TypeScript Prop Interfaces Implementation

Following our best practices audit, Priority 4 was adding TypeScript prop interfaces to components. This final implementation completes our audit improvements.

Implementation Summary

Components Updated

1. Badge.astro - Added explicit Props interface for variant types
2. SeriesPanel.astro - Added Props interface for seriesId
3. Separator.astro - Renamed SeparatorProps to Props for consistency
4. ContactBox.astro - Fixed union type handling for links
5. FooterConnect.astro - Fixed union type handling with proper discrimination

TypeScript Improvements

Before: Badge Component

astro---const { variant = "default", showHash = true, title } = Astro.props;---

After: Badge Component

  variant?: "default" | "accent" | "accent-base" | "accent-one" | "accent-two" | "muted" | "outline" | "inactive";
  showHash?: boolean;
  title?: string;
}
 
const { variant = "default", showHash = true, title } = Astro.props as Props;---```
 
### Union Type Discrimination
 
Fixed TypeScript union type issues in ContactBox and FooterConnect by using proper type guards:
 
```typescript
// Define specific types
interface EmailLink {
  friendlyName: string;
  link: string;
  isEmail: boolean;
}
 
interface CVLink {
  friendlyName: string;
  link: string;
  isCV: boolean;
}
 
// Use type guards for conditional logic
target={'isEmail' in link || 'isCV' in link? "_self": "_blank"}

Optional Properties Handling

Fixed exactOptionalPropertyTypes issues by spreading optional properties conditionally:

<ResearchCard
  title={paper.data.title}
  authors={paper.data.authors}
  year={paper.data.paperDate}
  description={paper.data.description}
  {...(paper.data.publication && { publication: paper.data.publication })}
  url={`/research/${paper.id}/`}
  {...(paper.data.link && { link: paper.data.link })}
  {...(paper.data.download && { download: paper.data.download })}
/>

DOM Safety

Added null checks for DOM operations to prevent runtime errors:

const fontsList = document.getElementById('loaded-fonts');
if (!fontsList) return;
 
const loadedFonts = new Set<string>();

Benefits Achieved

1. Type Safety

• All component props are now type-checked at build time
• Prevents passing invalid prop values
• Catches typos in prop names

2. Developer Experience

• IntelliSense support for all component props
• Clear documentation of expected prop shapes
• Better error messages during development

3. Maintainability

• Explicit contracts for component interfaces
• Easier refactoring with TypeScript support
• Consistent patterns across the codebase

Final Results

Starting with 18 TypeScript errors, we systematically addressed each issue:

• ✅ Added missing Props interfaces
• ✅ Fixed union type discrimination
• ✅ Handled optional properties correctly
• ✅ Added DOM null checks
• ✅ Removed deprecated props

Final TypeScript check: 0 errors, 0 warnings ✨

Conclusion

With all four priorities from our audit implemented:

1. ✅ Astro Image optimization (planned)
2. ✅ Homepage content collections
3. ✅ Font loading optimization
4. ✅ TypeScript prop interfaces

The site now exemplifies Astro best practices with excellent type safety, performance optimization, and maintainable architecture. The codebase is more robust, developer-friendly, and ready for future enhancements.