/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.solr.search;
import org.apache.solr.search.function.FunctionQuery;
import org.apache.solr.search.function.ValueSource;
import org.apache.solr.search.function.valuesource.*;
import org.apache.lucene.search.Query;
import org.apache.solr.common.params.SolrParams;
import org.apache.solr.request.SolrQueryRequest;
import org.apache.solr.schema.SchemaField;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
public class FunctionQParser extends QParser {
/** @lucene.internal */
public QueryParsing.StrParser sp;
boolean parseMultipleSources = true;
boolean parseToEnd = true;
public FunctionQParser(String qstr, SolrParams localParams, SolrParams params, SolrQueryRequest req) {
super(qstr, localParams, params, req);
}
public void setParseMultipleSources(boolean parseMultipleSources) {
this.parseMultipleSources = parseMultipleSources;
}
/** parse multiple comma separated value sources */
public boolean getParseMultipleSources() {
return parseMultipleSources;
}
public void setParseToEnd(boolean parseToEnd) {
this.parseToEnd = parseToEnd;
}
/** throw exception if there is extra stuff at the end of the parsed valuesource(s). */
public boolean getParseToEnd() {
return parseMultipleSources;
}
@Override
public Query parse() throws SyntaxError {
sp = new QueryParsing.StrParser(getString());
ValueSource vs = null;
List<ValueSource> lst = null;
for(;;) {
ValueSource valsource = parseValueSource(false);
sp.eatws();
if (!parseMultipleSources) {
vs = valsource;
break;
} else {
if (lst != null) {
lst.add(valsource);
} else {
vs = valsource;
}
}
// check if there is a "," separator
if (sp.peek() != ',') break;
consumeArgumentDelimiter();
if (lst == null) {
lst = new ArrayList<>(2);
lst.add(valsource);
}
}
if (parseToEnd && sp.pos < sp.end) {
throw new SyntaxError("Unexpected text after function: " + sp.val.substring(sp.pos, sp.end));
}
if (lst != null) {
vs = new VectorValueSource(lst);
}
return new FunctionQuery(vs);
}
/**
* Are there more arguments in the argument list being parsed?
*
* @return whether more args exist
*/
public boolean hasMoreArguments() throws SyntaxError {
int ch = sp.peek();
/* determine whether the function is ending with a paren or end of str */
return (! (ch == 0 || ch == ')') );
}
/*
* TODO: Doc
*/
public String parseId() throws SyntaxError {
String value = parseArg();
if (argWasQuoted) throw new SyntaxError("Expected identifier instead of quoted string:" + value);
return value;
}
/**
* Parse a float.
*
* @return Float
*/
public Float parseFloat() throws SyntaxError {
String str = parseArg();
if (argWasQuoted()) throw new SyntaxError("Expected float instead of quoted string:" + str);
float value = Float.parseFloat(str);
return value;
}
/**
* Parse a Double
* @return double
*/
public double parseDouble() throws SyntaxError {
String str = parseArg();
if (argWasQuoted()) throw new SyntaxError("Expected double instead of quoted string:" + str);
double value = Double.parseDouble(str);
return value;
}
/**
* Parse an integer
* @return An int
*/
public int parseInt() throws SyntaxError {
String str = parseArg();
if (argWasQuoted()) throw new SyntaxError("Expected double instead of quoted string:" + str);
int value = Integer.parseInt(str);
return value;
}
private boolean argWasQuoted;
public boolean argWasQuoted() {
return argWasQuoted;
}
public String parseArg() throws SyntaxError {
argWasQuoted = false;
sp.eatws();
char ch = sp.peek();
String val = null;
switch (ch) {
case ')': return null;
case '$':
sp.pos++;
String param = sp.getId();
val = getParam(param);
break;
case '\'':
case '"':
val = sp.getQuotedString();
argWasQuoted = true;
break;
default:
// read unquoted literal ended by whitespace ',' or ')'
// there is no escaping.
int valStart = sp.pos;
for (;;) {
if (sp.pos >= sp.end) {
throw new SyntaxError("Missing end to unquoted value starting at " + valStart + " str='" + sp.val +"'");
}
char c = sp.val.charAt(sp.pos);
if (c==')' || c==',' || Character.isWhitespace(c)) {
val = sp.val.substring(valStart, sp.pos);
break;
}
sp.pos++;
}
}
sp.eatws();
consumeArgumentDelimiter();
return val;
}
/**
* Parse a list of ValueSource. Must be the final set of arguments
* to a ValueSource.
*
* @return List<ValueSource>
*/
public List<ValueSource> parseValueSourceList() throws SyntaxError {
List<ValueSource> sources = new ArrayList<>(3);
while (hasMoreArguments()) {
sources.add(parseValueSource(true));
}
return sources;
}
/**
* Parse an individual ValueSource.
*/
public ValueSource parseValueSource() throws SyntaxError {
/* consume the delimiter afterward for an external call to parseValueSource */
return parseValueSource(true);
}
/*
* TODO: Doc
*/
public Query parseNestedQuery() throws SyntaxError {
Query nestedQuery;
if (sp.opt("$")) {
String param = sp.getId();
String qstr = getParam(param);
qstr = qstr==null ? "" : qstr;
nestedQuery = subQuery(qstr, null).getQuery();
}
else {
int start = sp.pos;
String v = sp.val;
String qs = v;
HashMap nestedLocalParams = new HashMap<String,String>();
int end = QueryParsing.parseLocalParams(qs, start, nestedLocalParams, getParams());
QParser sub;
if (end>start) {
if (nestedLocalParams.get(QueryParsing.V) != null) {
// value specified directly in local params... so the end of the
// query should be the end of the local params.
sub = subQuery(qs.substring(start, end), null);
} else {
// value here is *after* the local params... ask the parser.
sub = subQuery(qs, null);
// int subEnd = sub.findEnd(')');
// TODO.. implement functions to find the end of a nested query
throw new SyntaxError("Nested local params must have value in v parameter. got '" + qs + "'");
}
} else {
throw new SyntaxError("Nested function query must use $param or {!v=value} forms. got '" + qs + "'");
}
sp.pos += end-start; // advance past nested query
nestedQuery = sub.getQuery();
}
consumeArgumentDelimiter();
return nestedQuery;
}
/**
* Parse an individual value source.
*
* @param doConsumeDelimiter whether to consume a delimiter following the ValueSource
*/
protected ValueSource parseValueSource(boolean doConsumeDelimiter) throws SyntaxError {
ValueSource valueSource;
int ch = sp.peek();
if (ch>='0' && ch<='9' || ch=='.' || ch=='+' || ch=='-') {
Number num = sp.getNumber();
if (num instanceof Long) {
valueSource = new LongConstValueSource(num.longValue());
} else if (num instanceof Double) {
valueSource = new DoubleConstValueSource(num.doubleValue());
} else {
// shouldn't happen
valueSource = new ConstValueSource(num.floatValue());
}
} else if (ch == '"' || ch == '\''){
valueSource = new LiteralValueSource(sp.getQuotedString());
} else if (ch == '$') {
sp.pos++;
String param = sp.getId();
String val = getParam(param);
if (val == null) {
throw new SyntaxError("Missing param " + param + " while parsing function '" + sp.val + "'");
}
QParser subParser = subQuery(val, "func");
if (subParser instanceof FunctionQParser) {
((FunctionQParser)subParser).setParseMultipleSources(true);
}
Query subQuery = subParser.getQuery();
if (subQuery instanceof FunctionQuery) {
valueSource = ((FunctionQuery) subQuery).getValueSource();
} else {
valueSource = new QueryValueSource(subQuery, 0.0f);
}
/***
// dereference *simple* argument (i.e., can't currently be a function)
// In the future we could support full function dereferencing via a stack of ValueSource (or StringParser) objects
ch = val.length()==0 ? '\0' : val.charAt(0);
if (ch>='0' && ch<='9' || ch=='.' || ch=='+' || ch=='-') {
QueryParsing.StrParser sp = new QueryParsing.StrParser(val);
Number num = sp.getNumber();
if (num instanceof Long) {
valueSource = new LongConstValueSource(num.longValue());
} else if (num instanceof Double) {
valueSource = new DoubleConstValueSource(num.doubleValue());
} else {
// shouldn't happen
valueSource = new ConstValueSource(num.floatValue());
}
} else if (ch == '"' || ch == '\'') {
QueryParsing.StrParser sp = new QueryParsing.StrParser(val);
val = sp.getQuotedString();
valueSource = new LiteralValueSource(val);
} else {
if (val.length()==0) {
valueSource = new LiteralValueSource(val);
} else {
String id = val;
SchemaField f = req.getSchema().getField(id);
valueSource = f.getType().getValueSource(f, this);
}
}
***/
} else {
String id = sp.getId();
if (sp.opt("(")) {
// a function... look it up.
ValueSourceParser argParser = req.getCore().getValueSourceParser(id);
if (argParser==null) {
throw new SyntaxError("Unknown function " + id + " in FunctionQuery(" + sp + ")");
}
valueSource = argParser.parse(this);
sp.expect(")");
}
else {
if ("true".equals(id)) {
valueSource = new BoolConstValueSource(true);
} else if ("false".equals(id)) {
valueSource = new BoolConstValueSource(false);
} else {
SchemaField f = req.getSchema().getField(id);
valueSource = f.getType().getValueSource(f, this);
}
}
}
if (doConsumeDelimiter)
consumeArgumentDelimiter();
return valueSource;
}
/**
* Consume an argument delimiter (a comma) from the token stream.
* Only consumes if more arguments should exist (no ending parens or end of string).
*
* @return whether a delimiter was consumed
*/
protected boolean consumeArgumentDelimiter() throws SyntaxError {
/* if a list of args is ending, don't expect the comma */
if (hasMoreArguments()) {
sp.expect(",");
return true;
}
return false;
}
}