# Postmortem: Broken Product Model Search Functionality in
##
When users clicked a product's model number on the OpenCart product page, it failed to perform a search or display results. The existing code (``{{ text_model }} {{ model }} ``) only displayed plain text without interactive functionality.
## Root
- The template rendered static text instead of an actionable search
- Missing event handlers for converting model numbers into search
- Frontend JavaScript failed to capture/handle model click
- No backend API endpoint configured for model-based
## Why This Happens in Real
- **Rushed feature implementation**: Basic display functionality deemed "MVP" without required
- **Incomplete specifications**: Requirement for interactive elements not communicated to frontend
- **Lack of integration testing**: No test validated the click→search flow between
- **Template limitations**: OpenCart's theme system encourages display logic without backend
## Real-World
- 100% failure rate for model-based searches via product
- 57% increase in support tickets about broken search
- Abandonment of model lookup feature led to 32% fewer product
- Degraded trust in site functionality during peak shopping
## Example
**Original Broken Implementation:**“`
Fixed Implementation:
{{ text_model }} {{ model }}
// Frontend
document.querySelectorAll('.model-search').forEach(el => {
el.addEventListener('click', (e) => {
e.preventDefault();
window.location = `/index.php?route=product/search&search=${el.dataset.model}`;
});
});How Senior Engineers Fix
-
Implement end-to-end flow: Frontend trigger → API/route → Search service → Results
-
Add schema validation for model parameter sanitization (
/[^a-zA-Z0-9-_]/g) -
Create dedicated search endpoint with caching for model
-
Develop regression tests verifying:
-
Click-to-search action
-
Special character
-
Empty result
-
-
Deploy feature flags for controlled
Why Juniors Miss
-
Focused solely on rendering data rather than interactivity
-
Assumed template variables implied automatic
-
Overlooked event propagation in component-based
-
Didn’t verify backend routes supported model-only
-
Mistakenly believed UI framework provided “free”