[#276] Merge repo with frostfs-api-go

Signed-off-by: Pavel Pogodaev <p.pogodaev@yadro.com>

api/rpc/client/call_options.go

@@ -0,0 +1,40 @@
+package client
+
+import (
+	"context"
+
+	"google.golang.org/grpc"
+)
+
+// CallOption is a messaging session option within Protobuf RPC.
+type CallOption func(*callParameters)
+
+type callParameters struct {
+	ctx    context.Context // nolint:containedctx
+	dialer func(context.Context, grpc.ClientConnInterface) error
+}
+
+func defaultCallParameters() *callParameters {
+	return &callParameters{
+		ctx: context.Background(),
+	}
+}
+
+// WithContext returns option to specify call context. If provided, all network
+// communications will be based on this context. Otherwise, context.Background()
+// is used.
+//
+// Context SHOULD NOT be nil.
+func WithContext(ctx context.Context) CallOption {
+	return func(prm *callParameters) {
+		prm.ctx = ctx
+	}
+}
+
+// WithDialer returns option to specify grpc dialer. If passed, it will be
+// called after the connection is successfully created.
+func WithDialer(dialer func(context.Context, grpc.ClientConnInterface) error) CallOption {
+	return func(prm *callParameters) {
+		prm.dialer = dialer
+	}
+}