knowrob::DataSource Class Reference

#include <DataSource.h>

Inheritance diagram for knowrob::DataSource:

Collaboration diagram for knowrob::DataSource:

Public Member Functions
	DataSource (URI uri, std::string_view format, DataSourceType dataSourceType)
const auto &	uri () const
const auto &	path () const
const auto &	format () const
DataSourceType	dataSourceType () const
auto	name () const
auto	version () const
	DataSource (URI uri, std::string_view format, DataSourceType dataSourceType)
const auto &	uri () const
const auto &	path () const
const auto &	format () const
DataSourceType	dataSourceType () const
auto	name () const
auto	version () const

Static Public Member Functions
static std::string	getNameFromURI (const std::string &uriString)
static std::string	getVersionFromURI (const std::string &uriString)
static bool	isVersionString (const std::string &versionString)
static std::shared_ptr< DataSource >	create (const VocabularyPtr &vocabulary, const boost::property_tree::ptree &config)
static std::string	getNameFromURI (const std::string &uriString)
static std::string	getVersionFromURI (const std::string &uriString)
static bool	isVersionString (const std::string &versionString)
static std::shared_ptr< DataSource >	create (const VocabularyPtr &vocabulary, const boost::property_tree::ptree &config)

Protected Attributes
DataSourceType	dataSourceType_
std::string	format_
URI	uri_

Detailed Description

A data source is a source of data that can be loaded into a subsystem of the knowledge base. This can be a file, a database, a web service, etc.

Definition at line 26 of file DataSource.h.

Constructor & Destructor Documentation

DataSource() [1/2]

DataSource::DataSource	(	URI	uri,
		std::string_view	format,
		DataSourceType	dataSourceType
	)

Create a data source.

Parameters

uri	URI of the data source.
format	string identifier of the data format.
dataSourceType	the type of the data source.

Definition at line 30 of file DataSource.cpp.

        : dataSourceType_(dataSourceType),
          format_(format),
          uri_(std::move(uri)) {
}

DataSource() [2/2]

knowrob::DataSource::DataSource	(	URI	uri,
		std::string_view	format,
		DataSourceType	dataSourceType
	)

Create a data source.

Parameters

uri	URI of the data source.
format	string identifier of the data format.
dataSourceType	the type of the data source.

Member Function Documentation

create() [1/2]

DataSourcePtr DataSource::create ( const VocabularyPtr &  vocabulary, const boost::property_tree::ptree &  config  )

static

Create a data source from a configuration.

Parameters

vocabulary	the vocabulary of the knowledge base.
config	a property tree used to configure this.

Returns

a data source

Definition at line 105 of file DataSource.cpp.

                                                                                                       {
    static const std::string formatDefault = {};
 
    // read data source settings
    URI dataSourceURI(config);
    auto dataSourceFormat = config.get(DATA_SOURCE_SETTING_FORMAT, formatDefault);
    auto o_dataSourceLanguage = config.get_optional<std::string>(DATA_SOURCE_SETTING_LANG);
    auto o_type = config.get_optional<std::string>(DATA_SOURCE_SETTING_TYPE);
    auto isOntology = isOntologySourceType(dataSourceFormat, o_dataSourceLanguage, o_type);
    // an optional frame can be applied to all triples in a data source
    auto o_tripleFrame = config.get_child_optional(DATA_SOURCE_SETTING_FRAME);
    std::shared_ptr<GraphSelector> tripleFrame;
    if (o_tripleFrame) {
        tripleFrame = std::make_shared<GraphSelector>();
        tripleFrame->set(*o_tripleFrame);
    }
 
    if (isOntology && o_type && o_type.value() == DATA_SOURCE_TYPE_SPARQL) {
        auto sparqlService = std::make_shared<SPARQLService>(dataSourceURI, dataSourceFormat);
        if (tripleFrame) {
            sparqlService->setFrame(tripleFrame);
        }
        return sparqlService;
    } else if (isOntology) {
        auto ontoFile = std::make_shared<OntologyFile>(vocabulary, dataSourceURI, dataSourceFormat);
        if (o_dataSourceLanguage.has_value()) {
            ontoFile->setOntologyLanguage(semweb::ontologyLanguageFromString(o_dataSourceLanguage.value()));
        }
        if (tripleFrame) {
            ontoFile->setFrame(tripleFrame);
        }
        return ontoFile;
    } else {
        return std::make_shared<DataSource>(dataSourceURI, dataSourceFormat, DataSourceType::UNSPECIFIED);
    }
}

create() [2/2]

static std::shared_ptr<DataSource> knowrob::DataSource::create ( const VocabularyPtr &  vocabulary, const boost::property_tree::ptree &  config  )

static

Create a data source from a configuration.

Parameters

vocabulary	the vocabulary of the knowledge base.
config	a property tree used to configure this.

Returns

a data source

dataSourceType() [1/2]

DataSourceType knowrob::DataSource::dataSourceType ( ) const

inline

Returns

the type of the data source.

Definition at line 54 of file DataSource.h.

{ return dataSourceType_; }

dataSourceType() [2/2]

DataSourceType knowrob::DataSource::dataSourceType ( ) const

inline

Returns

the type of the data source.

Definition at line 54 of file DataSource.h.

{ return dataSourceType_; }

format() [1/2]

const auto& knowrob::DataSource::format ( ) const

inline

Returns

string identifier of the data format.

Definition at line 49 of file DataSource.h.

{ return format_; }

format() [2/2]

const auto& knowrob::DataSource::format ( ) const

inline

Returns

string identifier of the data format.

Definition at line 49 of file DataSource.h.

{ return format_; }

getNameFromURI() [1/2]

std::string DataSource::getNameFromURI ( const std::string &  uriString )

static

Ontologies are loaded into named sub-graphs of the knowledge graph. The name is generated from the URI in case of loading RDF files.

Parameters

uriString

A URI pointing to a RDF ontology.

Returns

a graph name for the ontology

Definition at line 36 of file DataSource.cpp.

                                                               {
    return fs::path(uriString).stem();
}

getNameFromURI() [2/2]

static std::string knowrob::DataSource::getNameFromURI ( const std::string &  uriString )

static

Ontologies are loaded into named sub-graphs of the knowledge graph. The name is generated from the URI in case of loading RDF files.

Parameters

uriString

A URI pointing to a RDF ontology.

Returns

a graph name for the ontology

getVersionFromURI() [1/2]

std::string DataSource::getVersionFromURI ( const std::string &  uriString )

static

Extract a version string from an ontology URI. In case the URI points to a local file, the modification time of the file is used as version. For other URIs it is attempted to extract version information from the URI string, if this fails, then the current day is used as a version string.

Parameters

uriString

A URI pointing to a RDF ontology.

Returns

a version string

Definition at line 48 of file DataSource.cpp.

                                                                  {
    fs::path p(uriString);
 
    // check if it is a local existing file and use file modification time
    // as version in this case.
    if (exists(p)) {
        std::ostringstream oss;
        auto stamp = last_write_time(p);
        auto tt = to_time_t(stamp);
        auto tm = *std::localtime(&tt);
        oss << std::put_time(&tm, "%c");
        return oss.str();
    }
 
    // try to extract version from URI
    auto versionString = p.parent_path().filename();
    if (isVersionString(versionString)) {
        return versionString;
    }
 
    // fallback to use the current day as version, thus causing
    // a reload each day.
    {
        std::ostringstream oss;
        auto t = std::time(nullptr);
        auto tm = *std::localtime(&t);
        oss << std::put_time(&tm, "%d-%m-%Y");
        return oss.str();
    }
}

getVersionFromURI() [2/2]

static std::string knowrob::DataSource::getVersionFromURI ( const std::string &  uriString )

static

Extract a version string from an ontology URI. In case the URI points to a local file, the modification time of the file is used as version. For other URIs it is attempted to extract version information from the URI string, if this fails, then the current day is used as a version string.

Parameters

uriString

A URI pointing to a RDF ontology.

Returns

a version string

isVersionString() [1/2]

bool DataSource::isVersionString ( const std::string &  versionString )

static

Parameters

versionString

a string

Returns

true if versionString is a valid version string

Definition at line 79 of file DataSource.cpp.

                                                               {
    // parser rules
    qi::rule<std::string::const_iterator> numbers = (
            (+qi::digit >> '.' >> +qi::digit >> '.' >> +qi::digit) |
            (+qi::digit >> '.' >> +qi::digit));
    // parse input
    auto first = versionString.begin();
    auto last = versionString.end();
    bool r = qi::phrase_parse(first,
                              last,
                              (('v' >> numbers) | numbers),
                              ascii::space);
    // return true if parser succeeded
    return (first == last && r);
}

isVersionString() [2/2]

static bool knowrob::DataSource::isVersionString ( const std::string &  versionString )

static

Parameters

versionString

a string

Returns

true if versionString is a valid version string

name() [1/2]

auto knowrob::DataSource::name ( ) const

inline

Returns

the name of the data source.

Definition at line 59 of file DataSource.h.

{ return getNameFromURI(uri()); }

name() [2/2]

auto knowrob::DataSource::name ( ) const

inline

Returns

the name of the data source.

Definition at line 59 of file DataSource.h.

{ return getNameFromURI(uri()); }

path() [1/2]

const auto& knowrob::DataSource::path ( ) const

inline

Returns

string identifier of the data format.

Definition at line 44 of file DataSource.h.

{ return uri_.path(); }

path() [2/2]

const auto& knowrob::DataSource::path ( ) const

inline

Returns

string identifier of the data format.

Definition at line 44 of file DataSource.h.

{ return uri_.path(); }

uri() [1/2]

const auto& knowrob::DataSource::uri ( ) const

inline

Returns

URI of this data source.

Definition at line 39 of file DataSource.h.

{ return uri_(); }

uri() [2/2]

const auto& knowrob::DataSource::uri ( ) const

inline

Returns

URI of this data source.

Definition at line 39 of file DataSource.h.

{ return uri_(); }

version() [1/2]

auto knowrob::DataSource::version ( ) const

inline

Returns

the version of the data source.

Definition at line 64 of file DataSource.h.

{ return getVersionFromURI(uri()); }

version() [2/2]

auto knowrob::DataSource::version ( ) const

inline

Returns

the version of the data source.

Definition at line 64 of file DataSource.h.

{ return getVersionFromURI(uri()); }

Member Data Documentation

dataSourceType_

DataSourceType knowrob::DataSource::dataSourceType_

protected

Definition at line 101 of file DataSource.h.

format_

std::string knowrob::DataSource::format_

protected

Definition at line 102 of file DataSource.h.

uri_

URI knowrob::DataSource::uri_

protected

Definition at line 103 of file DataSource.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/DataSource.h
• src/DataSource.cpp