| name | golem-fix-missing-ns |
| description | Validate that all module input/output IDs are properly namespaced.
Triggers on:
- "check my modules for missing ns"
- "find missing ns in modules"
- "validate module namespaces"
Do not trigger on:
- when the user is not working inside a golem app
|
Check for Missing ns() in Modules
Validate that all module input/output IDs are properly namespaced.
Why Namespacing Matters
In Shiny modules, all input and output IDs must be namespaced using the ns() function. This prevents ID conflicts when the same module is used multiple times in an app.
Correct vs Incorrect
✅ Correct
mod_analytics_ui <- function(id) {
ns <- NS(id)
tagList(
selectInput(
ns("type_filter"),
label = NULL,
choices = c("All", "None")
)
)
}
❌ Incorrect
mod_analytics_ui <- function(id) {
ns <- NS(id)
tagList(
selectInput(
"type_filter",
label = NULL,
choices = c("All", "None")
)
)
}
What to Check
In Module UI Functions
- All input IDs:
textInput(), selectInput(), actionButton(), etc.
- All output IDs:
plotOutput(), tableOutput(), uiOutput(), etc.
- All input control IDs used in
ns() calls
In Module Server Functions
- JavaScript handler IDs that reference the module namespace
observeEvent(input$...) references
output$... definitions
renderUI() generated element IDs
Places to Look
- Any file starting with
mod_ in the R/ directory
- Both UI and server functions within modules
How Claude Checks
-
Locate all IDs in module files (files starting with mod_)
- Search for common patterns:
Input(), Output(), input/output IDs
-
Verify namespacing by checking each ID is wrapped in ns()
- Exception: Only the first
NS(id) definition doesn't need wrapping
-
Report findings
- If all IDs are properly namespaced: ✅ All good
- If missing IDs found: ❌ List them and ask for permission to fix
-
Fix if approved
- Wrap missing IDs in
ns()
- Preserve code structure and formatting
Common Mistakes
| Mistake | Fix |
|---|
selectInput("myid", ...) | selectInput(ns("myid"), ...) |
plotOutput("plot") | plotOutput(ns("plot")) |
observeEvent(input$button) | observeEvent(input$submit, ...) with ID properly namespaced |
uiOutput("dynamic") | uiOutput(ns("dynamic")) |
When to Run
- After creating or modifying module UI functions
- Before running
devtools::check()
- When adding new inputs/outputs to modules
- Before deploying to production
Example Workflow
User: Check my modules for missing ns()
Claude:
1. Scans all mod_*.R files
2. Identifies 3 missing ns() wrappings
3. Shows the issues with line numbers
4. Asks: "Should I fix these?"
User: Yes, fix them
Claude:
- Updates the files
- Runs the check again to verify
- Confirms: "All fixed! ✅"
Notes
- This check is for UI and reactive server code, not data processing functions
- Only module files (
mod_*.R) need this check
- Regular functions (
fct_*.R, utils_*.R) don't need namespace wrapping
- Module server functions are called with the module ID, which handles the namespacing