knowrob::QueryableStorage Class Reference

#include <QueryableStorage.h>

Inheritance diagram for knowrob::QueryableStorage:

Collaboration diagram for knowrob::QueryableStorage:

Public Member Functions
	QueryableStorage (StorageFeatures features=StorageFeature::NothingSpecial)
	~QueryableStorage () override=default
virtual bool	isPersistent () const =0
virtual void	foreach (const TripleVisitor &visitor) const
virtual void	batch (const TripleHandler &callback) const =0
virtual void	batchOrigin (std::string_view origin, const TripleHandler &callback)=0
virtual bool	contains (const Triple &triple)
virtual void	match (const TriplePattern &query, const TripleVisitor &visitor)
virtual void	query (const GraphQueryPtr &query, const BindingsHandler &callback)=0
virtual void	count (const ResourceCounter &callback) const =0
std::vector< VersionedOriginPtr >	getOrigins ()
std::optional< std::string >	getVersionOfOrigin (std::string_view origin)
void	setVersionOfOrigin (std::string_view origin, std::string_view version)
void	dropSessionOrigins ()
GraphQueryExpansionPtr	expand (const GraphQueryPtr &q)
	QueryableStorage (StorageFeatures features=StorageFeature::NothingSpecial)
	~QueryableStorage () override=default
virtual bool	isPersistent () const =0
virtual void	foreach (const TripleVisitor &visitor) const
virtual void	batch (const TripleHandler &callback) const =0
virtual void	batchOrigin (std::string_view origin, const TripleHandler &callback)=0
virtual bool	contains (const Triple &triple)
virtual void	match (const TriplePattern &query, const TripleVisitor &visitor)
virtual void	query (const GraphQueryPtr &query, const BindingsHandler &callback)=0
virtual void	count (const ResourceCounter &callback) const =0
std::vector< VersionedOriginPtr >	getOrigins ()
std::optional< std::string >	getVersionOfOrigin (std::string_view origin)
void	setVersionOfOrigin (std::string_view origin, std::string_view version)
void	dropSessionOrigins ()
GraphQueryExpansionPtr	expand (const GraphQueryPtr &q)
Public Member Functions inherited from knowrob::Storage
	Storage (StorageFeatures features=StorageFeature::NothingSpecial)
virtual	~Storage ()=default
PluginLanguage	storageLanguage () const
const auto &	vocabulary () const
void	setVocabulary (std::shared_ptr< Vocabulary > vocabulary)
bool	supports (StorageFeature feature) const
virtual bool	insertOne (const Triple &triple)=0
virtual bool	insertAll (const TripleContainerPtr &triples)=0
virtual bool	removeOne (const Triple &triple)=0
virtual bool	removeAll (const TripleContainerPtr &triples)=0
virtual bool	removeAllWithOrigin (std::string_view origin)=0
virtual bool	initializeBackend (const PropertyTree &config)=0
std::optional< std::string >	getVersionOfOrigin (std::string_view origin) const
void	setVersionOfOrigin (std::string_view origin, std::optional< std::string_view > version)
	Storage (StorageFeatures features=StorageFeature::NothingSpecial)
virtual	~Storage ()=default
PluginLanguage	storageLanguage () const
const auto &	vocabulary () const
void	setVocabulary (std::shared_ptr< Vocabulary > vocabulary)
bool	supports (StorageFeature feature) const
virtual bool	insertOne (const Triple &triple)=0
virtual bool	insertAll (const TripleContainerPtr &triples)=0
virtual bool	removeOne (const Triple &triple)=0
virtual bool	removeAll (const TripleContainerPtr &triples)=0
virtual bool	removeAllWithOrigin (std::string_view origin)=0
virtual bool	initializeBackend (const PropertyTree &config)=0
std::optional< std::string >	getVersionOfOrigin (std::string_view origin) const
void	setVersionOfOrigin (std::string_view origin, std::optional< std::string_view > version)
Public Member Functions inherited from knowrob::DataSourceHandler
	DataSourceHandler ()=default
virtual	~DataSourceHandler ()=default
void	addDataHandler (const std::string &format, const DataSourceLoader &fn)
bool	loadDataSource (const DataSourcePtr &dataSource)
bool	hasDataHandler (const DataSourcePtr &dataSource) const
	DataSourceHandler ()=default
virtual	~DataSourceHandler ()=default
void	addDataHandler (const std::string &format, const DataSourceLoader &fn)
bool	loadDataSource (const DataSourcePtr &dataSource)
bool	hasDataHandler (const DataSourcePtr &dataSource) const

Static Public Member Functions
static std::shared_ptr< AnswerYes >	yes (const GraphPathQueryPtr &original, const GraphQueryExpansionPtr &expansion, const BindingsPtr &bindings)
static std::shared_ptr< AnswerNo >	no (const GraphPathQueryPtr &q)
static std::shared_ptr< AnswerYes >	yes (const GraphPathQueryPtr &original, const GraphQueryExpansionPtr &expansion, const BindingsPtr &bindings)
static std::shared_ptr< AnswerNo >	no (const GraphPathQueryPtr &q)

Static Public Attributes
static AtomPtr	versionProperty = IRIAtom::Tabled("http://knowrob.org/kb/knowrob.owl#hasVersionOfOrigin")

Additional Inherited Members
Protected Member Functions inherited from knowrob::Storage
void	enableFeature (StorageFeature feature)
void	setStorageLanguage (PluginLanguage storageLanguage)
void	enableFeature (StorageFeature feature)
void	setStorageLanguage (PluginLanguage storageLanguage)
Protected Member Functions inherited from knowrob::DataSourceHandler
virtual bool	loadDataSourceWithUnknownFormat (const DataSourcePtr &)
virtual bool	loadDataSourceWithUnknownFormat (const DataSourcePtr &)
Protected Attributes inherited from knowrob::Storage
std::map< std::string, std::string >	originVersions_
std::shared_ptr< Vocabulary >	vocabulary_
StorageFeatures	features_
PluginLanguage	storageLanguage_
Protected Attributes inherited from knowrob::DataSourceHandler
std::map< std::string, DataSourceLoader >	dataSourceHandler_

Detailed Description

A backend that can be queried.

Definition at line 25 of file QueryableStorage.h.

Constructor & Destructor Documentation

QueryableStorage() [1/2]

QueryableStorage::QueryableStorage ( StorageFeatures  features = StorageFeature::NothingSpecial )

explicit

Definition at line 20 of file QueryableStorage.cpp.

        : Storage(features) {
}

~QueryableStorage() [1/2]

knowrob::QueryableStorage::~QueryableStorage ( )

overridedefault

QueryableStorage() [2/2]

knowrob::QueryableStorage::QueryableStorage ( StorageFeatures  features = StorageFeature::NothingSpecial )

explicit

~QueryableStorage() [2/2]

knowrob::QueryableStorage::~QueryableStorage ( )

overridedefault

Member Function Documentation

batch() [1/2]

virtual void knowrob::QueryableStorage::batch ( const TripleHandler &  callback ) const

pure virtual

Iterate over all triples in the model.

Parameters

callback

the callback to handle the triples.

Returns

true if the iteration was successful.

Implemented in knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, knowrob::PrologBackend, knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, and knowrob::PrologBackend.

batch() [2/2]

virtual void knowrob::QueryableStorage::batch ( const TripleHandler &  callback ) const

pure virtual

Iterate over all triples in the model.

Parameters

callback

the callback to handle the triples.

Returns

true if the iteration was successful.

Implemented in knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, knowrob::PrologBackend, knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, and knowrob::PrologBackend.

batchOrigin() [1/2]

virtual void knowrob::QueryableStorage::batchOrigin ( std::string_view  origin, const TripleHandler &  callback  )

pure virtual

Iterate over all triples in the model that have a given origin.

Parameters

origin	the origin of the triples.
callback	the callback to handle the triples.

Returns

true if the iteration was successful.

Implemented in knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, knowrob::PrologBackend, knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, and knowrob::PrologBackend.

batchOrigin() [2/2]

virtual void knowrob::QueryableStorage::batchOrigin ( std::string_view  origin, const TripleHandler &  callback  )

pure virtual

Iterate over all triples in the model that have a given origin.

Parameters

origin	the origin of the triples.
callback	the callback to handle the triples.

Returns

true if the iteration was successful.

Implemented in knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, knowrob::PrologBackend, knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, and knowrob::PrologBackend.

contains() [1/2]

bool QueryableStorage::contains ( const Triple &  triple )

virtual

Parameters

triple

a framed triple.

Returns

true if the model contains the triple.

Reimplemented in knowrob::RedlandModel, and knowrob::RedlandModel.

Definition at line 83 of file QueryableStorage.cpp.

                                                    {
    bool hasTriple = false;
    match(TriplePattern(triple), [&hasTriple](const TriplePtr &) {
        hasTriple = true;
    });
    return hasTriple;
}

contains() [2/2]

virtual bool knowrob::QueryableStorage::contains ( const Triple &  triple )

virtual

Parameters

triple

a framed triple.

Returns

true if the model contains the triple.

Reimplemented in knowrob::RedlandModel, and knowrob::RedlandModel.

count() [1/2]

virtual void knowrob::QueryableStorage::count ( const ResourceCounter &  callback ) const

pure virtual

Parameters

callback

a function that is called for each resource and its count.

Implemented in knowrob::SPARQLBackend, knowrob::MongoKnowledgeGraph, knowrob::PrologBackend, knowrob::SPARQLBackend, knowrob::MongoKnowledgeGraph, and knowrob::PrologBackend.

count() [2/2]

virtual void knowrob::QueryableStorage::count ( const ResourceCounter &  callback ) const

pure virtual

Parameters

callback

a function that is called for each resource and its count.

Implemented in knowrob::SPARQLBackend, knowrob::MongoKnowledgeGraph, knowrob::PrologBackend, knowrob::SPARQLBackend, knowrob::MongoKnowledgeGraph, and knowrob::PrologBackend.

dropSessionOrigins() [1/2]

void QueryableStorage::dropSessionOrigins

(

)

Delete triples that have been asserted from a "session" origin.

Definition at line 52 of file QueryableStorage.cpp.

                                          {
    removeAllWithOrigin(ImportHierarchy::ORIGIN_USER);
    removeAllWithOrigin(ImportHierarchy::ORIGIN_REASONER);
    removeAllWithOrigin(ImportHierarchy::ORIGIN_SESSION);
}

dropSessionOrigins() [2/2]

void knowrob::QueryableStorage::dropSessionOrigins

(

)

Delete triples that have been asserted from a "session" origin.

expand() [1/2]

GraphQueryExpansionPtr QueryableStorage::expand

(

const GraphQueryPtr &

q

)

Compute the expansion of a graph path query.

Parameters

q	a graph path query.

Returns

the expansion of the query.

Definition at line 362 of file QueryableStorage.cpp.

                                                                      {
    // Expand the query. Currently, this is mainly used to compute the answer frame here.
    // But also to insert some builtins for occasional triples.
    auto exp_ctx = std::make_shared<GraphQueryExpansion>();
    exp_ctx->query_ctx = q->ctx();
    exp_ctx->with_reassignment = supports(StorageFeature::ReAssignment);
    exp_ctx->expanded = expand_query(q, *exp_ctx);
    return exp_ctx;
}

expand() [2/2]

GraphQueryExpansionPtr knowrob::QueryableStorage::expand

(

const GraphQueryPtr &

q

)

Compute the expansion of a graph path query.

Parameters

q	a graph path query.

Returns

the expansion of the query.

foreach() [1/2]

void QueryableStorage::foreach ( const TripleVisitor &  visitor ) const

virtual

Iterate over all triples in the model.

Parameters

visitor

the callback to handle the triples.

Returns

true if the iteration was successful.

Reimplemented in knowrob::MongoKnowledgeGraph, and knowrob::MongoKnowledgeGraph.

Definition at line 91 of file QueryableStorage.cpp.

                                                                 {
    batch([&](const TripleContainerPtr &container) {
        for (auto &triple: *container) {
            visitor(triple);
        }
    });
}

foreach() [2/2]

virtual void knowrob::QueryableStorage::foreach ( const TripleVisitor &  visitor ) const

virtual

Iterate over all triples in the model.

Parameters

visitor

the callback to handle the triples.

Returns

true if the iteration was successful.

Reimplemented in knowrob::MongoKnowledgeGraph, and knowrob::MongoKnowledgeGraph.

getOrigins() [1/2]

std::vector< VersionedOriginPtr > QueryableStorage::getOrigins

(

)

Returns

a list of all origins that have been asserted.

Definition at line 24 of file QueryableStorage.cpp.

                                                           {
    static auto v_origin = std::make_shared<Variable>("Origin");
    static auto v_version = std::make_shared<Variable>("Version");
    std::vector<VersionedOriginPtr> origins;
    match(TriplePattern(v_origin, versionProperty, v_version),
          [&](const TriplePtr &triple) {
              origins.push_back(std::make_shared<VersionedOrigin>(triple->subject(), triple->valueAsString()));
          });
    return origins;
}

getOrigins() [2/2]

std::vector<VersionedOriginPtr> knowrob::QueryableStorage::getOrigins

(

)

Returns

a list of all origins that have been asserted.

getVersionOfOrigin() [1/2]

std::optional< std::string > QueryableStorage::getVersionOfOrigin

(

std::string_view

origin

)

Parameters

origin

an origin string.

Returns

the version of the origin, or an empty optional if the origin is unknown.

Definition at line 44 of file QueryableStorage.cpp.

                                                                                 {
    static auto v_version = std::make_shared<Variable>("Version");
    std::optional<std::string> version;
    match(TriplePattern(std::make_shared<Atom>(origin), versionProperty, v_version),
          [&](const TriplePtr &triple) { version = triple->createStringValue(); });
    return version;
}

getVersionOfOrigin() [2/2]

std::optional<std::string> knowrob::QueryableStorage::getVersionOfOrigin

(

std::string_view

origin

)

Parameters

origin

an origin string.

Returns

the version of the origin, or an empty optional if the origin is unknown.

isPersistent() [1/2]

virtual bool knowrob::QueryableStorage::isPersistent ( ) const

pure virtual

Returns

true if the backend is persistent.

Implemented in knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, knowrob::PrologBackend, knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, and knowrob::PrologBackend.

isPersistent() [2/2]

virtual bool knowrob::QueryableStorage::isPersistent ( ) const

pure virtual

Returns

true if the backend is persistent.

Implemented in knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, knowrob::PrologBackend, knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, and knowrob::PrologBackend.

match() [1/2]

void QueryableStorage::match ( const TriplePattern &  query, const TripleVisitor &  visitor  )

virtual

Parameters

query	a framed triple pattern.
visitor	a function that is called for each matching framed triple.

Reimplemented in knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, knowrob::RedlandModel, and knowrob::MongoKnowledgeGraph.

Definition at line 68 of file QueryableStorage.cpp.

                                                                                 {
    auto graph_query = std::make_shared<GraphQuery>(
            std::make_shared<GraphPattern>(std::make_shared<TriplePattern>(q)),
            DefaultQueryContext());
    query(graph_query, [&](const BindingsPtr &bindings) {
        TriplePtr triplePtr;
        // create a triple view that holds a reference to the bindings.
        // this is done to allow the visitor to take over the ownership of the triple.
        triplePtr.ptr = new TripleView_withBindings(bindings);
        triplePtr.owned = true;
        q.instantiateInto(*triplePtr, bindings);
        visitor(triplePtr);
    });
}

match() [2/2]

virtual void knowrob::QueryableStorage::match ( const TriplePattern &  query, const TripleVisitor &  visitor  )

virtual

Parameters

query	a framed triple pattern.
visitor	a function that is called for each matching framed triple.

Reimplemented in knowrob::RedlandModel, knowrob::MongoKnowledgeGraph, knowrob::RedlandModel, and knowrob::MongoKnowledgeGraph.

no() [1/2]

std::shared_ptr< AnswerNo > QueryableStorage::no ( const GraphPathQueryPtr &  q )

static

Generates a negative answer to a query.

Parameters

q	a graph path query.

Returns

a negative answer to the query.

Definition at line 137 of file QueryableStorage.cpp.

                                                                       {
    static const auto edbTerm = Atom::Tabled("EDB");
 
    // send one negative answer if no positive answer was found
    auto negativeAnswer = std::make_shared<AnswerNo>();
    negativeAnswer->setReasonerTerm(edbTerm);
    // Apply query context "origin" and "perspective" to the answer if any
    negativeAnswer->applyFrame(q->ctx()->selector);
    // the answer is uncertain as we only were not able to obtain a positive answer
    // which does not mean that there is no positive answer.
    negativeAnswer->setIsUncertain(true, std::nullopt);
 
    // Add ungrounded literals to negative answer.
    // But at the moment the information is not provided by EDBs, would be difficult to implement e.g. in MongoDB.
    // Well at least we know if the query is only a single triple pattern.
    if (q->path().size() == 1) {
        negativeAnswer->addUngrounded(q->path().front()->predicate(),
                                      q->path().front()->isNegated());
    }
    return negativeAnswer;
}

no() [2/2]

static std::shared_ptr<AnswerNo> knowrob::QueryableStorage::no ( const GraphPathQueryPtr &  q )

static

Generates a negative answer to a query.

Parameters

q	a graph path query.

Returns

a negative answer to the query.

query() [1/2]

virtual void knowrob::QueryableStorage::query ( const GraphQueryPtr &  query, const BindingsHandler &  callback  )

pure virtual

Submits a graph query to this storage.

Parameters

query	a graph query
callback	a function that is called for each answer to the query.

Implemented in knowrob::SPARQLBackend, knowrob::MongoKnowledgeGraph, knowrob::PrologBackend, knowrob::SPARQLBackend, knowrob::MongoKnowledgeGraph, and knowrob::PrologBackend.

query() [2/2]

virtual void knowrob::QueryableStorage::query ( const GraphQueryPtr &  query, const BindingsHandler &  callback  )

pure virtual

Submits a graph query to this storage.

Parameters

query	a graph query
callback	a function that is called for each answer to the query.

Implemented in knowrob::SPARQLBackend, knowrob::MongoKnowledgeGraph, knowrob::PrologBackend, knowrob::SPARQLBackend, knowrob::MongoKnowledgeGraph, and knowrob::PrologBackend.

setVersionOfOrigin() [1/2]

void QueryableStorage::setVersionOfOrigin	(	std::string_view	origin,
		std::string_view	version
	)

Set the version of an origin.

Parameters

origin	an origin string.
version	a version string.

Definition at line 35 of file QueryableStorage.cpp.

                                                                                       {
    TripleView triple;
    triple.setSubject(origin);
    triple.setPredicate(versionProperty->stringForm());
    triple.setStringValue(version);
    triple.setGraph(origin);
    insertOne(triple);
}

setVersionOfOrigin() [2/2]

void knowrob::QueryableStorage::setVersionOfOrigin	(	std::string_view	origin,
		std::string_view	version
	)

Set the version of an origin.

Parameters

origin	an origin string.
version	a version string.

yes() [1/2]

std::shared_ptr< AnswerYes > QueryableStorage::yes ( const GraphPathQueryPtr &  original, const GraphQueryExpansionPtr &  expansion, const BindingsPtr &  bindings  )

static

Generates a positive answer to a query.

Parameters

original	a graph path query.
expansion	a graph query expansion.
bindings	a set of bindings.

Returns

a positive answer to the query.

Definition at line 99 of file QueryableStorage.cpp.

                                                                              {
    static const auto edbTerm = Atom::Tabled("EDB");
 
    auto positiveAnswer = std::make_shared<AnswerYes>(bindings);
    // Indicate that EDB has computed the grounding.
    positiveAnswer->setReasonerTerm(edbTerm);
    // Apply query context to the answer for some parameters.
    positiveAnswer->applyFrame(original->ctx()->selector);
 
    // Add predicate groundings to the answer
    for (auto &rdfLiteral: original->path()) {
        auto p = rdfLiteral->predicate();
        auto p_instance = applyBindings(p, *positiveAnswer->substitution());
        positiveAnswer->addGrounding(
                std::static_pointer_cast<Predicate>(p_instance),
                rdfLiteral->isNegated(),
                positiveAnswer->frame());
    }
 
    // The answer is uncertain if any of the groundings is uncertain.
    positiveAnswer->setIsUncertain(
            std::any_of(expanded->u_vars.begin(), expanded->u_vars.end(), [&](const VariablePtr &v) {
                auto &u_v = bindings->get(v->name());
                return (u_v && u_v->isNumeric() && std::static_pointer_cast<Numeric>(u_v)->asBoolean());
            }), std::nullopt);
 
    // The answer is occasional if any of the groundings has occasional=true flag
    positiveAnswer->setIsOccasionallyTrue(
            std::any_of(expanded->o_vars.begin(), expanded->o_vars.end(), [&](const VariablePtr &v) {
                auto &o_v = bindings->get(v->name());
                return (o_v && o_v->isNumeric() && std::static_pointer_cast<Numeric>(o_v)->asBoolean());
            }));
 
    return positiveAnswer;
}

yes() [2/2]

static std::shared_ptr<AnswerYes> knowrob::QueryableStorage::yes ( const GraphPathQueryPtr &  original, const GraphQueryExpansionPtr &  expansion, const BindingsPtr &  bindings  )

static

Generates a positive answer to a query.

Parameters

original	a graph path query.
expansion	a graph query expansion.
bindings	a set of bindings.

Returns

a positive answer to the query.

Member Data Documentation

versionProperty

AtomPtr QueryableStorage::versionProperty = IRIAtom::Tabled("http://knowrob.org/kb/knowrob.owl#hasVersionOfOrigin")

static

Definition at line 27 of file QueryableStorage.h.

---

The documentation for this class was generated from the following files:

• build/_CPack_Packages/Linux/DEB/knowrob-2.1.0-Linux/usr/include/knowrob/storage/QueryableStorage.h
• src/storage/QueryableStorage.cpp