[BUG] NotCapable: Requires env access to "JEST_WORKER_ID"

[eliotik]

The deno-slack versions

"deno-slack-sdk/": "https://deno.land/x/deno_slack_sdk@2.15.1/",
"deno-slack-api/": "https://deno.land/x/deno_slack_api@2.8.0/",

Deno runtime version

deno 2.4.2 (stable, release, aarch64-apple-darwin)
v8 13.7.152.14-rusty
typescript 5.8.3

OS info

ProductName: macOS
ProductVersion: 15.5
BuildVersion: 24F74
Darwin Kernel Version 24.5.0: Tue Apr 22 19:52:00 PDT 2025; root:xnu-11417.121.6~2/RELEASE_ARM64_T6031

Describe the bug

I updated today in the application string value in my custom function and ran slack deploy, everything went well, but while executing workflow in the Slack, we started to have error:

2025-07-18 14:52:56 [info] [Wf096BSKTY8K] (Trace=Tr096JKZH284) Shortcut trigger successfully started execution of function 'Report Bug'
2025-07-18 14:52:56 [info] [Fn096BSKT5J7] (Trace=Tr096JKZH284) Function 'Report Bug' (workflow function) started
2025-07-18 14:52:56 [info] [Wf096BSKTY8K] (Trace=Tr096JKZH284) Workflow 'Report Bug' started
2025-07-18 14:52:56 [info] [Wf096BSKTY8K] (Trace=Tr096JKZH284) Workflow step 1 of 2 started
2025-07-18 14:52:56 [info] [Fn010N] (Trace=Tr096JKZH284) Function 'Collect info in a form' (Slack function) started
2025-07-18 14:52:57 [info] [Wf096BSKTY8K] (Trace=Tr096JKZH284) Workflow step 'Collect info in a form' completed
2025-07-18 14:53:03 [info] [Fn010N] (Trace=Tr096JKZH284) Function 'Collect info in a form' (Slack function) completed
2025-07-18 14:53:03 [info] [Wf096BSKTY8K] (Trace=Tr096JKZH284) Workflow step 'Collect info in a form' completed
2025-07-18 14:53:04 [info] [Wf096BSKTY8K] (Trace=Tr096JKZH284) Workflow step 2 of 2 started
2025-07-18 14:53:04 [info] [Fn096BSKQ61Z] (Trace=Tr096JKZH284) Function 'Report Bug - Validate Initial Input' (app function) started
2025-07-18 14:53:06 [info] [Fn096BSKQ61Z] (Trace=Tr096JKZH284) Function output:
Caught error from user supplied module: NotCapable: Requires env access to "JEST_WORKER_ID", run again with the --allow-env flag
at Object.getEnv [as get] (ext:deno_os/30_os.js:124:10)
at denoEnvGet (ext:deno_node/_process/process.ts:27:21)
at Object.get (ext:deno_node/_process/process.ts:44:22)
at file:///var/task/functions/report-bug-initial-input-validation.js:10932:155

Steps to reproduce

1. slack deploy

❯ slackcli deploy
Check /Users/ap/.slack/logs/slack-debug-20250718.log for error logs

⚠️ App manifest contains some components that may require additional information

📝 This step cannot be used by external teams. Delete the step, or remove the external teams to publish this workflow. (home_team_only)
Source: /workflows/report_bug_workflow/steps/1

📚 App Manifest
Updated app manifest for "Report Bug" in "Stay22"

🏠 App Install
Installing "Report Bug" app to "Stay22"
Updated app icon: assets/icon.png
Finished in 2.7s

⚡ Listing triggers installed to the app...

🔗 Shortcut trigger:

Report Bug Ft087DG3GA9W (shortcut)
Created: 2024-12-28 13:43:33 -05:00 (6 months ago)
Collaborators:
XXXX @xxxx XXXXX
Can be found and used by:
everyone in the workspace
https://slack.com/shortcuts/Ft087DG3GA9W/a99aa0cbaa8e82cbd65cf5a8bbdd5eb0

🎁 App packaged and ready to deploy
0.142MB was packaged in 0.3s

🚀 Report Bug deployed in 1.7s
Dashboard: https://slack.com/apps/A0873CF74P3
App Owner: XXXX (XXXXX)
Workspace: XXXX (XXXXX)

🌩 Visit Slack to try out your live app!
When you make any changes, update your app by re-running slackcli deploy
Review the current activity logs using slackcli activity --tail

💌 We would love to know how things are going
Share your development experience with slackcli feedback

I tried to add this variable JEST_WORKER_ID to slack env but it didn't help.
This is not mine variable and I didn't add any new packages today.

When I run locally slack run I have no error at all.

Expected result

Workflow should work fine as it was before.

Actual result

2025-07-18 14:53:06 [info] [Fn096BSKQ61Z] (Trace=Tr096JKZH284) Function output:
Caught error from user supplied module: NotCapable: Requires env access to "JEST_WORKER_ID", run again with the --allow-env flag
at Object.getEnv [as get] (ext:deno_os/30_os.js:124:10)
at denoEnvGet (ext:deno_node/_process/process.ts:27:21)
at Object.get (ext:deno_node/_process/process.ts:44:22)
at file:///var/task/functions/report-bug-initial-input-validation.js:10932:155

Requirements

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[zimeg]

Hey @eliotik 👋 Thanks for writing in!

The most recent redeployment might've brought an unexpected change behind the scenes to how environment variables can be accessed, which might be causing this problem - we're now targeting Deno 2 with the deploy command.

AFAICT that shouldn't have changed application behavior though. This guide has an example of how this might be done from within a function:

export default SlackFunction(MyFunctionDefinition, ({ env }) => {
  const myEnvVar = env["MY_ENV_VAR"];
  // ...
});

Is it possible to share the portion of code throwing this error? I'm wanting to make sure it's not using the methods shown for the Deno runtime itself 🔍

[eliotik]

Thank you @zimeg for the prompt response and suggestions, afaik it is not part of my code. It may be coming from some package but I was not able to identify which package needs it. Plus JEST_WORKER_ID is an env var for Jest, so I'm perplexed which packages from my code started to use it.
But again, I didn't add new packages or updated versions of existing packages.

[zimeg]

@eliotik Of course! And this is interesting to me...

I'm not aware either of which package might be causing this based on the error, but if logging within the function narrows this down or if example code is available please keep us updated!

We'll keep watch for similar errors in the meantime 👁️‍🗨️

[eliotik]

The problem is that I don't get any logs from my function, error appears before entering my code.

As you can see in activities output:

Is there anyway I could download compiled file to review code:
file:///var/task/functions/report-bug-initial-input-validation.js:10932:155
So at least I can take a look what is at line 10932

[eliotik]

I enabled debug mode,
slackcli env add SLACK_DEBUG true

hoping to get more output, but it didn't help, it was the same output.

[eliotik]

Hey @zimeg , something happened about couple days ago because it fixed itself on your side without me redeploying or changing code. I wonder if it is possible to track back what was changed.