Merge pull request #766 from raj-prince/add_storage_handle_file

Adding API to Create Storage Client Handle

internal/storage/storage_handle.go

@@ -0,0 +1,70 @@
+package storage
+
+import (
+	"crypto/tls"
+	"fmt"
+	"net/http"
+	"time"
+
+	"cloud.google.com/go/storage"
+	"golang.org/x/net/context"
+	"golang.org/x/oauth2"
+	"google.golang.org/api/option"
+)
+
+type storageClient struct {
+	client *storage.Client
+}
+
+type storageClientConfig struct {
+	disableHTTP2        bool
+	maxConnsPerHost     int
+	maxIdleConnsPerHost int
+	tokenSrc            oauth2.TokenSource
+	timeOut             time.Duration
+}
+
+// NewStorageHandle returns the handle of Go storage client containing
+// customized http client. We can configure the http client using the
+// storageClientConfig parameter.
+func NewStorageHandle(ctx context.Context,
+	clientConfig storageClientConfig) (sh *storageClient, err error) {
+	var transport *http.Transport
+	// Disabling the http2 makes the client more performant.
+	if clientConfig.disableHTTP2 {
+		transport = &http.Transport{
+			MaxConnsPerHost:     clientConfig.maxConnsPerHost,
+			MaxIdleConnsPerHost: clientConfig.maxIdleConnsPerHost,
+			// This disables HTTP/2 in transport.
+			TLSNextProto: make(
+				map[string]func(string, *tls.Conn) http.RoundTripper,
+			),
+		}
+	} else {
+		// For http2, change in MaxConnsPerHost doesn't affect the performance.
+		transport = &http.Transport{
+			DisableKeepAlives: true,
+			MaxConnsPerHost:   clientConfig.maxConnsPerHost,
+			ForceAttemptHTTP2: true,
+		}
+	}
+
+	// Custom http client for Go Client.
+	httpClient := &http.Client{
+		Transport: &oauth2.Transport{
+			Base:   transport,
+			Source: clientConfig.tokenSrc,
+		},
+		Timeout: clientConfig.timeOut,
+	}
+
+	var sc *storage.Client
+	sc, err = storage.NewClient(ctx, option.WithHTTPClient(httpClient))
+	if err != nil {
+		err = fmt.Errorf("go storage client creation failed: %w", err)
+		return
+	}
+
+	sh = &storageClient{sc}
+	return
+}

internal/storage/storage_handle_test.go

@@ -0,0 +1,53 @@
+package storage
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"golang.org/x/oauth2"
+)
+
+func invokeAndVerifyStorageHandle(t *testing.T, sc storageClientConfig) {
+	handleCreated, err := NewStorageHandle(context.Background(), sc)
+
+	if err != nil {
+		t.Errorf("Handle creation failure")
+	}
+	if nil == handleCreated {
+		t.Fatalf("Storage handle is null")
+	}
+	if nil == handleCreated.client {
+		t.Fatalf("Storage client handle is null")
+	}
+}
+
+func TestNewStorageHandleHttp2Disabled(t *testing.T) {
+	sc := storageClientConfig{disableHTTP2: true,
+		maxConnsPerHost:     10,
+		maxIdleConnsPerHost: 100,
+		tokenSrc:            oauth2.StaticTokenSource(&oauth2.Token{}),
+		timeOut:             800 * time.Millisecond}
+
+	invokeAndVerifyStorageHandle(t, sc)
+}
+
+func TestNewStorageHandleHttp2Enabled(t *testing.T) {
+	sc := storageClientConfig{disableHTTP2: false,
+		maxConnsPerHost:     10,
+		maxIdleConnsPerHost: 100,
+		tokenSrc:            oauth2.StaticTokenSource(&oauth2.Token{}),
+		timeOut:             800 * time.Millisecond}
+
+	invokeAndVerifyStorageHandle(t, sc)
+}
+
+func TestNewStorageHandleWithZeroMaxConnsPerHost(t *testing.T) {
+	sc := storageClientConfig{disableHTTP2: true,
+		maxConnsPerHost:     0,
+		maxIdleConnsPerHost: 100,
+		tokenSrc:            oauth2.StaticTokenSource(&oauth2.Token{}),
+		timeOut:             800 * time.Millisecond}
+
+	invokeAndVerifyStorageHandle(t, sc)
+}