[#80] objectwriter: Allow custimize maxChunkLen

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

client/object_put.go

@@ -25,6 +25,7 @@ type PrmObjectPutInit struct {
 	copyNum     []uint32
 	key         *ecdsa.PrivateKey
 	meta        v2session.RequestMetaHeader
+	maxChunkLen int
 }
 
 // SetCopiesNumber sets number of object copies that is enough to consider put successful.
@@ -39,6 +40,15 @@ func (x *PrmObjectPutInit) SetCopiesNumberByVectors(copiesNumbers []uint32) {
 	x.copyNum = copiesNumbers
 }
 
+// SetGRPCPayloadChunkLen sets maximum chunk length value for gRPC Put request.
+// Maximum chunk length restricts maximum byte length of the chunk
+// transmitted in a single stream message. It depends on
+// server settings and other message fields.
+// If not specified or negative value set, default value of 3MiB will be used.
+func (x *PrmObjectPutInit) SetGRPCPayloadChunkLen(v int) {
+	x.maxChunkLen = v
+}
+
 // ResObjectPut groups the final result values of ObjectPutInit operation.
 type ResObjectPut struct {
 	statusRes
@@ -74,6 +84,8 @@ type ObjectWriter struct {
 	req       v2object.PutRequest
 	partInit  v2object.PutObjectPartInit
 	partChunk v2object.PutObjectPartChunk
+
+	maxChunkLen int
 }
 
 // UseKey specifies private key to sign the requests.
@@ -143,15 +155,8 @@ func (x *ObjectWriter) WritePayloadChunk(chunk []byte) bool {
 	}
 
 	for ln := len(chunk); ln > 0; ln = len(chunk) {
-		// maxChunkLen restricts maximum byte length of the chunk
+		if ln > x.maxChunkLen {
-		// transmitted in a single stream message. It depends on
+			ln = x.maxChunkLen
-		// server settings and other message fields, but for now
-		// we simply assume that 3MB is large enough to reduce the
-		// number of messages, and not to exceed the limit
-		// (4MB by default for gRPC servers).
-		const maxChunkLen = 3 << 20
-		if ln > maxChunkLen {
-			ln = maxChunkLen
 		}
 
 		// we deal with size limit overflow above, but there is another case:
@@ -263,6 +268,11 @@ func (c *Client) ObjectPutInit(ctx context.Context, prm PrmObjectPutInit) (*Obje
 	w.stream = stream
 	w.partInit.SetCopiesNumber(prm.copyNum)
 	w.req.SetBody(new(v2object.PutRequestBody))
+	if prm.maxChunkLen > 0 {
+		w.maxChunkLen = prm.maxChunkLen
+	} else {
+		w.maxChunkLen = 3 << 20
+	}
 	c.prepareRequest(&w.req, &prm.meta)
 
 	return &w, nil