BAB 52. CACHING STRATEGY

Tujuan

Caching digunakan untuk mengurangi beban database, mempercepat response API, dan meningkatkan skalabilitas sistem saat jumlah pengguna bertambah.

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Teknologi

Environment	Driver	Keterangan
Development	file	Mudah di-debug, tidak perlu Redis
Production	redis	Performa tinggi, mendukung TTL dan pub/sub

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Objek yang Di-cache

Objek	Cache Key	TTL	Invalidasi
Profil pengguna	user:{id}	10 menit	Saat profil diupdate
Daftar skill	skills:all	60 menit	Saat skill master berubah
Mata pelajaran	subjects:school:{id}	24 jam	Saat admin update mapel
Leaderboard	leaderboard:school:{id}	5 menit	Setelah SIS dihitung ulang
Dashboard statistik	dashboard:student:{id}	5 menit	Setelah sesi selesai
Academic year aktif	academic_year:school:{id}	60 menit	Saat admin ganti tahun ajaran
Data sekolah	school:{id}	60 menit	Saat admin update data sekolah

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Arsitektur Cache

flowchart LR
    C["📱 Client"] --> API["🌐 Laravel API"]
    API --> CACHE{{"🗄️ Redis Cache"}}
    CACHE -->|"Cache Hit ✅"| R1["⚡ Response\n(cepat)"]
    CACHE -->|"Cache Miss ❌"| DB[("💾 MySQL")]
    DB --> CACHE
    CACHE --> R2["📤 Response\n(disimpan ke cache)"]

    style CACHE fill:#dc2626,color:#fff

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Implementasi di Laravel

// app/Modules/Students/Services/StudentService.php

public function getProfile(int $studentId): Student
{
    return Cache::remember(
        "user:{$studentId}",
        now()->addMinutes(10),
        fn () => Student::with(['user', 'classroom', 'skills'])->findOrFail($studentId)
    );
}

public function updateProfile(int $studentId, array $data): Student
{
    $student = $this->repository->update($studentId, $data);

    // Invalidasi cache setelah update
    Cache::forget("user:{$studentId}");

    return $student;
}

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Leaderboard Cache

// app/Modules/Leaderboard/Services/LeaderboardService.php

public function getLeaderboard(int $schoolId): Collection
{
    return Cache::remember(
        "leaderboard:school:{$schoolId}",
        now()->addMinutes(5),
        fn () => Student::where('school_id', $schoolId)
            ->orderByDesc('sis_score')
            ->limit(100)
            ->get()
    );
}

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Strategi Invalidasi Cache

Cache dihapus secara otomatis via Laravel Observer saat data berubah:

// app/Modules/Students/Observers/StudentObserver.php

class StudentObserver
{
    public function updated(Student $student): void
    {
        Cache::forget("user:{$student->id}");
        Cache::forget("leaderboard:school:{$student->school_id}");
        Cache::forget("dashboard:student:{$student->id}");
    }
}

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Keuntungan Caching

Keuntungan	Dampak
Kurangi query DB	Database tidak kelebihan beban
Response lebih cepat	User experience lebih baik
Scalable	Mendukung banyak pengguna bersamaan
Leaderboard real-time semu	Update 5 menit sekali, terasa real-time