From 1566f74d8c4351d3f49911a9cdceb7203629b13d Mon Sep 17 00:00:00 2001
From: Airat Arifullin <a.arifullin@yadro.com>
Date: Fri, 2 Aug 2024 11:39:58 +0300
Subject: [PATCH] [#XX] client: `Patch`

Signed-off-by: Airat Arifullin <a.arifullin@yadro.com>
---
 client/object_patch.go | 165 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 165 insertions(+)
 create mode 100644 client/object_patch.go

diff --git a/client/object_patch.go b/client/object_patch.go
new file mode 100644
index 0000000..13c13fb
--- /dev/null
+++ b/client/object_patch.go
@@ -0,0 +1,165 @@
+package client
+
+import (
+	"context"
+	"crypto/ecdsa"
+	"errors"
+	"fmt"
+	"io"
+
+	"git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/acl"
+	v2object "git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/object"
+	rpcapi "git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/rpc"
+	"git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/rpc/client"
+	v2session "git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/session"
+	"git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/signature"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/bearer"
+	apistatus "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/client/status"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
+	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
+	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/session"
+)
+
+type ResObjectPatch struct {
+	statusRes
+
+	obj oid.ID
+}
+
+func (r ResObjectPatch) ObjectID() oid.ID {
+	return r.obj
+}
+
+// PrmObjectPatch groups parameters of ObjectPatch operation.
+type PrmObjectPatch struct {
+	XHeaders []string
+
+	BearerToken *bearer.Token
+
+	Session *session.Object
+
+	Local bool
+
+	Address oid.Address
+
+	Key *ecdsa.PrivateKey
+
+	Offset uint64
+
+	Length uint64
+
+	Chunk []byte
+}
+
+func (c *Client) ObjectPatchInit(ctx context.Context, prm PrmObjectPatch) (*objectPatcher, error) {
+	if len(prm.XHeaders)%2 != 0 {
+		return nil, errorInvalidXHeaders
+	}
+
+	var p objectPatcher
+	stream, err := rpcapi.Patch(&c.c, &p.respV2, client.WithContext(ctx))
+	if err != nil {
+		return nil, fmt.Errorf("open stream: %w", err)
+	}
+
+	p.key = &c.prm.Key
+	if prm.Key != nil {
+		p.key = prm.Key
+	}
+	p.client = c
+	p.stream = stream
+	p.addr = prm.Address
+
+	p.req.SetBody(&v2object.PatchRequestBody{})
+
+	meta := new(v2session.RequestMetaHeader)
+	writeXHeadersToMeta(prm.XHeaders, meta)
+
+	if prm.BearerToken != nil {
+		v2BearerToken := new(acl.BearerToken)
+		prm.BearerToken.WriteToV2(v2BearerToken)
+		meta.SetBearerToken(v2BearerToken)
+	}
+
+	if prm.Session != nil {
+		v2SessionToken := new(v2session.Token)
+		prm.Session.WriteToV2(v2SessionToken)
+		meta.SetSessionToken(v2SessionToken)
+	}
+
+	if prm.Local {
+		meta.SetTTL(1)
+	}
+
+	c.prepareRequest(&p.req, meta)
+	return &p, nil
+}
+
+type objectPatcher struct {
+	client *Client
+
+	stream interface {
+		Write(*v2object.PatchRequest) error
+		Close() error
+	}
+
+	key *ecdsa.PrivateKey
+	res ResObjectPatch
+	err error
+
+	addr oid.Address
+
+	req    v2object.PatchRequest
+	respV2 v2object.PatchResponse
+}
+
+func (x *objectPatcher) Patch(_ context.Context, patch *object.Patch) bool {
+	x.req.SetBody(patch.ToV2())
+	x.req.SetVerificationHeader(nil)
+
+	x.err = signature.SignServiceMessage(x.key, &x.req)
+	if x.err != nil {
+		x.err = fmt.Errorf("sign message: %w", x.err)
+		return false
+	}
+
+	x.err = x.stream.Write(&x.req)
+
+	return x.err == nil
+}
+
+func (x *objectPatcher) Close(_ context.Context) (*ResObjectPatch, error) {
+	// Ignore io.EOF error, because it is expected error for client-side
+	// stream termination by the server. E.g. when stream contains invalid
+	// message. Server returns an error in response message (in status).
+	if x.err != nil && !errors.Is(x.err, io.EOF) {
+		return nil, x.err
+	}
+
+	if x.err = x.stream.Close(); x.err != nil {
+		return nil, x.err
+	}
+
+	x.res.st, x.err = x.client.processResponse(&x.respV2)
+	if x.err != nil {
+		return nil, x.err
+	}
+
+	if !apistatus.IsSuccessful(x.res.st) {
+		return &x.res, nil
+	}
+
+	const fieldID = "ID"
+
+	idV2 := x.respV2.Body.ObjectID
+	if idV2 == nil {
+		return nil, newErrMissingResponseField(fieldID)
+	}
+
+	x.err = x.res.obj.ReadFromV2(*idV2)
+	if x.err != nil {
+		x.err = newErrInvalidResponseField(fieldID, x.err)
+	}
+
+	return &x.res, nil
+}