Dynamic values in dropdown menu in form.yml

[AshASML]

Hello

I’m trying to create a dropdown in jupyter lab app which will show the existing conda environment for the users to select and activate it before starting the session.
I’m following Dynamic Behavior - Issue - Get Help - Open OnDemand although Im getting some error when loading the form . I dont think it is ruby error because it runs well as a ruby file . I believe it has to do something with ruby code in .yml (form.yml) . I’d really appreciate if you can take a look and tell me if there is something I doing wrong with ? Please advise. Thanks !

Code:

<%-
require ‘open3’
cmd=“/hpc/apps/anaconda3/2022.5/bin/conda env list | awk ‘{print $1}’ | tail -n +3”
stdout, stderr, status = Open3.capture3(‘bash’,stdin_data: cmd)
conda_envs =
if status.success?
stdout.split(“\n”).each do |env|
conda_envs.append(env)
end
puts conda_envs
else
abort ‘error: could not execute command’
end
-%>

cluster: “pbs_pro”

attributes:
modules: “singularity/3.3-rhel7”
extra_jupyter_args: “”
memory:
widget: “number_field”
max: 100
min: 4
step: 1
label: “Memory (GB)”
conda_env:
widget: “select”
label: “Conda environment”
options:
<%- conda_envs.each do |h| %>
- <%= h %>
<%- end %>

form:

• modules
• extra_jupyter_args
• bc_queue
• bc_num_hours
• bc_num_slots
• bc_email_on_started
• memory
• conda_env

Error I m getting is

[jeff.ohrstrom]

There is something wrong with the resulting YAML, though I can’t tell because the formatting is off.

To format yaml in discourse you have to wrap it in backticks and specify yaml.

So something like this

```yaml
here: is some valid yaml
```

results in

here: is some valid yaml

But in any case - the error indicates the line and column where the error occurred, so it’s some help.

[AshASML]

Please find below corrected version …
I dont believe this is the syntax error on line 4. The same code works fine as ruby file . But , whenever I try to integrate it in .yml file it throws such error .
Can you please take a look at it now ? Thanks !

<%-
require 'open3'
cmd="/hpc/shared/apps/anaconda3/2022.5/bin/conda env list  | awk '{print $1}' | tail -n +3"
stdout, stderr, status = Open3.capture3('bash',stdin_data: cmd)
conda_envs = []
if status.success?
  stdout.split("\n").each do |env|
    conda_envs.push(env)
  end
  puts conda_envs
else
  abort 'error: could not execute command'
end
-%>

---

cluster: "pbs"

attributes:
  modules: "singularity/3.3-rhel7"
  extra_jupyter_args: ""
  memory:
    widget: "number_field"
    max: 100
    min: 4
    step: 1
    label: "Memory (GB)"
widget: “select”
    label: “Conda environment”
   options:
   <%- conda_envs.each do |h| %>
  - <%= h %>
   <%- end %>


form:
  - modules
  - extra_jupyter_args
  - bc_queue
  - bc_num_hours
  - bc_num_slots
  - bc_email_on_started
  - memory
  - conda_envs

[jeff.ohrstrom]

I go this working in this file. You’ll need to change the cluster and conda location as those are specific to my system.

You have a few issues:

• First you need the yml.erb extension. The system was reading this file as straight YAML which it wasn’t. Because it had no erb extension - it did not process it correctly.
• Secondly - you have issues with what I assume is conda_envs. You see your widget is not indented correctly along with other fields that pertain to conda_envs.

form.yml.erb.txt (808 Bytes)

I was using this command to verify

erb -r open3 -T - form.yml.erb  | ruby -ryaml -e "p YAML.load(STDIN.read)"

[AshASML]

Hi Jeff ,

Thanks . I believe I did many trials which explains the typo in second indention. Well , having no .erb extension was the problem . Thank you so much ! I could’nt have figure it out without your assistance . Appreciate it