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// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#pragma once
#include "lid_usage_stats.h"
#include <vespa/document/base/globalid.h>
#include <vespa/document/bucket/bucketid.h>
#include <vector>
#include <memory>
namespace search {
/**
* Meta data for a single document.
**/
struct DocumentMetaData {
using DocId = uint32_t;
DocId lid;
uint64_t timestamp;
document::BucketId bucketId;
document::GlobalId gid;
bool removed;
using Vector = std::vector<DocumentMetaData>;
DocumentMetaData() noexcept
: lid(0),
timestamp(0),
bucketId(),
gid(),
removed(false)
{ }
DocumentMetaData(DocId lid_,
uint64_t timestamp_,
document::BucketId bucketId_,
const document::GlobalId &gid_) noexcept
: DocumentMetaData(lid_, timestamp_, bucketId_, gid_, false)
{ }
DocumentMetaData(DocId lid_,
uint64_t timestamp_,
document::BucketId bucketId_,
const document::GlobalId &gid_,
bool removed_) noexcept
: lid(lid_),
timestamp(timestamp_),
bucketId(bucketId_),
gid(gid_),
removed(removed_)
{ }
bool valid() const {
return lid != 0 && timestamp != 0 && bucketId.isSet();
}
};
namespace queryeval { class Blueprint; }
class IGidToLidMapperVisitor;
class BitVector;
/**
* Read interface for a document meta store that provides mapping between
* global document id (gid) and local document id (lid) with additional
* meta data per document.
**/
struct IDocumentMetaStore {
using DocId = uint32_t;
using GlobalId = document::GlobalId;
using BucketId = document::BucketId;
using Timestamp = uint64_t;
virtual ~IDocumentMetaStore() = default;
virtual const BitVector & getValidLids() const = 0;
/**
* Retrieves the gid associated with the given lid.
* Returns true if found, false otherwise.
**/
virtual bool getGid(DocId lid, GlobalId &gid) const = 0;
/**
* Retrieves the gid associated with the given lid, even if the lid has moved.
* Returns true if found, false otherwise.
**/
virtual bool getGidEvenIfMoved(DocId lid, GlobalId &gid) const = 0;
/**
* Retrieves the lid associated with the given gid.
* Returns true if found, false otherwise.
**/
virtual bool getLid(const GlobalId &gid, DocId &lid) const = 0;
/**
* Retrieves the meta data for the document with the given gid.
**/
virtual DocumentMetaData getMetaData(const GlobalId &gid) const = 0;
/**
* Retrieves meta data for all documents contained in the given bucket.
**/
virtual void getMetaData(const BucketId &bucketId, DocumentMetaData::Vector &result) const = 0;
/**
* Returns the lid following the largest lid used in the store.
*
* As long as the reader holds a read guard on the document meta
* store, we guarantee that the meta store info for lids that were
* valid when calling this method will remain valid while the
* guard is held, i.e. lids for newly removed documents are not
* reused while the read guard is held.
*
* Access to lids beyond the returned limit is not safe.
*
* The return value can be used as lid range for queries when
* attribute writer threads are synced, and is propagated as such
* when visibility delay is nonzero and forceCommit() method is
* called regularly on feed views, cf. proton::FastAccessFeedView.
*
* In the future, this method might be renamed to getReaderDocIdLimit().
**/
virtual DocId getCommittedDocIdLimit() const = 0;
/**
* Returns the number of used lids in this store.
*/
virtual DocId getNumUsedLids() const = 0;
/**
* Returns the number of active lids in this store.
* This should be <= getNumUsedLids().
* Active lids correspond to documents in active buckets.
*/
virtual DocId getNumActiveLids() const = 0;
/**
* Returns stats on the usage and availability of lids in this store.
*/
virtual LidUsageStats getLidUsageStats() const = 0;
/**
* Creates a white list blueprint that returns a search iterator
* that gives hits for all documents that should be visible.
**/
virtual std::unique_ptr<queryeval::Blueprint> createWhiteListBlueprint() const = 0;
/**
* Give read access to the current generation of the metastore.
**/
virtual uint64_t getCurrentGeneration() const = 0;
virtual void foreach(const IGidToLidMapperVisitor &visitor) const = 0;
};
}
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