Mercurial > hg > svcore
view rdf/SimpleSPARQLQuery.cpp @ 446:aa190a6a2625
* More SelectableLabel and TransformFinder tweaking
author | Chris Cannam |
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date | Mon, 29 Sep 2008 15:06:43 +0000 |
parents | 5746c559af15 |
children | a75edaa08d28 |
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/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*- vi:set ts=8 sts=4 sw=4: */ /* Sonic Visualiser An audio file viewer and annotation editor. Centre for Digital Music, Queen Mary, University of London. This file copyright 2008 QMUL. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. See the file COPYING included with this distribution for more information. */ #include "SimpleSPARQLQuery.h" #include "base/ProgressReporter.h" #ifdef USE_NEW_RASQAL_API #include <rasqal/rasqal.h> #else #include <rasqal.h> #endif #include <iostream> using std::cerr; using std::endl; #ifdef USE_NEW_RASQAL_API class WrasqalWorldWrapper // wrong but wromantic, etc { public: WrasqalWorldWrapper() : m_world(rasqal_new_world()) { } ~WrasqalWorldWrapper() { rasqal_free_world(m_world); } rasqal_world *getWorld() const { return m_world; } private: rasqal_world *m_world; }; #endif class SimpleSPARQLQuery::Impl { public: Impl(QString query); ~Impl(); void setProgressReporter(ProgressReporter *reporter) { m_reporter = reporter; } bool wasCancelled() const { return m_cancelled; } ResultList execute(); bool isOK() const; QString getErrorString() const; protected: static void errorHandler(void *, raptor_locator *, const char *); #ifdef USE_NEW_RASQAL_API static WrasqalWorldWrapper m_www; #else static bool m_initialised; #endif QString m_query; QString m_errorString; ProgressReporter *m_reporter; bool m_cancelled; }; #ifdef USE_NEW_RASQAL_API WrasqalWorldWrapper SimpleSPARQLQuery::Impl::m_www; #else bool SimpleSPARQLQuery::Impl::m_initialised = false; #endif SimpleSPARQLQuery::SimpleSPARQLQuery(QString query) : m_impl(new Impl(query)) { } SimpleSPARQLQuery::~SimpleSPARQLQuery() { delete m_impl; } void SimpleSPARQLQuery::setProgressReporter(ProgressReporter *reporter) { m_impl->setProgressReporter(reporter); } bool SimpleSPARQLQuery::wasCancelled() const { return m_impl->wasCancelled(); } SimpleSPARQLQuery::ResultList SimpleSPARQLQuery::execute() { return m_impl->execute(); } bool SimpleSPARQLQuery::isOK() const { return m_impl->isOK(); } QString SimpleSPARQLQuery::getErrorString() const { return m_impl->getErrorString(); } SimpleSPARQLQuery::Impl::Impl(QString query) : m_query(query), m_reporter(0), m_cancelled(false) { } SimpleSPARQLQuery::Impl::~Impl() { } bool SimpleSPARQLQuery::Impl::isOK() const { return (m_errorString == ""); } QString SimpleSPARQLQuery::Impl::getErrorString() const { return m_errorString; } void SimpleSPARQLQuery::Impl::errorHandler(void *data, raptor_locator *locator, const char *message) { SimpleSPARQLQuery::Impl *impl = (SimpleSPARQLQuery::Impl *)data; // char buffer[256]; // raptor_format_locator(buffer, 255, locator); // impl->m_errorString = QString("%1 - %2").arg(buffer).arg(message); impl->m_errorString = message; cerr << "SimpleSPARQLQuery: ERROR: " << impl->m_errorString.toStdString() << endl; } SimpleSPARQLQuery::ResultList SimpleSPARQLQuery::Impl::execute() { ResultList list; #ifdef USE_NEW_RASQAL_API rasqal_query *query = rasqal_new_query(m_www.getWorld(), "sparql", NULL); #else if (!m_initialised) { m_initialised = true; rasqal_init(); } rasqal_query *query = rasqal_new_query("sparql", NULL); #endif if (!query) { m_errorString = "Failed to construct query"; cerr << "SimpleSPARQLQuery: ERROR: " << m_errorString.toStdString() << endl; return list; } rasqal_query_set_error_handler(query, this, errorHandler); rasqal_query_set_fatal_error_handler(query, this, errorHandler); if (rasqal_query_prepare (query, (const unsigned char *)m_query.toUtf8().data(), NULL)) { cerr << "SimpleSPARQLQuery: Failed to prepare query" << endl; rasqal_free_query(query); return list; } rasqal_query_results *results = rasqal_query_execute(query); // cerr << "Query executed" << endl; if (!results) { cerr << "SimpleSPARQLQuery: RASQAL query failed" << endl; rasqal_free_query(query); return list; } if (!rasqal_query_results_is_bindings(results)) { cerr << "SimpleSPARQLQuery: RASQAL query has wrong result type (not bindings)" << endl; rasqal_free_query_results(results); rasqal_free_query(query); return list; } int resultCount = 0; int resultTotal = rasqal_query_results_get_count(results); // probably wrong m_cancelled = false; while (!rasqal_query_results_finished(results)) { int count = rasqal_query_results_get_bindings_count(results); KeyValueMap resultmap; for (int i = 0; i < count; ++i) { const unsigned char *name = rasqal_query_results_get_binding_name(results, i); rasqal_literal *literal = rasqal_query_results_get_binding_value(results, i); QString key = (const char *)name; if (!literal) { resultmap[key] = Value(); continue; } ValueType type = LiteralValue; if (literal->type == RASQAL_LITERAL_URI) type = URIValue; else if (literal->type == RASQAL_LITERAL_BLANK) type = BlankValue; QString text = (const char *)rasqal_literal_as_string(literal); resultmap[key] = Value(type, text); } list.push_back(resultmap); rasqal_query_results_next(results); resultCount++; if (m_reporter) { if (resultCount >= resultTotal) { if (m_reporter->isDefinite()) m_reporter->setDefinite(false); m_reporter->setProgress(resultCount); } else { m_reporter->setProgress((resultCount * 100) / resultTotal); } if (m_reporter->wasCancelled()) { m_cancelled = true; break; } } } rasqal_free_query_results(results); rasqal_free_query(query); return list; } SimpleSPARQLQuery::Value SimpleSPARQLQuery::singleResultQuery(QString query, QString binding) { SimpleSPARQLQuery q(query); ResultList results = q.execute(); if (!q.isOK()) { cerr << "SimpleSPARQLQuery::singleResultQuery: ERROR: " << q.getErrorString().toStdString() << endl; return Value(); } if (results.empty()) { return Value(); } for (int i = 0; i < results.size(); ++i) { if (results[i].find(binding) != results[i].end() && results[i][binding].type != NoValue) { return results[i][binding]; } } return Value(); }