SOLR-877: Add access to TermEnum capabilities via TermsComponent

git-svn-id: https://svn.apache.org/repos/asf/lucene/solr/trunk@721491 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -91,6 +91,8 @@ New Features
 17. SOLR-829: Allow slaves to request compressed files from master during replication
     (Simon Collins, Noble Paul, Akshay Ukey via shalin)
 
+18. SOLR-877: Added TermsComponent for accessing Lucene's TermEnum capabilities.
+    Useful for auto suggest and possibly distributed search.  Not distributed search compliant.  (gsingers)
 
 Optimizations
 ----------------------

example/solr/conf/solrconfig.xml

@@ -610,6 +610,15 @@
   </requestHandler>
 
 
+  <searchComponent name="termsComp" class="org.apache.solr.handler.component.TermsComponent"/>
+
+  <requestHandler name="/autoSuggest" class="org.apache.solr.handler.component.SearchHandler">
+    <arr name="components">
+      <str>termsComp</str>
+    </arr>
+  </requestHandler>
+
+
   <!-- a search component that enables you to configure the top results for
        a given query regardless of the normal lucene scoring.-->
   <searchComponent name="elevator" class="solr.QueryElevationComponent" >

src/java/org/apache/solr/common/params/TermsParams.java

@@ -0,0 +1,62 @@
+package org.apache.solr.common.params;
+/**
+ * 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.
+ */
+
+
+/**
+ *
+ *
+ **/
+public class TermsParams {
+
+  public static final String TERMS = "terms";
+
+  public static final String TERMS_PREFIX = TERMS + ".";
+
+  /**
+   * Required.  Specify the field to look up terms in.
+   */
+  public static final String TERMS_FIELD = TERMS_PREFIX + "fl";
+
+  /**
+   * Optional.  The lower bound term to start at.  The TermEnum will start at the next term after this term in the dictionary.
+   *
+   * If not specified, the empty string is used
+   */
+  public static final String TERMS_LOWER = TERMS_PREFIX + "lower";
+
+  /**
+   * Optional.  The term to stop at.
+   *
+   * @see #TERMS_UPPER_INCLUSIVE
+   */
+  public static final String TERMS_UPPER = TERMS_PREFIX + "upper";
+  /**
+   * Optional.  If true, include the upper bound term in the results.  False by default.
+   */
+  public static final String TERMS_UPPER_INCLUSIVE = TERMS_PREFIX + "upr.incl";
+
+  /**
+   * Optional.  If true, include the lower bound term in the results, otherwise skip to the next one.  True by default.
+   */
+  public static final String TERMS_LOWER_INCLUSIVE = TERMS_PREFIX + "lwr.incl";
+
+  /**
+   * Optional.  The number of results to return.  If not specified, looks for {@link org.apache.solr.common.params.CommonParams#ROWS}.  If that's not specified, uses 10.
+   */
+  public static final String TERMS_ROWS = TERMS_PREFIX + "rows";
+}

src/java/org/apache/solr/handler/component/TermsComponent.java

@@ -0,0 +1,101 @@
+package org.apache.solr.handler.component;
+/**
+ * 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.
+ */
+
+import org.apache.lucene.index.Term;
+import org.apache.lucene.index.TermEnum;
+import org.apache.solr.common.SolrException;
+import org.apache.solr.common.params.CommonParams;
+import org.apache.solr.common.params.SolrParams;
+import org.apache.solr.common.params.TermsParams;
+import org.apache.solr.common.util.NamedList;
+
+import java.io.IOException;
+
+
+/**
+ * Return TermEnum information, useful for things like auto suggest.
+ *
+ * @see org.apache.solr.common.params.TermsParams
+ * See Lucene's TermEnum class
+ */
+public class TermsComponent extends SearchComponent {
+
+
+  public void process(ResponseBuilder rb) throws IOException {
+    SolrParams params = rb.req.getParams();
+    if (params.getBool(TermsParams.TERMS, false)) {
+      String lower = params.get(TermsParams.TERMS_LOWER, "");
+      String field = params.get(TermsParams.TERMS_FIELD);
+      if (field != null) {
+        Term lowerTerm = new Term(field, lower);
+        TermEnum termEnum = rb.req.getSearcher().getReader().terms(lowerTerm);//this will be positioned ready to go
+        int rows = params.getInt(TermsParams.TERMS_ROWS, params.getInt(CommonParams.ROWS, 10));
+        int i = 0;
+        NamedList terms = new NamedList();
+        rb.rsp.add("terms", terms);
+        String upper = params.get(TermsParams.TERMS_UPPER);
+        Term upperTerm = upper != null ? new Term(field, upper) : null;
+        boolean upperIncl = params.getBool(TermsParams.TERMS_UPPER_INCLUSIVE, false);
+        boolean lowerIncl = params.getBool(TermsParams.TERMS_LOWER_INCLUSIVE, true);
+        boolean hasMore = true;
+        if (lowerIncl == false) {
+          hasMore = termEnum.next();
+        }
+        if (hasMore == true) {
+          do {
+            Term theTerm = termEnum.term();
+            String theText = theTerm.text();
+            int upperCmp = upperTerm != null ? theTerm.compareTo(upperTerm) : -1;
+            if (theTerm != null && theTerm.field().equals(field)
+                    && ((upperIncl == true && upperCmp <= 0) ||
+                    (upperIncl == false && upperCmp < 0))) {
+              terms.add(theText, String.valueOf(termEnum.docFreq()));
+            } else {//we're done
+              break;
+            }
+            i++;
+          }
+          while (i < rows && termEnum.next());
+        }
+        termEnum.close();
+      } else {
+        throw new SolrException(SolrException.ErrorCode.BAD_REQUEST, "No terms.fl parameter specified");
+      }
+    }
+  }
+
+  public void prepare(ResponseBuilder rb) throws IOException {
+    //nothing to do
+  }
+
+  public String getVersion() {
+    return "$Revision$";
+  }
+
+  public String getSourceId() {
+    return "$Id:$";
+  }
+
+  public String getSource() {
+    return "$Revision:$";
+  }
+
+  public String getDescription() {
+    return "A Component for working with Term Enumerators";
+  }
+}

src/test/org/apache/solr/handler/component/TermsComponentTest.java

@@ -0,0 +1,203 @@
+package org.apache.solr.handler.component;
+/**
+ * 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.
+ */
+
+import org.mortbay.log.Log;
+import org.apache.solr.util.AbstractSolrTestCase;
+import org.apache.solr.core.SolrCore;
+import org.apache.solr.common.params.ModifiableSolrParams;
+import org.apache.solr.common.params.TermsParams;
+import org.apache.solr.common.util.SimpleOrderedMap;
+import org.apache.solr.common.util.NamedList;
+import org.apache.solr.request.SolrRequestHandler;
+import org.apache.solr.request.LocalSolrQueryRequest;
+import org.apache.solr.request.SolrQueryResponse;
+
+import java.util.Iterator;
+
+
+/**
+ *
+ *
+ **/
+public class TermsComponentTest extends AbstractSolrTestCase {
+  public String getSchemaFile() {
+    return "schema.xml";
+  }
+
+  public String getSolrConfigFile() {
+    return "solrconfig.xml";
+  }
+
+  public void setUp() throws Exception {
+    super.setUp();
+
+    assertU(adoc("id", "0", "lowerfilt", "a"));
+    assertU(adoc("id", "1", "lowerfilt", "a"));
+    assertU(adoc("id", "2", "lowerfilt", "aa"));
+    assertU(adoc("id", "3", "lowerfilt", "aaa"));
+    assertU(adoc("id", "4", "lowerfilt", "ab"));
+    assertU(adoc("id", "5", "lowerfilt", "abb"));
+    assertU(adoc("id", "6", "lowerfilt", "abc"));
+    assertU(adoc("id", "7", "lowerfilt", "b"));
+    assertU(adoc("id", "8", "lowerfilt", "baa"));
+    assertU(adoc("id", "9", "lowerfilt", "bbb"));
+
+    assertU("commit", commit());
+  }
+
+  public void testEmptyLower() throws Exception {
+    SolrCore core = h.getCore();
+    TermsComponent tc = (TermsComponent) core.getSearchComponent("termsComp");
+    assertTrue("tc is null and it shouldn't be", tc != null);
+
+    ModifiableSolrParams params = new ModifiableSolrParams();
+    params.add(TermsParams.TERMS, "true");
+    params.add(TermsParams.TERMS_FIELD, "lowerfilt");
+    //no lower bound
+    params.add(TermsParams.TERMS_UPPER, "b");
+    params.add(TermsParams.TERMS_ROWS, String.valueOf(50));
+    SolrRequestHandler handler;
+    SolrQueryResponse rsp;
+    NamedList values;
+    NamedList terms;
+    handler = core.getRequestHandler("/terms");
+    assertTrue("handler is null and it shouldn't be", handler != null);
+    rsp = new SolrQueryResponse();
+    rsp.add("responseHeader", new SimpleOrderedMap());
+    handler.handleRequest(new LocalSolrQueryRequest(core, params), rsp);
+    values = rsp.getValues();
+    terms = (NamedList) values.get("terms");
+    assertTrue("terms Size: " + terms.size() + " is not: " + 6, terms.size() == 6);
+    assertTrue("a is null and it shouldn't be", terms.get("a") != null);
+    assertTrue("aa is null and it shouldn't be", terms.get("aa") != null);
+    assertTrue("aaa is null and it shouldn't be", terms.get("aaa") != null);
+    assertTrue("ab is null and it shouldn't be", terms.get("ab") != null);
+    assertTrue("abb is null and it shouldn't be", terms.get("abb") != null);
+    assertTrue("abc is null and it shouldn't be", terms.get("abc") != null);
+  }
+
+  public void testPastUpper() throws Exception {
+    SolrCore core = h.getCore();
+    TermsComponent tc = (TermsComponent) core.getSearchComponent("termsComp");
+    assertTrue("tc is null and it shouldn't be", tc != null);
+
+    ModifiableSolrParams params = new ModifiableSolrParams();
+    params.add(TermsParams.TERMS, "true");
+    params.add(TermsParams.TERMS_FIELD, "lowerfilt");
+    //no lower bound
+    params.add(TermsParams.TERMS_LOWER, "d");
+    params.add(TermsParams.TERMS_ROWS, String.valueOf(50));
+    SolrRequestHandler handler;
+    SolrQueryResponse rsp;
+    NamedList values;
+    NamedList terms;
+    handler = core.getRequestHandler("/terms");
+    assertTrue("handler is null and it shouldn't be", handler != null);
+    rsp = new SolrQueryResponse();
+    rsp.add("responseHeader", new SimpleOrderedMap());
+    handler.handleRequest(new LocalSolrQueryRequest(core, params), rsp);
+    values = rsp.getValues();
+    terms = (NamedList) values.get("terms");
+    assertTrue("terms Size: " + terms.size() + " is not: " + 0, terms.size() == 0);
+  }
+
+  public void test() throws Exception {
+    SolrCore core = h.getCore();
+    TermsComponent tc = (TermsComponent) core.getSearchComponent("termsComp");
+    assertTrue("tc is null and it shouldn't be", tc != null);
+
+    ModifiableSolrParams params = new ModifiableSolrParams();
+    params.add(TermsParams.TERMS, "true");
+    params.add(TermsParams.TERMS_FIELD, "lowerfilt");
+    params.add(TermsParams.TERMS_LOWER, "a");
+    params.add(TermsParams.TERMS_UPPER, "b");
+    params.add(TermsParams.TERMS_ROWS, String.valueOf(50));
+    SolrRequestHandler handler;
+    SolrQueryResponse rsp;
+    NamedList values;
+    NamedList terms;
+    handler = core.getRequestHandler("/terms");
+    assertTrue("handler is null and it shouldn't be", handler != null);
+    rsp = new SolrQueryResponse();
+    rsp.add("responseHeader", new SimpleOrderedMap());
+    handler.handleRequest(new LocalSolrQueryRequest(core, params), rsp);
+    values = rsp.getValues();
+    terms = (NamedList) values.get("terms");
+    assertTrue("terms Size: " + terms.size() + " is not: " + 6, terms.size() == 6);
+    assertTrue("aa is null and it shouldn't be", terms.get("aa") != null);
+    assertTrue("aaa is null and it shouldn't be", terms.get("aaa") != null);
+    assertTrue("ab is null and it shouldn't be", terms.get("ab") != null);
+    assertTrue("abb is null and it shouldn't be", terms.get("abb") != null);
+    assertTrue("abc is null and it shouldn't be", terms.get("abc") != null);
+    assertTrue("a is null", terms.get("a") != null);
+    assertTrue("b is not null and it should be", terms.get("b") == null);
+
+    params.add(TermsParams.TERMS_UPPER_INCLUSIVE, "true");
+    rsp = new SolrQueryResponse();
+    rsp.add("responseHeader", new SimpleOrderedMap());
+    handler.handleRequest(new LocalSolrQueryRequest(core, params), rsp);
+    values = rsp.getValues();
+    terms = (NamedList) values.get("terms");
+    assertTrue("terms Size: " + terms.size() + " is not: " + 7, terms.size() == 7);
+    assertTrue("aa is null and it shouldn't be", terms.get("aa") != null);
+    assertTrue("ab is null and it shouldn't be", terms.get("ab") != null);
+    assertTrue("aaa is null and it shouldn't be", terms.get("aaa") != null);
+    assertTrue("abb is null and it shouldn't be", terms.get("abb") != null);
+    assertTrue("abc is null and it shouldn't be", terms.get("abc") != null);
+    assertTrue("b is null and it shouldn't be", terms.get("b") != null);
+    assertTrue("a is null", terms.get("a") != null);
+    assertTrue("baa is not null", terms.get("baa") == null);
+
+    params.add(TermsParams.TERMS_LOWER_INCLUSIVE, "false");
+    rsp = new SolrQueryResponse();
+    rsp.add("responseHeader", new SimpleOrderedMap());
+    handler.handleRequest(new LocalSolrQueryRequest(core, params), rsp);
+    values = rsp.getValues();
+    terms = (NamedList) values.get("terms");
+    assertTrue("terms Size: " + terms.size() + " is not: " + 6, terms.size() == 6);
+    assertTrue("aa is null and it shouldn't be", terms.get("aa") != null);
+    assertTrue("ab is null and it shouldn't be", terms.get("ab") != null);
+    assertTrue("aaa is null and it shouldn't be", terms.get("aaa") != null);
+    assertTrue("abb is null and it shouldn't be", terms.get("abb") != null);
+    assertTrue("abc is null and it shouldn't be", terms.get("abc") != null);
+    assertTrue("b is null and it shouldn't be", terms.get("b") != null);
+    assertTrue("a is not null", terms.get("a") == null);
+    assertTrue("baa is not null", terms.get("baa") == null);
+
+
+
+    params = new ModifiableSolrParams();
+    params.add(TermsParams.TERMS, "true");
+    params.add(TermsParams.TERMS_FIELD, "lowerfilt");
+    params.add(TermsParams.TERMS_LOWER, "a");
+    params.add(TermsParams.TERMS_UPPER, "b");
+    params.add(TermsParams.TERMS_ROWS, String.valueOf(2));
+    rsp = new SolrQueryResponse();
+    rsp.add("responseHeader", new SimpleOrderedMap());
+    handler.handleRequest(new LocalSolrQueryRequest(core, params), rsp);
+    values = rsp.getValues();
+    terms = (NamedList) values.get("terms");
+    assertTrue("terms Size: " + terms.size() + " is not: " + 2, terms.size() == 2);
+    assertTrue("aa is null and it shouldn't be", terms.get("a") != null);
+    assertTrue("aaa is null and it shouldn't be", terms.get("aa") != null);
+    assertTrue("abb is not null", terms.get("abb") == null);
+    assertTrue("abc is not null", terms.get("abc") == null);
+    assertTrue("b is null and it shouldn't be", terms.get("b") == null);
+    assertTrue("baa is not null", terms.get("baa") == null);
+  }
+}

src/test/test-files/solr/conf/solrconfig.xml

@@ -349,6 +349,14 @@
       <str name="spellcheckIndexDir">spellchecker3</str>
     </lst>
   </searchComponent>
+
+  <searchComponent name="termsComp" class="org.apache.solr.handler.component.TermsComponent"/>
+
+  <requestHandler name="/terms" class="org.apache.solr.handler.component.SearchHandler">
+    <arr name="components">
+      <str>termsComp</str>
+    </arr>
+  </requestHandler>
   <!--
   The SpellingQueryConverter to convert raw (CommonParams.Q) queries into tokens.  Uses a simple regular expression
    to strip off field markup, boosts, ranges, etc. but it is not guaranteed to match an exact parse from the query parser.