[#291] container: Add ListStream method

Signed-off-by: Ekaterina Lebedeva <ekaterina.lebedeva@yadro.com>

client/container_list_stream.go

@@ -0,0 +1,182 @@
+package client
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/container"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/refs"
+	rpcapi "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/rpc"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/rpc/client"
+	v2session "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/session"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/api/signature"
+	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
+	cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/session"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/user"
+)
+
+// PrmContainerListStream groups parameters of ContainerListStream operation.
+type PrmContainerListStream struct {
+	XHeaders []string
+
+	Account user.ID
+
+	Session *session.Container
+}
+
+// SetAccount sets identifier of the FrostFS account to list the containers.
+// Required parameter.
+//
+// Deprecated: Use PrmContainerListStream.Account instead.
+func (x *PrmContainerListStream) SetAccount(id user.ID) {
+	x.Account = id
+}
+
+func (x *PrmContainerListStream) buildRequest(c *Client) (*container.ListStreamRequest, error) {
+	if x.Account.IsEmpty() {
+		return nil, errorAccountNotSet
+	}
+
+	var ownerV2 refs.OwnerID
+	x.Account.WriteToV2(&ownerV2)
+
+	reqBody := new(container.ListStreamRequestBody)
+	reqBody.SetOwnerID(&ownerV2)
+
+	var meta v2session.RequestMetaHeader
+	writeXHeadersToMeta(x.XHeaders, &meta)
+
+	if x.Session != nil {
+		var tokv2 v2session.Token
+		x.Session.WriteToV2(&tokv2)
+
+		meta.SetSessionToken(&tokv2)
+	}
+
+	var req container.ListStreamRequest
+	req.SetBody(reqBody)
+	c.prepareRequest(&req, &meta)
+	return &req, nil
+}
+
+type ResContainerListStream struct {
+	statusRes
+}
+
+type ContainerListReader struct {
+	client          *Client
+	cancelCtxStream context.CancelFunc
+	err             error
+	res             ResContainerListStream
+	stream          interface {
+		Read(resp *container.ListStreamResponse) error
+	}
+	tail []refs.ContainerID
+}
+
+func (x *ContainerListReader) Read(buf []cid.ID) (int, bool) {
+	if len(buf) == 0 {
+		panic("empty buffer in ContainerListReader.ReadList")
+	}
+
+	read := copyCnrIDBuffers(buf, x.tail)
+	x.tail = x.tail[read:]
+
+	if len(buf) == read {
+		return read, true
+	}
+
+	for {
+		var resp container.ListStreamResponse
+		x.err = x.stream.Read(&resp)
+		if x.err != nil {
+			return read, false
+		}
+
+		x.res.st, x.err = x.client.processResponse(&resp)
+		if x.err != nil || !apistatus.IsSuccessful(x.res.st) {
+			return read, false
+		}
+
+		// read new chunk of objects
+		ids := resp.GetBody().GetContainerIDs()
+		if len(ids) == 0 {
+			// just skip empty lists since they are not prohibited by protocol
+			continue
+		}
+
+		ln := copyCnrIDBuffers(buf[read:], ids)
+		read += ln
+
+		if read == len(buf) {
+			// save the tail
+			x.tail = append(x.tail, ids[ln:]...)
+
+			return read, true
+		}
+	}
+}
+
+func copyCnrIDBuffers(dst []cid.ID, src []refs.ContainerID) int {
+	var i int
+	for ; i < len(dst) && i < len(src); i++ {
+		_ = dst[i].ReadFromV2(src[i])
+	}
+	return i
+}
+
+func (x *ContainerListReader) Iterate(f func(cid.ID) bool) error {
+	buf := make([]cid.ID, 1)
+
+	for {
+		// Do not check first return value because `len(buf) == 1`,
+		// so false means nothing was read.
+		_, ok := x.Read(buf)
+		if !ok {
+			res, err := x.Close()
+			if err != nil {
+				return err
+			}
+			return apistatus.ErrFromStatus(res.Status())
+		}
+		if f(buf[0]) {
+			return nil
+		}
+	}
+}
+
+func (x *ContainerListReader) Close() (*ResContainerListStream, error) {
+	defer x.cancelCtxStream()
+
+	if x.err != nil && !errors.Is(x.err, io.EOF) {
+		return nil, x.err
+	}
+
+	return &x.res, nil
+}
+
+func (c *Client) ContainerListInit(ctx context.Context, prm PrmContainerListStream) (*ContainerListReader, error) {
+	req, err := prm.buildRequest(c)
+	if err != nil {
+		return nil, err
+	}
+
+	err = signature.SignServiceMessage(&c.prm.Key, req)
+	if err != nil {
+		return nil, fmt.Errorf("sign request: %w", err)
+	}
+
+	var r ContainerListReader
+	ctx, r.cancelCtxStream = context.WithCancel(ctx)
+
+	r.stream, err = rpcapi.ListContainersStream(&c.c, req, client.WithContext(ctx))
+	if err != nil {
+		return nil, fmt.Errorf("open stream: %w", err)
+	}
+	r.client = c
+
+	return &r, nil
+}