0.1\node_modules\serverless\node_modules\bluebird\js\release\promise.js:649:10)
      at Promise._settlePromises (C:\Users\DominioPianino\AppData\Roaming\nvm\v15.0.1\node_modules\serverless\node_modules\bluebird\js\release\promise.js:725:18)
      at _drainQueueStep (C:\Users\DominioPianino\AppData\Roaming\nvm\v15.0.1\node_modules\serverless\node_modules\bluebird\js\release\async.js:93:12)
      at _drainQueue (C:\Users\DominioPianino\AppData\Roaming\nvm\v15.0.1\node_modules\serverless\node_modules\bluebird\js\release\async.js:86:9)
      at Async._drainQueues (C:\Users\DominioPianino\AppData\Roaming\nvm\v15.0.1\node_modules\serverless\node_modules\bluebird\js\release\async.js:102:5)
      at Immediate.Async.drainQueues [as _onImmediate] (C:\Users\DominioPianino\AppData\Roaming\nvm\v15.0.1\node_modules\serverless\node_modules\bluebird\js\release\async.js:15:14)
      at processImmediate (node:internal/timers:462:21)

  Get Support --------------------------------------------
     Docs:          docs.serverless.com
     Bugs:          github.com/serverless/serverless/issues
     Issues:        forum.serverless.com

  Your Environment Information ---------------------------
     Operating System:          win32
     Node Version:              15.0.1
     Framework Version:         2.64.1
     Plugin Version:            5.5.0
     SDK Version:               4.3.0
     Components Version:        3.17.1

and when there are some fixes for a linux based environment, but it is hard to achieve on a windows.
According to:
https://stackoverflow.com/questions/8965606/node-and-error-emfile-too-many-open-files

Note: File that is shown in a error output is not always the same one.

[medikoo]

@DominikIlski we have EMFILE prevention baked in. Still it cannot handle eventual sync fs calls which we practice only when reading user configuration.

Other corner case scenario, where eventually EMFILE may sneak unhadled, is if any shared dependency between serverless and .e.g @servleress/components requires fs and attaches to it's functions in module initialization.

If there is such scenario anywhere, then this will be fixed with next release (as with serverless/serverless#10131 we've ensured to not require other CLI's modules if they're not run)

[migcoldev]

I could deploy on my PC but not on the laptop. The next day, without making any updates, no changes, I can no longer deploy both. I get the same "EMFILE: too many open files" error

Today updated nodejs, serverless, and still with issue.

[FrodoBaggyMcBaggins]

FWIW - I was/am experiencing this with Python. I created a virtual environment for each Lambda handler - and it looks like serverless is including all of the /Lib and /Scripts directories for each virtual environment, thereby inflating the file count needed to package.

Adding exclusions "solved" this for me.

[jvanalst]

I just also ran into this while working on Windows 10 randomly.
Nothing changed on my system or project except for an npm audit fix that upgraded a single package.

I tried reinstalling my packages from scratch but had no joy.

Framework Core: 2.71.0 (local)
Plugin: 5.5.3
SDK: 4.3.0
Components: 3.18.1

[jvanalst]

I ended up using serverless-plugin-include-dependencies@v4.1.0 and it solved the problem. It also dramatically decreased build time. I'm not a fan of having the extra dependency though, but it does seem to be a viable work around.

[medikoo]

I've moved this issue to https://github.com/serverless/serverless-python-requirements repository, as it seems specific to this plugin

[FrodoBaggyMcBaggins]

@medikoo I don't believe that's the case - this issue can be encountered without having serverless-python-requirements installed. It seems more closely related to the combination of serverless with a virtual environment in the directory being packaged.

[medikoo]

@FrodoBaggyMcBaggins can you create a sample reproduction case, that doesn't involve any plugins, and provide a link?

[jvanalst]

@medikoo - I can guarantee it's not specific to the serverless-python-requirements plugin (I'm not using that one at all). I can't rule out other plugins having similar issues though, as I'm using:

plugins:
  - serverless-s3-sync
  - serverless-offline
  - serverless-export-env

[medikoo]

@jvanalst are you capable to prepare a reproduction test case that doesn't involve any plugins? Or if not, can you single out which plugin causes that?