Jupyter crashes with pyodide error 'NameError: name 'false' is not defined' when trying to use lite mode

[sok82]

Description

When I'm trying to use Jupyter component liteMode=true and pass python code for execution to Output component I got an error of pyodide with error message

Traceback (most recent call last):
  File "/lib/python311.zip/_pyodide/_base.py", line 573, in eval_code_async
    await CodeRunner(
  File "/lib/python311.zip/_pyodide/_base.py", line 395, in run_async
    await coroutine
  File "<exec>", line 6, in <module>
NameError: name 'false' is not defined

Reproduce

Simplified version of my code

function MyComponent({code, kernel} : {code:string, kernel}) {
const [executeTrigger, setExecuteTrigger] = useState(0);

return <Jupyter 
                  lite={true}
                  useRunningKernelIndex={-1}
                  startDefaultKernel={true}
                  terminals={false}             
              >
                 <Output                    
                        sourceId="src-1"
                        codePre=""
                        autoRun={false}
                        kernel={kernel}
                        code={code}
                        showEditor={false}
                        showControl={false}
                        executeTrigger={executeTrigger}      
              />

</Jupyter>
}

Steps to reproduce

1. Initialization works fine
2. I execute code by incrementing executeTrigger
3. When I set code value to something like

job_satisfaction_rate_train = pd.read_csv('https://my.domain.com/datasets/dataset.csv')

execution also doesn't return any error

4. But when I set code value

plt.hist(job_satisfaction_rate_train['job_satisfaction_rate'], bins=50);
plt.grid();

I got pyodide error NameError: name 'false' is not defined

• Everything works fine when lite mode is false and remote server is used
• plt package is imported earlier

Browser logs data

Existing JupyterLite ServiceWorkers unregistered
service-manager.ts:60 Registering new JupyterLite ServiceWorker http://localhost:3000/[object Object]
State.ts:167 Kernel Manager is Ready KernelManager
State.ts:202 Starting Kernel Name: python

then

script has an unsupported MIME type ('text/html').
pyodide.asm.js:9 Loading micropip, packaging
pyodide.asm.js:9 Loading micropip, packaging
pyodide.asm.js:9 Loaded micropip, packaging
pyodide.asm.js:9 Loaded micropip, packaging
kernel.js:40 Uncaught (in promise) PythonError: Traceback (most recent call last):
  File "/lib/python311.zip/_pyodide/_base.py", line 573, in eval_code_async
    await CodeRunner(
  File "/lib/python311.zip/_pyodide/_base.py", line 395, in run_async
    await coroutine
  File "<exec>", line 6, in <module>
NameError: name 'false' is not defined

[echarles]

I have tried this recently and was not able to reproduce. @sok82 Are you still facing the issue?

[sok82]

Hey @echarles ,
returned back to this issue

It's still here and I guess the problem is in URL that is used to load serviceWorker.
In debug mode I see that workerUrl that is used to load is http://localhost:3000/[object%20Object]?enableCache=false

And in response to this URL serviceWorker could not be loaded here in service-manager.js here

 if (!registration && serviceWorker) {
            try {
                // eslint-disable-next-line no-console
                console.info('Registering new JupyterLite ServiceWorker', workerUrl);
                registration = await serviceWorker.register(workerUrl);
                // eslint-disable-next-line no-console
                console.info('JupyterLite ServiceWorker was sucessfully registered');
            } catch (err) {
                console.warn(err);
                console.warn(`JupyterLite ServiceWorker registration unexpectedly failed: ${err}`);
            }
        }

[doelgonzo]

Hey @echarles , returned back to this issue

It's still here and I guess the problem is in URL that is used to load serviceWorker. In debug mode I see that workerUrl that is used to load is http://localhost:3000/[object%20Object]?enableCache=false

And in response to this URL serviceWorker could not be loaded here in service-manager.js here

 if (!registration && serviceWorker) {
            try {
                // eslint-disable-next-line no-console
                console.info('Registering new JupyterLite ServiceWorker', workerUrl);
                registration = await serviceWorker.register(workerUrl);
                // eslint-disable-next-line no-console
                console.info('JupyterLite ServiceWorker was sucessfully registered');
            } catch (err) {
                console.warn(err);
                console.warn(`JupyterLite ServiceWorker registration unexpectedly failed: ${err}`);
            }
        }

I was getting this workerUrl until i started packaging this with yarn, not sure that is your issue, but I was consistently seeing the above until I made the switch from npm to yarn. Not sure why it matters, but it matters.

[echarles]

Great. I let you close as resolved.