Shiny images 404 on Posit Connect Cloud

[jimjam-slam]

I have:

• searched the issue tracker for similar issues
• installed the latest version of Quarto CLI
  • Mine's about 4 months old, but the bug concerns the PPC version of Quarto, not my local one
• formatted my issue following the Bug Reports guide

Bug description

I'm helping a colleague with a Quarto Dashboard that uses Shiny for Python. It runs well locally, but when I deploy the app to Posit Connect Cloud, I'm not able to get external images (in this case, pre-computed figures) to load at all. I've tried putting them in both images and www, and I've tried adding the paths under resources, resource-path, format.dashboard.resources and format.dashboard.resource-path. No combination of this seems to get images loading, either with a client-side path of /images, /www or /www/images.

I have a reprex here:

• Code: https://github.com/jimjam-slam/test-ppc-quarto-shiny-python
• Deployment: https://019f36e5-6cd4-8499-c5b0-da30f2923e6a.share.connect.posit.cloud/

Local view (the image in this test case is an orange square):

Deployed view:

Note that I'm deploying this by connecting the repo on PPC, not using quarto publish. So Shiny itself does work in the actual example, it's just the images that are giving me some trouble 🤔

Your environment

Posit Connect Cloud

Quarto check output

Quarto 99.9.9
[✓] Checking environment information...
      Quarto cache location: /Users/jimjamslam/Library/Caches/quarto
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.8.3: OK
      Dart Sass version 1.87.0: OK
      Deno version 2.4.5: OK
      Typst version 0.14.2: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 99.9.9
      commit: 5b88d3dfe1519179e2e8753c44e058a11ab62ff3
      Path: /Users/jimjamslam/code/tools/quarto-cli/package/dist/bin

[✓] Checking tools....................OK
      TinyTeX: (not installed)
      Chromium: (not installed)
      Chrome Headless Shell: (not installed)
      VeraPDF: (not installed)

[✓] Checking LaTeX....................OK
      Tex:  (not detected)

[✓] Checking Chrome Headless....................OK
      Using: Chrome found on system
      Path: /Applications/Google Chrome.app/Contents/MacOS/Google Chrome
      Source: MacOS known location

[✓] Checking basic markdown render....OK

[✓] Checking R installation...........OK
      Version: 4.5.2
      Path: /Library/Frameworks/R.framework/Versions/4.5-arm64/Resources
      LibPaths:
        - /Users/jimjamslam/Library/R/arm64/4.5/library
        - /Library/Frameworks/R.framework/Versions/4.5-arm64/Resources/library
      knitr: 1.51
      rmarkdown: 2.31

[✓] Checking Knitr engine render......OK

[✓] Checking Python 3 installation....OK
      Version: 3.13.13
      Path: /Users/jimjamslam/Code/tests/test-ppc-quarto-shiny-python/.venv/bin/python3
      Jupyter: 5.9.1
      Kernels: python3

(\) Checking Jupyter engine render....[IPKernelApp] WARNING | Kernel is running over TCP without encryption. All communication (including code and outputs) is sent in plain text and is susceptible to eavesdropping. Use IPC transport or launch with kernel manager-provisioned CurveZMQ keys to enable transport encryption.
[✓] Checking Jupyter engine render....OK

[✓] Checking Julia installation...

[mcanouil]

resources is a project option, so it has to be in side _quarto.yml, not inside your YAML frontmatter.

• https://quarto.org/docs/websites/website-tools.html#site-resources

Have you looked at the documentation on external resources/assets in the shiny guide?

• https://quarto.org/docs/interactive/shiny/resources.html

resource-path is Pandoc's option passed to CLI --resource-path. It needs actual paths, not Globs (https://pandoc.org/MANUAL.html).

Now, the main issue is that the resources is not published alongside the Quarto document.
I'm not sure how the resources are selected here, but I would recommend you use _quarto.yml:

project:
  type: default
  resources:
    - ...

[cderv]

The issue is not tied up to dashboard format (except the weird layout issue).

That would simplify if we can have a reproducible example for publishing with shiny document.

I just know when we plugged shiny for Python in Quarto it was for dashboard mainly. So I don't know it works with non-dashboard and Shiny for Python.

We touch the preview context recently, so possibly this is a side effect for shiny document and quarto preview

[jimjam-slam]

Currently quarto publish posit-connect-cloud supports only static file and not shiny app.

I see in doc (https://quarto.org/docs/publishing/posit-connect-cloud.html) we only say

Use the quarto publish command to publish locally rendered static content.
which does not make that clear, but for now we didn't implemented non-static content, and other deploy method needs to be used.

Yes, that accords with my understanding now. When I deployed via quarto publish, none of the Shiny-related stuff worked, and (as @mcanouil noted) I observed it labelled on PCC as a 'Static document'. This is not the case when I deploy via a repo from the PCC website.

So I understand the issue is that following https://quarto.org/docs/interactive/shiny/resources.html does not work when publishing to posit connect cloud ?

Their how to guide does not say much... https://docs.posit.co/connect-cloud/how-to/python/shiny-python.html

That's my understanding, yes. I had been following the advice in https://quarto.org/docs/interactive/shiny/resources.html, but given it appears in the Shiny guide section, it might have been written with Shiny for R in mind, rather than Shiny for Python.

One illuminating aspect of my actual use case that the test case does not cover is that this appears to particularly be an issue with the Shiny serving aspect of static files. My actual use case is a Shiny for Python app (via a Quarto dashboard) that, among other things, can provide Quarto-rendered Type reports for users. The same images that don't appear in the app itself do appear in the rendered PDFs, so the files in question are clearly in the deployment bundle when I deploy via repo, even if they aren't served to users through the Shiny app.

To be sure this is an issue with posit connect cloud, one could try rsconnect-python package. https://docs.posit.co/rsconnect-python/

I might have to leave this to you, since this is an enterprise product and my client on this case is in academia.

In the mean time, our workaround will likely be to deploy the same branch to another JAMstack provider so that the image suit somewhere else and hardcode the URLs. If a fix is identified, we can revert this change down the line 😊

[jimjam-slam]

One last thing is a bit of a docs nomenclature issue: a Quarto document using Shiny (for R or Python) is generally referred to as an 'interactive document' (I assume to contrast against a static document), but PCC notes it will be billed as an app, and does not refer to it as a document at all (and also that I'm using 'Quarto' as the deployment framework on PCC, not Shiny — Quarto seems to handle the Shiny aspect just fine outside this specific issue, but it is a tricky user experience). Just some food for thought here!

[jimjam-slam]

Definitely something to look into. I can even have the image be loaded in quarto preview and positron.

Maybe something change with Shiny for Python and our dashboard integration.. I need to make time for that, but I am not sure when.

If anyone wants to dig into that with clear reproduction to verify

• Shiny for Python Dashboard document preview and render correctly in Quarto v1.9 and prerelease
• Publishing works with rsconnect-python or github deploy

I should note that I haven't encountered any other issues with dashboards and Shiny for Python in Quarto while working on this client project! I daresay you'd like a more comprehensive reprex for testing purposes, though.

[cderv]

One last thing is a bit of a docs nomenclature issue: a Quarto document using Shiny (for R or Python) is generally referred to as an 'interactive document' (I assume to contrast against a static document), but PCC notes it will be billed as an app, and does not refer to it as a document at all (and also that I'm using 'Quarto' as the deployment framework on PCC, not Shiny — Quarto seems to handle the Shiny aspect just fine outside this specific issue, but it is a tricky user experience). Just some food for thought here!

Thanks for the feedback. Are you suggesting we do make clearer that interactive document in Quarto are Shiny apps at the end ? We could. 🤔

In the mean time, our workaround will likely be to deploy the same branch to another JAMstack provider so that the image suit somewhere else and hardcode the URLs. If a fix is identified, we can revert this change down the line

So no method of deployment allows you to make this work ? quarto publish posit-connect-cloud won't work for sure (and I probably will add for 1.10 a stopper to avoid publish shiny doc when they are not supported yet).

One illuminating aspect of my actual use case that the test case does not cover is that this appears to particularly be an issue with the Shiny serving aspect of static files. My actual use case is a Shiny for Python app (via a Quarto dashboard) that, among other things, can provide Quarto-rendered Type reports for users. The same images that don't appear in the app itself do appear in the rendered PDFs, so the files in question are clearly in the deployment bundle when I deploy via repo, even if they aren't served to users through the Shiny app.

Is this a problem only in the deployed version ? when you do quarto preview or quarto serve ?
https://quarto.org/docs/dashboards/interactivity/shiny-python/running.html#command-line

Also for shiny for Python, things are a bit different that for Shiny for R. You can deploy your app without Quarto at all ! See https://quarto.org/docs/dashboards/interactivity/shiny-python/running.html#deployment

In fact, you don’t need Quarto at all to serve interactive documents, rather, you can just shiny run the application generated by quarto render:

quarto render example.qmd
shiny run app.py

So their could be a way to render your app locally, and then deploy it as a shiny app directly.

And this is why I was also thinking that rsconnect-python maybe better handle publishing of such doc.

[mcanouil]

@jimjam-slam

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