sgns::crdt::CrdtDatastore¶

Forward declaration of CRDT Set class. More...

#include <crdt_datastore.hpp>

Inherits from std::enable_shared_from_this< CrdtDatastore >

Protected Classes¶

	Name
struct	RootCIDJob
struct	DagWorker

Public Types¶

	Name
enum class	JobStatus
enum class	Error
using base::Buffer	Buffer
using base::Logger	Logger
using storage::rocksdb	RocksDB
using RocksDB::QueryResult	QueryResult
using pb::Delta	Delta
using pb::Element	Element
using ipfs_lite::ipld::IPLDNode	IPLDNode
using CRDTDataFilter::ElementFilterCallback	CRDTElementFilterCallback
using CRDTCallbackManager::NewDataCallback	CRDTNewElementCallback
using CRDTCallbackManager::DeletedDataCallback	CRDTDeletedElementCallback

Public Functions¶

	Name
std::shared_ptr< CrdtDatastore >	New(std::shared_ptr< RocksDB > aDatastore, const HierarchicalKey & aKey, std::shared_ptr< DAGSyncer > aDagSyncer, std::shared_ptr< Broadcaster > aBroadcaster, std::shared_ptr< CrdtOptions > aOptions) Factory method to create a shared_ptr to a CrdtDatastore.
std::shared_ptr< Delta >	DeltaMerge(const std::shared_ptr< Delta > & aDelta1, const std::shared_ptr< Delta > & aDelta2)
std::string	GetValueSuffix()
outcome::result< std::vector< CID > >	DecodeBroadcast(const Buffer & buff)
outcome::result< std::shared_ptr< Delta > >	CreateDeltaToAdd(const std::string & key, const std::string & value)
void	Start() Starts the datastore threads.
virtual	~CrdtDatastore() Destructor of the CRDT datastore.
outcome::result< Buffer >	GetKey(const HierarchicalKey & aKey) const
outcome::result< QueryResult >	QueryKeyValues(std::string_view aPrefix) const
outcome::result< QueryResult >	QueryKeyValues(const std::string & prefix_base, const std::string & middle_part, const std::string & remainder_prefix) const Queries with a middle part that can be a wildcard, negated string or normal string.
std::string	GetKeysPrefix() const
outcome::result< CID >	PutKey(const HierarchicalKey & aKey, const Buffer & aValue, const std::unordered_set< std::string > & topics) Stores the given value in the CRDT store.
outcome::result< bool >	HasKey(const HierarchicalKey & aKey) const
outcome::result< CID >	DeleteKey(const HierarchicalKey & aKey, const std::unordered_set< std::string > & topics)
outcome::result< CID >	Publish(const std::shared_ptr< Delta > & aDelta, const std::unordered_set< std::string > & topics) Publishes a Delta. Creates a DAG node from the given Delta, merges it into the CRDT, and broadcasts the node.
outcome::result< void >	PrintDAG()
outcome::result< std::shared_ptr< Delta > >	CreateDeltaToRemove(const std::string & key) const
void	PrintDataStore()
void	Close()
bool	RegisterElementFilter(const std::string & pattern, CRDTElementFilterCallback filter)
bool	RegisterNewElementCallback(const std::string & pattern, CRDTNewElementCallback callback)
bool	RegisterDeletedElementCallback(const std::string & pattern, CRDTDeletedElementCallback callback)
void	AddTopicName(const std::string & topic) Configure which topic this datastore should filter on.
outcome::result< CrdtHeads::CRDTListResult >	GetHeadList()
outcome::result< void >	RemoveHead(const CID & aCid, const std::string & topic)
outcome::result< uint64_t >	GetHeadHeight(const CID & aCid, const std::string & topic)
outcome::result< void >	AddHead(const CID & aCid, const std::string & topic, uint64_t priority)
outcome::result< JobStatus >	GetJobStatus(const CID & cid)
outcome::result< void >	BroadcastHeadsForTopics(const std::set< std::string > & topics) Broadcast heads for the specified topics.
std::unordered_set< std::string >	GetTopicNames() const

Protected Functions¶

	Name
void	HandleCIDBroadcast() Handles when a CID broadcast gets received If the CID is not known triggers HandleRootCIDBlock.
outcome::result< void >	HandleRootCIDBlock(const CID & aCid) Handles a root CID block by creating a job to fetch and process its content.
outcome::result< RootCIDJob >	CreateRootJob(const CID & aRootCID) Creates a RootCIDJob for the given root CID.
outcome::result< std::set< CID > >	GetLinksToFetch(const RootCIDJob & job) Gets the links to fetch for a given node in a job.
outcome::result< void >	FetchNodes(const RootCIDJob & aRootJob, const std::set< CID > & aLinks) Fetches the nodes for the given links and root job.
outcome::result< Delta >	GetDeltaFromNode(const IPLDNode & aNode, bool created_by_self) Gets the Delta from a given IPLD node, filtering it if it wasn't created by self.
outcome::result< void >	MergeDataFromDelta(const CID & node_cid, const Delta & aDelta) Merges the data from a given Delta into the CRDT set.
outcome::result< void >	ProcessJobIteration(const RootCIDJob & job_to_process) Processes A Root CID job.
outcome::result< void >	Sync(const HierarchicalKey & aKey)
outcome::result< void >	PrintDAGRec(const CID & aCID, uint64_t aDepth, std::vector< CID > & aSet)
void	RebroadcastHeads()
outcome::result< void >	Broadcast(const std::set< CID > & cids, const std::string & topic, boost::optional< libp2p::peer::PeerInfo > peerInfo =boost::none) Broadcasts a set of CIDs. Encodes and broadcasts the provided list of CIDs.
outcome::result< Buffer >	EncodeBroadcast(const std::set< CID > & heads)
outcome::result< std::shared_ptr< IPLDNode > >	CreateIPLDNode(const std::vector< std::pair< CID, std::string > > & aHeads, const std::shared_ptr< Delta > & aDelta, const std::unordered_set< std::string > & topics) const
outcome::result< std::shared_ptr< IPLDNode > >	CreateDAGNode(const std::shared_ptr< Delta > & aDelta, const std::unordered_set< std::string > & topics)
outcome::result< CID >	AddDAGNode(const std::shared_ptr< CrdtDatastore::IPLDNode > & node)
outcome::result< void >	SyncDatastore(const std::vector< HierarchicalKey > & aKeyList)
void	PutElementsCallback(const std::string & key, const Buffer & value, const std::string & cid)
void	DeleteElementsCallback(const std::string & key, const std::string & cid)
void	UpdateCRDTHeads(const CID & rootCID, uint64_t rootPriority, bool add_topics_to_broadcast)
bool	EnqueueRootCID(const CID & cid)
outcome::result< CID >	WaitForJob(const CID & cid)
outcome::result< Buffer >	EncodeBroadcastStatic(const std::set< CID > & heads)

Friends¶

	Name
class	PubSubBroadcasterExt

Detailed Description¶

class sgns::crdt::CrdtDatastore;

Forward declaration of CRDT Set class.

CRDT datastore class based on https://github.com/ipfs/go-ds-crdt

Public Types Documentation¶

enum JobStatus¶

Enumerator	Value	Description
PENDING
COMPLETED
FAILED

enum Error¶

Enumerator	Value	Description
INVALID_PARAM	0
FETCH_ROOT_NODE
NODE_DESERIALIZATION
FETCHING_GRAPH
NODE_CREATION
GET_NODE
INVALID_JOB

using Buffer¶

using sgns::crdt::CrdtDatastore::Buffer = base::Buffer;

using Logger¶

using sgns::crdt::CrdtDatastore::Logger = base::Logger;

using RocksDB¶

using sgns::crdt::CrdtDatastore::RocksDB = storage::rocksdb;

using QueryResult¶

using sgns::crdt::CrdtDatastore::QueryResult = RocksDB::QueryResult;

using Delta¶

using sgns::crdt::CrdtDatastore::Delta = pb::Delta;

using Element¶

using sgns::crdt::CrdtDatastore::Element = pb::Element;

using IPLDNode¶

using sgns::crdt::CrdtDatastore::IPLDNode = ipfs_lite::ipld::IPLDNode;

using CRDTElementFilterCallback¶

using sgns::crdt::CrdtDatastore::CRDTElementFilterCallback = CRDTDataFilter::ElementFilterCallback;

using CRDTNewElementCallback¶

using sgns::crdt::CrdtDatastore::CRDTNewElementCallback = CRDTCallbackManager::NewDataCallback;

using CRDTDeletedElementCallback¶

using sgns::crdt::CrdtDatastore::CRDTDeletedElementCallback = CRDTCallbackManager::DeletedDataCallback;

Public Functions Documentation¶

function New¶

static std::shared_ptr< CrdtDatastore > New(
    std::shared_ptr< RocksDB > aDatastore,
    const HierarchicalKey & aKey,
    std::shared_ptr< DAGSyncer > aDagSyncer,
    std::shared_ptr< Broadcaster > aBroadcaster,
    std::shared_ptr< CrdtOptions > aOptions
)

Factory method to create a shared_ptr to a CrdtDatastore.

Parameters:

aDatastore The underlying database where CRDT is stored
aKey The namespace key on the database where CRDT's variables will be stored
aDagSyncer The MerkleDAG syncer to request content of CIDs
aBroadcaster The broadcaster to publish CIDs
aOptions Options to construct the object

Return: A new instance of CrdtDatastore

function DeltaMerge¶

static std::shared_ptr< Delta > DeltaMerge(
    const std::shared_ptr< Delta > & aDelta1,
    const std::shared_ptr< Delta > & aDelta2
)

Parameters:

aDelta1 Delta to merge
aDelta2 Delta to merge

Return: pointer to merged delta

Static function to merge delta elements and tombstones, use highest priority for the result delta

function GetValueSuffix¶

static std::string GetValueSuffix()

Return: value suffix

Get value suffix used in set, e.g. /v

function DecodeBroadcast¶

static outcome::result< std::vector< CID > > DecodeBroadcast(
    const Buffer & buff
)

Parameters:

buff Buffer data to decode

Return: vector of CIDs or outcome::failure on error

DecodeBroadcast decodes CRDT broadcast data

function CreateDeltaToAdd¶

static outcome::result< std::shared_ptr< Delta > > CreateDeltaToAdd(
    const std::string & key,
    const std::string & value
)

Parameters:

key - delta key to add to datastore
value - delta value to add to datastore

Return: pointer to new delta or outcome::failure on error

Returns a new delta-set adding the given key/value.

function Start¶

void Start()

Starts the datastore threads.

function ~CrdtDatastore¶

virtual ~CrdtDatastore()

Destructor of the CRDT datastore.

function GetKey¶

outcome::result< Buffer > GetKey(
    const HierarchicalKey & aKey
) const

Parameters:

aKey Hierarchical key to get

Return: value as a Buffer

Get the value of an element not tombstoned from the CRDT set by key

function QueryKeyValues¶

outcome::result< QueryResult > QueryKeyValues(
    std::string_view aPrefix
) const

Parameters:

aPrefix prefix to search, if empty string, return all

Return: list of key-value pairs matches prefix

Query CRDT set key-value pairs by prefix, if prefix empty return all elements are not tombstoned

function QueryKeyValues¶

outcome::result< QueryResult > QueryKeyValues(
    const std::string & prefix_base,
    const std::string & middle_part,
    const std::string & remainder_prefix
) const

Queries with a middle part that can be a wildcard, negated string or normal string.

Parameters:

prefix_base The base prefix to query
middle_part Either a string (normal query), '*' or !string
remainder_prefix The remainder part of the query prefix

Return: A list of key value pairs

function GetKeysPrefix¶

std::string GetKeysPrefix() const

Return: key prefix

Get key prefix used in set, e.g. /namespace/s/k/

function PutKey¶

outcome::result< CID > PutKey(
    const HierarchicalKey & aKey,
    const Buffer & aValue,
    const std::unordered_set< std::string > & topics
)

Stores the given value in the CRDT store.

Parameters:

aKey Hierarchical key to put
aValue Value to be stored
topics Topics to publish to

Return: outcome::success if stored and broadcasted successfully, or outcome::failure otherwise.

function HasKey¶

outcome::result< bool > HasKey(
    const HierarchicalKey & aKey
) const

Parameters:

aKey HierarchicalKey to look for in set

Return: true if key found or false if not found or outcome::failure on error

HasKey returns whether the key is mapped to a value in set

function DeleteKey¶

outcome::result< CID > DeleteKey(
    const HierarchicalKey & aKey,
    const std::unordered_set< std::string > & topics
)

Parameters:

aKey HierarchicalKey to delete from set
topics Topics to publish to

Return: outcome::failure on error or success otherwise

Delete removes the value for given key.

function Publish¶

outcome::result< CID > Publish(
    const std::shared_ptr< Delta > & aDelta,
    const std::unordered_set< std::string > & topics
)

Publishes a Delta. Creates a DAG node from the given Delta, merges it into the CRDT, and broadcasts the node.

Parameters:

aDelta Delta to publish
topics Topics to publish to

Return: returns outcome::success on success or outcome::failure otherwise

function PrintDAG¶

outcome::result< void > PrintDAG()

Return: returns outcome::success on success or outcome::failure otherwise

PrintDAG pretty prints the current Merkle-DAG using the given printFunc

function CreateDeltaToRemove¶

outcome::result< std::shared_ptr< Delta > > CreateDeltaToRemove(
    const std::string & key
) const

Parameters:

key - delta key to remove from datastore

Return: pointer to delta or outcome::failure on error

Returns a new delta-set removing the given keys with prefix /namespace/s/key

function PrintDataStore¶

void PrintDataStore()

function Close¶

void Close()

Close shuts down the CRDT datastore and worker threads. It should not be used afterwards.

function RegisterElementFilter¶

bool RegisterElementFilter(
    const std::string & pattern,
    CRDTElementFilterCallback filter
)

function RegisterNewElementCallback¶

bool RegisterNewElementCallback(
    const std::string & pattern,
    CRDTNewElementCallback callback
)

function RegisterDeletedElementCallback¶

bool RegisterDeletedElementCallback(
    const std::string & pattern,
    CRDTDeletedElementCallback callback
)

function AddTopicName¶

void AddTopicName(
    const std::string & topic
)

Configure which topic this datastore should filter on.

Parameters:

topic The topic name to use when filtering links. Only links whose IPLDLinkImpl::getName() equals this string will be processed.

When processing or rebroadcasting Merkle-DAG links, only those whose name exactly matches the topic set via this call will be considered.

function GetHeadList¶

outcome::result< CrdtHeads::CRDTListResult > GetHeadList()

function RemoveHead¶

outcome::result< void > RemoveHead(
    const CID & aCid,
    const std::string & topic
)

function GetHeadHeight¶

outcome::result< uint64_t > GetHeadHeight(
    const CID & aCid,
    const std::string & topic
)

function AddHead¶

outcome::result< void > AddHead(
    const CID & aCid,
    const std::string & topic,
    uint64_t priority
)

function GetJobStatus¶

outcome::result< JobStatus > GetJobStatus(
    const CID & cid
)

function BroadcastHeadsForTopics¶

outcome::result< void > BroadcastHeadsForTopics(
    const std::set< std::string > & topics
)

Broadcast heads for the specified topics.

Parameters:

topics Vector of topic names to broadcast heads for

Return: outcome::success on success, or outcome::failure on error

function GetTopicNames¶

std::unordered_set< std::string > GetTopicNames() const

Protected Functions Documentation¶

function HandleCIDBroadcast¶

void HandleCIDBroadcast()

Handles when a CID broadcast gets received If the CID is not known triggers HandleRootCIDBlock.

function HandleRootCIDBlock¶

outcome::result< void > HandleRootCIDBlock(
    const CID & aCid
)

Handles a root CID block by creating a job to fetch and process its content.

Parameters:

aCid The root CID to be handled

Return: Success if the Root Job was created, or failure otherwise

function CreateRootJob¶

outcome::result< RootCIDJob > CreateRootJob(
    const CID & aRootCID
)

Creates a RootCIDJob for the given root CID.

Parameters:

aRootCID The root CID to create the job for

Return: Success if Root Job created, or failure otherwise

function GetLinksToFetch¶

outcome::result< std::set< CID > > GetLinksToFetch(
    const RootCIDJob & job
)

Gets the links to fetch for a given node in a job.

Parameters:

job The root job of the current links to fetch

Return: List of CIDs to fetch, or failure otherwise

function FetchNodes¶

outcome::result< void > FetchNodes(
    const RootCIDJob & aRootJob,
    const std::set< CID > & aLinks
)

Fetches the nodes for the given links and root job.

Parameters:

aRootJob The root job of the current links to fetch
aLinks The links to fetch

Return: Success if the nodes were fetched, or failure otherwise

function GetDeltaFromNode¶

outcome::result< Delta > GetDeltaFromNode(
    const IPLDNode & aNode,
    bool created_by_self
)

Gets the Delta from a given IPLD node, filtering it if it wasn't created by self.

Parameters:

aNode The IPLD node to get the Delta from
created_by_self True if the node was created by self, false otherwise

Return: The Delta contained in the node, or failure otherwise

function MergeDataFromDelta¶

outcome::result< void > MergeDataFromDelta(
    const CID & node_cid,
    const Delta & aDelta
)

Merges the data from a given Delta into the CRDT set.

Parameters:

node_cid The CID of the node from which the Delta was obtained
aDelta The Delta to be merged

Return: Success if the Delta was merged, or failure otherwise

function ProcessJobIteration¶

outcome::result< void > ProcessJobIteration(
    const RootCIDJob & job_to_process
)

Processes A Root CID job.

Parameters:

job_to_process The job received by either HandleCIDBroadcast or by AddDAGNode

Return: Success if the job was processed, or failure otherwise

function Sync¶

outcome::result< void > Sync(
    const HierarchicalKey & aKey
)

Return: returns outcome::success on success or outcome::failure otherwise

Sync ensures that all the data under the given prefix is flushed to disk in the underlying datastore

function PrintDAGRec¶

outcome::result< void > PrintDAGRec(
    const CID & aCID,
    uint64_t aDepth,
    std::vector< CID > & aSet
)

Parameters:

aCID CID of DAG record
aDepth depth used for indenting printed records
aSet set of CIDs to print

Return: returns outcome::success on success or outcome::failure otherwise

Helper funtion to print Merkle-DAG records

function RebroadcastHeads¶

void RebroadcastHeads()

Regularly send out a list of heads that we have not recently seen

function Broadcast¶

outcome::result< void > Broadcast(
    const std::set< CID > & cids,
    const std::string & topic,
    boost::optional< libp2p::peer::PeerInfo > peerInfo =boost::none
)

Broadcasts a set of CIDs. Encodes and broadcasts the provided list of CIDs.

Parameters:

cids The list of CIDs to broadcast.
topic The topic to broadcast to.
peerInfo Optional peer info to avoid repeated GetPeerInfo calls.

Return: outcome::success on success, or outcome::failure if an error occurs.

function EncodeBroadcast¶

outcome::result< Buffer > EncodeBroadcast(
    const std::set< CID > & heads
)

Parameters:

heads list of CIDs

Return: data encoded into Buffer data or outcome::failure on error

EncodeBroadcast encodes list of CIDs to CRDT broadcast data

function CreateIPLDNode¶

outcome::result< std::shared_ptr< IPLDNode > > CreateIPLDNode(
    const std::vector< std::pair< CID, std::string > > & aHeads,
    const std::shared_ptr< Delta > & aDelta,
    const std::unordered_set< std::string > & topics
) const

Parameters:

aHeads list of CIDs to add to node as IPLD links
aDelta Delta to serialize into IPLD node
topics Topics to add as links

Return: IPLD node or outcome::failure on error

CreateIPLDNode add block node to DAGSyncer

function CreateDAGNode¶

outcome::result< std::shared_ptr< IPLDNode > > CreateDAGNode(
    const std::shared_ptr< Delta > & aDelta,
    const std::unordered_set< std::string > & topics
)

function AddDAGNode¶

outcome::result< CID > AddDAGNode(
    const std::shared_ptr< CrdtDatastore::IPLDNode > & node
)

Parameters:

node Node to add and process

Return: CID or outcome::failure on error

AddDAGNode adds node to DAGSyncer and processes new blocks.

function SyncDatastore¶

outcome::result< void > SyncDatastore(
    const std::vector< HierarchicalKey > & aKeyList
)

Parameters:

aKeyList all heads and the set entries related to the given prefix

Return: returns outcome::success on success or outcome::failure otherwise

SyncDatastore sync heads and set datastore

function PutElementsCallback¶

void PutElementsCallback(
    const std::string & key,
    const Buffer & value,
    const std::string & cid
)

function DeleteElementsCallback¶

void DeleteElementsCallback(
    const std::string & key,
    const std::string & cid
)

function UpdateCRDTHeads¶

void UpdateCRDTHeads(
    const CID & rootCID,
    uint64_t rootPriority,
    bool add_topics_to_broadcast
)

function EnqueueRootCID¶

bool EnqueueRootCID(
    const CID & cid
)

function WaitForJob¶

outcome::result< CID > WaitForJob(
    const CID & cid
)

function EncodeBroadcastStatic¶

static outcome::result< Buffer > EncodeBroadcastStatic(
    const std::set< CID > & heads
)

Parameters:

heads list of CIDs

Return: data encoded into Buffer data or outcome::failure on error

EncodeBroadcastStatic encodes list of CIDs to CRDT broadcast data

Friends¶

friend PubSubBroadcasterExt¶

friend class PubSubBroadcasterExt(
    PubSubBroadcasterExt 
);

Updated on 2026-03-04 at 13:10:43 -0800