@Override
public QueryIterator execEvaluated(
final Binding binding,
PropFuncArg argSubject,
Node predicate,
PropFuncArg argObject,
ExecutionContext execCxt) {
// check subject is a variable.
if (!argSubject.getArg().isVariable()) throw new QueryExecException("Subject not a variable");
final Var var = Var.alloc(argSubject.getArg());
if (!argObject.getArg().isLiteral()) throw new QueryExecException("Subject not a literal");
String searchTerm = argObject.getArg().getLiteralLexicalForm();
Search search = searchEngine();
Iterator<String> x = search.search(searchTerm);
Iter<String> iter = Iter.iter(x);
QueryIterator qIter =
new QueryIterPlainWrapper(
iter.map(
(item) -> {
return BindingFactory.binding(binding, var, NodeFactory.createURI(item));
}));
return qIter;
}
@Override
public void build(
PropFuncArg argSubject, Node predicate, PropFuncArg argObject, ExecutionContext execCxt) {
super.build(argSubject, predicate, argObject, execCxt);
DatasetGraph dsg = execCxt.getDataset();
textIndex = chooseTextIndex(dsg);
if (argSubject.isList()) {
int size = argSubject.getArgListSize();
if (size != 2 && size != 3) {
throw new QueryBuildException(
"Subject has "
+ argSubject.getArgList().size()
+ " elements, not 2 or 3: "
+ argSubject);
}
}
if (argObject.isList()) {
List<Node> list = argObject.getArgList();
if (list.size() == 0) throw new QueryBuildException("Zero-length argument list");
if (list.size() > 4) throw new QueryBuildException("Too many arguments in list : " + list);
// extract of extra lang arg if present and if is usable.
// arg is removed from the list to avoid conflict with order and args length
langArg = extractArg("lang", list);
if (langArg != null && textIndex.getDocDef().getLangField() == null)
log.warn("lang argument is ignored if langField not set in the index configuration");
}
}
private static void argList(ExprList exprList, PropFuncArg pfArg) {
if (pfArg.isNode()) {
Node n = pfArg.getArg();
Expr expr = ExprUtils.nodeToExpr(n);
exprList.add(expr);
return;
}
for (Node n : pfArg.getArgList()) {
Expr expr = ExprUtils.nodeToExpr(n);
exprList.add(expr);
}
}
/**
* Deconstruct the node or list object argument and make a StrMatch The 'executionTime' flag
* indciates whether this is for a build time static check, or for runtime execution.
*/
private StrMatch objectToStruct(PropFuncArg argObject, boolean executionTime) {
EntityDefinition docDef = textIndex.getDocDef();
if (argObject.isNode()) {
Node o = argObject.getArg();
if (!o.isLiteral()) {
if (executionTime) log.warn("Object to text query is not a literal");
return null;
}
RDFDatatype dt = o.getLiteralDatatype();
if (dt != null && dt != XSDDatatype.XSDstring) {
log.warn("Object to text query is not a string");
return null;
}
String qs = o.getLiteralLexicalForm();
return new StrMatch(null, qs, -1, 0);
}
List<Node> list = argObject.getArgList();
if (list.size() == 0 || list.size() > 3)
throw new TextIndexException("Change in object list size");
Node predicate = null;
String field = null; // Do not prepend the field name - rely on default field
int idx = 0;
Node x = list.get(0);
// Property?
if (x.isURI()) {
predicate = x;
idx++;
if (idx >= list.size())
throw new TextIndexException("Property specificed but no query string : " + list);
x = list.get(idx);
field = docDef.getField(predicate);
if (field == null) {
log.warn("Predicate not indexed: " + predicate);
return null;
}
}
// String!
if (!x.isLiteral()) {
if (executionTime) log.warn("Text query string is not a literal " + list);
return null;
}
if (x.getLiteralDatatype() != null && !x.getLiteralDatatype().equals(XSDDatatype.XSDstring)) {
log.warn("Text query is not a string " + list);
return null;
}
String queryString = x.getLiteralLexicalForm();
idx++;
int limit = -1;
float score = 0;
if (idx < list.size()) {
// Limit?
x = list.get(idx);
idx++;
if (!x.isLiteral()) {
if (executionTime) log.warn("Text query limit is not an integer " + x);
return null;
}
int v = NodeFactoryExtra.nodeToInt(x);
limit = (v < 0) ? -1 : v;
}
String qs = queryString;
if (field != null) qs = field + ":" + qs;
return new StrMatch(predicate, qs, limit, score);
}
@Override
public QueryIterator exec(
Binding binding,
PropFuncArg argSubject,
Node predicate,
PropFuncArg argObject,
ExecutionContext execCxt) {
if (textIndex == null) {
if (!warningIssued) {
Log.warn(getClass(), "No text index - no text search performed");
warningIssued = true;
}
// Not a text dataset - no-op
return IterLib.result(binding, execCxt);
}
DatasetGraph dsg = execCxt.getDataset();
argSubject = Substitute.substitute(argSubject, binding);
argObject = Substitute.substitute(argObject, binding);
Node s = null;
Node score = null;
Node literal = null;
if (argSubject.isList()) {
// Length checked in build()
s = argSubject.getArg(0);
score = argSubject.getArg(1);
if (!score.isVariable())
throw new QueryExecException("Hit score is not a variable: " + argSubject);
if (argSubject.getArgListSize() > 2) {
literal = argSubject.getArg(2);
if (!literal.isVariable())
throw new QueryExecException("Hit literal is not a variable: " + argSubject);
}
} else {
s = argSubject.getArg();
}
if (s.isLiteral())
// Does not match
return IterLib.noResults(execCxt);
StrMatch match = objectToStruct(argObject, true);
if (match == null) {
// can't match
return IterLib.noResults(execCxt);
}
// ----
QueryIterator qIter =
(Var.isVar(s))
? variableSubject(binding, s, score, literal, match, execCxt)
: concreteSubject(binding, s, score, literal, match, execCxt);
if (match.getLimit() >= 0) qIter = new QueryIterSlice(qIter, 0, match.getLimit(), execCxt);
return qIter;
}
