---

name: field-name-mapper description: Map field names between Web API and Android/iOS when they differ. Fix issues where Android sends 'name' but API expects 'certName', or API returns 'project_name' but Android expects 'projectName'. Handle both request and response field mapping. allowed-tools: Read, Grep, Edit

Field Name Mapper

Purpose

Fix field name mismatches between platforms when:

• Android sends field with different name than API expects
• API returns field with different name than mobile expects
• snake_case vs camelCase conversion issues

Common Patterns

Android Request Field Differs from API

Problem: Android sends name, API expects certName

Android Model:

Copydata class CreateCertificationRequest(
    val name: String,  // Android convention
    val certificateNumber: String?
)

API Expects:

Copyconst { certName, certNumber } = body  // Different names!

Fix in API - Accept both:

Copyconst {
    certName,
    name,  // Android alias
    certNumber,
    certificateNumber  // Android alias
} = body

// Use whichever was provided
const finalCertName = certName || name
const finalCertNumber = certNumber || certificateNumber

API Response Field Differs from Mobile Model

Problem: API returns certName, Android expects name

API Returns:

Copyreturn { certName: 'Test Cert', certNumber: '123' }

Android Expects:

Copydata class Certification(
    val name: String,  // Expects 'name', not 'certName'
    val certificateNumber: String?
)

Fix in API - Transform response:

Copyreturn {
    name: cert.certName,  // Map to Android field name
    certificateNumber: cert.certNumber
}

Field Mapping Reference

Common Mappings (Prisma → Mobile)

Date Field Patterns

Prisma returns Date objects, serialize to ISO string:

Copy// Prisma returns: Date object
// Android expects: "2024-01-15" or "2024-01-15T10:30:00Z"

return {
    date: record.date.toISOString().split('T')[0],  // Date only
    createdAt: record.createdAt.toISOString()  // Full datetime
}

Accepting Multiple Field Names

Pattern for accepting both web and mobile field names:

Copyconst body = await request.json()
const {
    // Web naming
    certName,
    certNumber,

    // Mobile naming (aliases)
    name,
    certificateNumber,

    // Date fields - accept both
    date,
    scheduledDate,  // Android might send this

    // Title vs Name
    title,
    listName  // Web might use this
} = body

// Resolve to final values
const finalName = certName || name
const finalNumber = certNumber || certificateNumber
const finalDate = date || scheduledDate
const finalTitle = title || listName

Transform Function Pattern

Create transform functions for consistent mobile responses:

Copyfunction transformCertification(cert: PrismaCert): MobileCert {
    return {
        id: cert.id,
        name: cert.certName,  // Prisma → Mobile mapping
        certificateNumber: cert.certNumber,
        issuingAuthority: cert.issuingAuthority,
        issueDate: cert.issueDate?.toISOString().split('T')[0] ?? null,
        expiryDate: cert.expiryDate?.toISOString().split('T')[0] ?? null,
        status: cert.status,
        createdAt: cert.createdAt.toISOString()
    }
}

// Use in API response
return NextResponse.json(transformCertification(cert))

Debugging Field Mismatches

Check What Android Sends

Look at server logs for request body:

Copyconsole.log('Request body:', JSON.stringify(body, null, 2))

Check What API Returns

Compare API response to Android model:

Copy# Make API call directly
curl -X GET http://localhost:3000/api/certifications \
    -H "Authorization: Bearer $TOKEN" | jq

Check Android Model Requirements

Copy# Find Android model
grep -A 30 "data class Certification" apps/android/**/model/*.kt

Look for:

• Fields without default values (required)
• @SerialName annotations (expect snake_case)
• Field names differ from Prisma

Quick Fix Checklist

When fixing a field mismatch:

1. Identify the exact field name mismatch
2. Check if API needs to accept alias in request
3. Check if API needs to rename in response
4. Update API to handle both names
5. Add transform function if multiple fields differ
6. Test with actual mobile request