frostfs-sdk-go/client/object_search.go
Evgenii Stratonikov 1bfa9ecdb0 [#48] client: Remove ctx == nil checks
Much less useful after we made context to be passed explicitly.

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
2023-04-13 09:04:09 +03:00

262 lines
7.1 KiB
Go

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"
v2refs "git.frostfs.info/TrueCloudLab/frostfs-api-go/v2/refs"
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"
cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
"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"
)
// PrmObjectSearch groups parameters of ObjectSearch operation.
type PrmObjectSearch struct {
meta v2session.RequestMetaHeader
key *ecdsa.PrivateKey
cnrSet bool
cnrID cid.ID
filters object.SearchFilters
}
// MarkLocal tells the server to execute the operation locally.
func (x *PrmObjectSearch) MarkLocal() {
x.meta.SetTTL(1)
}
// WithinSession specifies session within which the search query must be executed.
//
// Creator of the session acquires the authorship of the request.
// This may affect the execution of an operation (e.g. access control).
//
// Must be signed.
func (x *PrmObjectSearch) WithinSession(t session.Object) {
var tokv2 v2session.Token
t.WriteToV2(&tokv2)
x.meta.SetSessionToken(&tokv2)
}
// WithBearerToken attaches bearer token to be used for the operation.
//
// If set, underlying eACL rules will be used in access control.
//
// Must be signed.
func (x *PrmObjectSearch) WithBearerToken(t bearer.Token) {
var v2token acl.BearerToken
t.WriteToV2(&v2token)
x.meta.SetBearerToken(&v2token)
}
// WithXHeaders specifies list of extended headers (string key-value pairs)
// to be attached to the request. Must have an even length.
//
// Slice must not be mutated until the operation completes.
func (x *PrmObjectSearch) WithXHeaders(hs ...string) {
writeXHeadersToMeta(hs, &x.meta)
}
// UseKey specifies private key to sign the requests.
// If key is not provided, then Client default key is used.
func (x *PrmObjectSearch) UseKey(key ecdsa.PrivateKey) {
x.key = &key
}
// InContainer specifies the container in which to look for objects.
// Required parameter.
func (x *PrmObjectSearch) InContainer(id cid.ID) {
x.cnrID = id
x.cnrSet = true
}
// SetFilters sets filters by which to select objects. All container objects
// match unset/empty filters.
func (x *PrmObjectSearch) SetFilters(filters object.SearchFilters) {
x.filters = filters
}
// ResObjectSearch groups the final result values of ObjectSearch operation.
type ResObjectSearch struct {
statusRes
}
// ObjectListReader is designed to read list of object identifiers from FrostFS system.
//
// Must be initialized using Client.ObjectSearch, any other usage is unsafe.
type ObjectListReader struct {
client *Client
cancelCtxStream context.CancelFunc
err error
res ResObjectSearch
stream interface {
Read(resp *v2object.SearchResponse) error
}
tail []v2refs.ObjectID
}
// Read reads another list of the object identifiers. Works similar to
// io.Reader.Read but copies oid.ID and returns success flag instead of error.
//
// Failure reason can be received via Close.
//
// Panics if buf has zero length.
func (x *ObjectListReader) Read(buf []oid.ID) (int, bool) {
if len(buf) == 0 {
panic("empty buffer in ObjectListReader.ReadList")
}
read := copyIDBuffers(buf, x.tail)
x.tail = x.tail[read:]
if len(buf) == read {
return read, true
}
for {
var resp v2object.SearchResponse
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().GetIDList()
if len(ids) == 0 {
// just skip empty lists since they are not prohibited by protocol
continue
}
ln := copyIDBuffers(buf[read:], ids)
read += ln
if read == len(buf) {
// save the tail
x.tail = append(x.tail, ids[ln:]...)
return read, true
}
}
}
func copyIDBuffers(dst []oid.ID, src []v2refs.ObjectID) int {
var i int
for ; i < len(dst) && i < len(src); i++ {
_ = dst[i].ReadFromV2(src[i])
}
return i
}
// Iterate iterates over the list of found object identifiers.
// f can return true to stop iteration earlier.
//
// Returns an error if object can't be read.
func (x *ObjectListReader) Iterate(f func(oid.ID) bool) error {
buf := make([]oid.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
}
}
}
// Close ends reading list of the matched objects and returns the result of the operation
// along with the final results. Must be called after using the ObjectListReader.
//
// Exactly one return value is non-nil. By default, server status is returned in res structure.
// Any client's internal or transport errors are returned as Go built-in error.
// If Client is tuned to resolve FrostFS API statuses, then FrostFS failures
// codes are returned as error.
//
// Return statuses:
// - global (see Client docs);
// - *apistatus.ContainerNotFound;
// - *apistatus.ObjectAccessDenied;
// - *apistatus.SessionTokenExpired.
func (x *ObjectListReader) Close() (*ResObjectSearch, error) {
defer x.cancelCtxStream()
if x.err != nil && !errors.Is(x.err, io.EOF) {
return nil, x.err
}
return &x.res, nil
}
// ObjectSearchInit initiates object selection through a remote server using FrostFS API protocol.
//
// The call only opens the transmission channel, explicit fetching of matched objects
// is done using the ObjectListReader. Exactly one return value is non-nil.
// Resulting reader must be finally closed.
//
// Returns an error if parameters are set incorrectly (see PrmObjectSearch docs).
// Context is required and must not be nil. It is used for network communication.
func (c *Client) ObjectSearchInit(ctx context.Context, prm PrmObjectSearch) (*ObjectListReader, error) {
// check parameters
if !prm.cnrSet {
return nil, errorMissingContainer
}
var cidV2 v2refs.ContainerID
prm.cnrID.WriteToV2(&cidV2)
var body v2object.SearchRequestBody
body.SetVersion(1)
body.SetContainerID(&cidV2)
body.SetFilters(prm.filters.ToV2())
// init reader
var req v2object.SearchRequest
req.SetBody(&body)
c.prepareRequest(&req, &prm.meta)
key := prm.key
if key == nil {
key = &c.prm.key
}
err := signature.SignServiceMessage(key, &req)
if err != nil {
return nil, fmt.Errorf("sign request: %w", err)
}
var r ObjectListReader
ctx, r.cancelCtxStream = context.WithCancel(ctx)
r.stream, err = rpcapi.SearchObjects(&c.c, &req, client.WithContext(ctx))
if err != nil {
return nil, fmt.Errorf("open stream: %w", err)
}
r.client = c
return &r, nil
}