wavelet init

Wavelet/pkg/cache/ram/cache.go

@@ -0,0 +1,73 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+// Package ram provides a thin wrapper around Otter v2 for process-local caching.
+package ram
+
+import (
+	"github.com/maypok86/otter/v2"
+)
+
+const defaultMaximumSize = 256
+
+// Options configures a RAM cache instance.
+type Options struct {
+	// MaximumSize bounds the number of entries. Zero uses a small default.
+	MaximumSize int
+}
+
+// Cache is a concurrency-safe in-memory cache backed by Otter.
+type Cache[K comparable, V any] struct {
+	inner *otter.Cache[K, V]
+}
+
+// New creates a RAM cache from the provided options.
+func New[K comparable, V any](opts Options) (*Cache[K, V], error) {
+	maximumSize := opts.MaximumSize
+	if maximumSize == 0 {
+		maximumSize = defaultMaximumSize
+	}
+
+	inner, err := otter.New(&otter.Options[K, V]{
+		MaximumSize: maximumSize,
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	return &Cache[K, V]{inner: inner}, nil
+}
+
+// MustNew creates a RAM cache and panics when configuration is invalid.
+func MustNew[K comparable, V any](opts Options) *Cache[K, V] {
+	cache, err := New[K, V](opts)
+	if err != nil {
+		panic(err)
+	}
+	return cache
+}
+
+// GetIfPresent returns the cached value when present.
+func (c *Cache[K, V]) GetIfPresent(key K) (V, bool) {
+	return c.inner.GetIfPresent(key)
+}
+
+// Set stores a value in the cache.
+func (c *Cache[K, V]) Set(key K, value V) {
+	c.inner.Set(key, value)
+}
+
+// Invalidate removes one entry from the cache.
+func (c *Cache[K, V]) Invalidate(key K) {
+	c.inner.Invalidate(key)
+}
+
+// InvalidateAll removes every entry from the cache.
+func (c *Cache[K, V]) InvalidateAll() {
+	c.inner.InvalidateAll()
+}
+
+// EstimatedSize returns the approximate number of cached entries.
+func (c *Cache[K, V]) EstimatedSize() int {
+	return c.inner.EstimatedSize()
+}

Wavelet/pkg/cache/ram/cache_test.go

@@ -0,0 +1,38 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package ram
+
+import "testing"
+
+func TestCacheSetGetInvalidate(t *testing.T) {
+	cache := MustNew[string, int](Options{MaximumSize: 8})
+
+	cache.Set("count", 3)
+
+	got, ok := cache.GetIfPresent("count")
+	if !ok {
+		t.Fatal("GetIfPresent(count) ok = false, want true")
+	}
+	if got != 3 {
+		t.Fatalf("GetIfPresent(count) = %d, want %d", got, 3)
+	}
+
+	cache.Invalidate("count")
+	if _, ok := cache.GetIfPresent("count"); ok {
+		t.Fatal("GetIfPresent(count) after Invalidate ok = true, want false")
+	}
+}
+
+func TestCacheInvalidateAll(t *testing.T) {
+	cache := MustNew[string, string](Options{MaximumSize: 8})
+
+	cache.Set("a", "1")
+	cache.Set("b", "2")
+
+	cache.InvalidateAll()
+
+	if cache.EstimatedSize() != 0 {
+		t.Fatalf("EstimatedSize() after InvalidateAll = %d, want 0", cache.EstimatedSize())
+	}
+}