Add cache compression.

README.md

@@ -180,7 +180,7 @@ Ban details will be stored in the `banned_users.json` file, which you can mount
 
 #### Healthcheck
 
-If you'd like the `/healthz` endpoint to perform actual check for the connectivity to the graphql endpoint - set the `HEALTHCHECK_GRAPHQL_URL` environment variable to the exact URL of the graphql endpoint. The query executed will be `query { __typename }` and if the response is not `200 OK` - the healthcheck will fail.
+If you'd like the `/healthz` endpoint to perform actual check for the connectivity to the graphql endpoint - set the `HEALTHCHECK_GRAPHQL_URL` environment variable to the exact URL of the graphql endpoint. The query executed will be `query { __typename }` and if the response is not `200 OK` - the healthcheck will fail. Remember that the endpoint is a full URL which you'd like to check, so it should include the protocol, host and path - for example `http://localhost:8080/v1/graphql` and it's NOT the same as value of `HOST_GRAPHQL` environment variable which should provide only the host, without path, ending with slash.
 
 #### Monitoring endpoint
 

cache/cache.go

@@ -1,6 +1,9 @@
 package libpack_cache
 
 import (
+	"bytes"
+	"compress/gzip"
+	"io"
 	"sync"
 	"time"
 )
@@ -46,15 +49,20 @@ func (c *Cache) Set(key string, value []byte, ttl time.Duration) {
 	defer c.Unlock()
 	expiresAt := time.Now().Add(ttl)
 
-	// Get a byte slice from the pool and ensure it's properly sized.
-	b := c.bytePool.Get().([]byte)
-	if cap(b) < len(value) {
-		b = make([]byte, len(value))
-	} else {
-		b = b[:len(value)]
+	compressedValue, err := c.compress(value)
+	if err != nil {
+		return
 	}
 
-	copy(b, value)
+	// Get a byte slice from the pool and ensure it's properly sized.
+	b := c.bytePool.Get().([]byte)
+	if cap(b) < len(compressedValue) {
+		b = make([]byte, len(compressedValue))
+	} else {
+		b = b[:len(compressedValue)]
+	}
+
+	copy(b, compressedValue)
 
 	entry := CacheEntry{
 		Value:     b,
@@ -71,10 +79,12 @@ func (c *Cache) Get(key string) ([]byte, bool) {
 	if !ok || entry.(CacheEntry).ExpiresAt.Before(time.Now()) {
 		return nil, false
 	}
+	compressedValue := entry.(CacheEntry).Value
+	value, err := c.decompress(compressedValue)
+	if err != nil {
+		return nil, false
+	}
 
-	// Copy the value from the byte slice.
-	value := make([]byte, len(entry.(CacheEntry).Value))
-	copy(value, entry.(CacheEntry).Value)
 	return value, true
 }
 
@@ -110,3 +120,26 @@ func (c *Cache) CleanExpiredEntries() {
 		return true
 	})
 }
+
+func (c *Cache) compress(data []byte) ([]byte, error) {
+	var buf bytes.Buffer
+	w := gzip.NewWriter(&buf)
+	_, err := w.Write(data)
+	if err != nil {
+		return nil, err
+	}
+	err = w.Close()
+	if err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}
+
+func (c *Cache) decompress(data []byte) ([]byte, error) {
+	r, err := gzip.NewReader(bytes.NewBuffer(data))
+	if err != nil {
+		return nil, err
+	}
+	defer r.Close()
+	return io.ReadAll(r)
+}

cache/cache_test.go

@@ -0,0 +1,112 @@
+package libpack_cache
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/suite"
+)
+
+type CacheTestSuite struct {
+	suite.Suite
+}
+
+func (suite *CacheTestSuite) SetupTest() {
+}
+
+func TestCachingTestSuite(t *testing.T) {
+	suite.Run(t, new(CacheTestSuite))
+}
+
+func (suite *CacheTestSuite) Test_New() {
+	suite.T().Run("should return a new cache", func(t *testing.T) {
+		cache := New(2 * time.Second)
+		suite.NotNil(cache)
+	})
+}
+
+func (suite *CacheTestSuite) Test_CacheUse() {
+	cache := New(30 * time.Second)
+	tests := []struct {
+		name        string
+		cache_value string
+	}{
+		{
+			name:        "test1",
+			cache_value: "test1-123",
+		},
+		{
+			name:        "test2",
+			cache_value: "test2-123",
+		},
+	}
+	for _, tt := range tests {
+		suite.T().Run(tt.name, func(t *testing.T) {
+			cache.Set(tt.name, []byte(tt.name), 5*time.Second)
+			c, ok := cache.Get(tt.name)
+			suite.Equal(true, ok)
+			suite.Equal(tt.name, string(c))
+		})
+	}
+}
+
+func (suite *CacheTestSuite) Test_CacheDelete() {
+	cache := New(30 * time.Second)
+	tests := []struct {
+		name        string
+		cache_value string
+	}{
+		{
+			name:        "test1",
+			cache_value: "test1-123",
+		},
+		{
+			name:        "test2",
+			cache_value: "test2-123",
+		},
+	}
+	for _, tt := range tests {
+		suite.T().Run(tt.name, func(t *testing.T) {
+			cache.Set(tt.name, []byte(tt.name), 5*time.Second)
+			c, ok := cache.Get(tt.name)
+			suite.Equal(true, ok)
+			suite.Equal(tt.name, string(c))
+			cache.Delete(tt.name)
+			c, ok = cache.Get(tt.name)
+			suite.Equal(false, ok)
+			suite.Equal("", string(c))
+		})
+	}
+}
+
+func (suite *CacheTestSuite) Test_CacheExpire() {
+	cache := New(30 * time.Second)
+	tests := []struct {
+		name        string
+		cache_value string
+		ttl         time.Duration
+	}{
+		{
+			name:        "test1",
+			cache_value: "test1-123",
+			ttl:         2 * time.Second,
+		},
+		{
+			name:        "test2",
+			cache_value: "test2-123",
+			ttl:         5 * time.Second,
+		},
+	}
+	for _, tt := range tests {
+		suite.T().Run(tt.name, func(t *testing.T) {
+			cache.Set(tt.name, []byte(tt.name), tt.ttl)
+			c, ok := cache.Get(tt.name)
+			suite.Equal(true, ok)
+			suite.Equal(tt.name, string(c))
+			time.Sleep(tt.ttl)
+			c, ok = cache.Get(tt.name)
+			suite.Equal(false, ok)
+			suite.Equal("", string(c))
+		})
+	}
+}