Skip to content

Commit

Permalink
New _tier metadata field that supports term, terms, exists and wildca…
Browse files Browse the repository at this point in the history
…rd queries on the first data tier preference stated for an index.

Backport of 3aee4c1

Closes elastic#68135
  • Loading branch information
markharwood committed Apr 7, 2021
1 parent b4e19a2 commit 08a188d
Show file tree
Hide file tree
Showing 5 changed files with 259 additions and 1 deletion.
6 changes: 6 additions & 0 deletions docs/reference/mapping/fields.asciidoc
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,10 @@ some of these metadata fields can be customized when a mapping type is created.

The document's mapping type.

<<mapping-tier-field,`_tier`>>::

The current data tier preference of the index to which the document belongs.

<<mapping-id-field,`_id`>>::

The document's ID.
Expand Down Expand Up @@ -76,6 +80,8 @@ include::fields/id-field.asciidoc[]

include::fields/index-field.asciidoc[]

include::fields/tier-field.asciidoc[]

include::fields/meta-field.asciidoc[]

include::fields/routing-field.asciidoc[]
Expand Down
44 changes: 44 additions & 0 deletions docs/reference/mapping/fields/tier-field.asciidoc
Original file line number Diff line number Diff line change
@@ -0,0 +1,44 @@
[[mapping-tier-field]]
=== `_tier` field

When performing queries across multiple indexes, it is sometimes desirable to
target indexes held on nodes of a given data tier (`data_hot`, `data_warm`, `data_cold` or `data_frozen`).
The `_tier` field allows matching on the `tier_preference` setting of the index a document was indexed into.
The preferred value is accessible in certain queries :

[source,console]
--------------------------
PUT index_1/_doc/1
{
"text": "Document in index 1"
}
PUT index_2/_doc/2?refresh=true
{
"text": "Document in index 2"
}
GET index_1,index_2/_search
{
"query": {
"terms": {
"_tier": ["data_hot", "data_warm"] <1>
}
}
}
--------------------------

<1> Querying on the `_tier` field


Typically a query will use a `terms` query to list the tiers of interest but you can use
the `_tier` field in any query that is rewritten to a `term` query, such as the
`match`, `query_string`, `term`, `terms`, or `simple_query_string` query, as well as `prefix`
and `wildcard` queries. However, it does not support `regexp` and `fuzzy`
queries.

The `tier_preference` setting of the index is a comma-delimited list of tier names
in order of preference i.e. the preferred tier for hosting an index is listed first followed
by potentially many fall-back options. Query matching only considers the first preference
(the first value of a list).

Original file line number Diff line number Diff line change
@@ -0,0 +1,88 @@
/*
* Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
* or more contributor license agreements. Licensed under the Elastic License
* 2.0; you may not use this file except in compliance with the Elastic License
* 2.0.
*/

package org.elasticsearch.xpack.cluster.routing.allocation.mapper;

import org.apache.lucene.search.MatchAllDocsQuery;
import org.apache.lucene.search.MatchNoDocsQuery;
import org.apache.lucene.search.Query;
import org.elasticsearch.common.Strings;
import org.elasticsearch.common.regex.Regex;
import org.elasticsearch.index.mapper.ConstantFieldType;
import org.elasticsearch.index.mapper.KeywordFieldMapper;
import org.elasticsearch.index.mapper.MetadataFieldMapper;
import org.elasticsearch.index.mapper.ValueFetcher;
import org.elasticsearch.index.query.SearchExecutionContext;
import org.elasticsearch.xpack.cluster.routing.allocation.DataTierAllocationDecider;

import java.util.Collections;

public class DataTierFieldMapper extends MetadataFieldMapper {

public static final String NAME = "_tier";

public static final String CONTENT_TYPE = "_tier";

public static final TypeParser PARSER = new FixedTypeParser(c -> new DataTierFieldMapper());

static final class DataTierFieldType extends ConstantFieldType {

static final DataTierFieldType INSTANCE = new DataTierFieldType();

private DataTierFieldType() {
super(NAME, Collections.emptyMap());
}

@Override
public String typeName() {
return CONTENT_TYPE;
}

@Override
public String familyTypeName() {
return KeywordFieldMapper.CONTENT_TYPE;
}

@Override
protected boolean matches(String pattern, boolean caseInsensitive, SearchExecutionContext context) {
if (caseInsensitive) {
pattern = Strings.toLowercaseAscii(pattern);
}
String tierPreference = DataTierAllocationDecider.INDEX_ROUTING_PREFER_SETTING.get(context.getIndexSettings().getSettings());
if (tierPreference == null) {
return false;
}
// Tier preference can be a comma-delimited list of tiers, ordered by preference
// It was decided we should only test the first of these potentially multiple preferences.
String firstPreference = tierPreference.split(",")[0].trim();
return Regex.simpleMatch(pattern, firstPreference);
}

@Override
public Query existsQuery(SearchExecutionContext context) {
String tierPreference = DataTierAllocationDecider.INDEX_ROUTING_PREFER_SETTING.get(context.getIndexSettings().getSettings());
if (tierPreference == null) {
return new MatchNoDocsQuery();
}
return new MatchAllDocsQuery();
}

@Override
public ValueFetcher valueFetcher(SearchExecutionContext context, String format) {
throw new UnsupportedOperationException("Cannot fetch values for internal field [" + name() + "].");
}
}

public DataTierFieldMapper() {
super(DataTierFieldType.INSTANCE);
}

@Override
protected String contentType() {
return CONTENT_TYPE;
}
}
Original file line number Diff line number Diff line change
Expand Up @@ -41,6 +41,7 @@
import org.elasticsearch.env.NodeEnvironment;
import org.elasticsearch.index.IndexSettings;
import org.elasticsearch.index.engine.EngineFactory;
import org.elasticsearch.index.mapper.MetadataFieldMapper;
import org.elasticsearch.index.shard.IndexSettingProvider;
import org.elasticsearch.indices.recovery.RecoverySettings;
import org.elasticsearch.license.LicenseService;
Expand All @@ -51,6 +52,7 @@
import org.elasticsearch.plugins.ClusterPlugin;
import org.elasticsearch.plugins.EnginePlugin;
import org.elasticsearch.plugins.ExtensiblePlugin;
import org.elasticsearch.plugins.MapperPlugin;
import org.elasticsearch.plugins.RepositoryPlugin;
import org.elasticsearch.repositories.RepositoriesService;
import org.elasticsearch.repositories.Repository;
Expand All @@ -61,6 +63,7 @@
import org.elasticsearch.threadpool.ThreadPool;
import org.elasticsearch.watcher.ResourceWatcherService;
import org.elasticsearch.xpack.cluster.routing.allocation.DataTierAllocationDecider;
import org.elasticsearch.xpack.cluster.routing.allocation.mapper.DataTierFieldMapper;
import org.elasticsearch.xpack.core.action.ReloadAnalyzerAction;
import org.elasticsearch.xpack.core.action.TransportReloadAnalyzersAction;
import org.elasticsearch.xpack.core.action.TransportXPackInfoAction;
Expand Down Expand Up @@ -96,7 +99,13 @@
import java.util.stream.Collectors;
import java.util.stream.StreamSupport;

public class XPackPlugin extends XPackClientPlugin implements ExtensiblePlugin, RepositoryPlugin, EnginePlugin, ClusterPlugin {
public class XPackPlugin extends XPackClientPlugin
implements
ExtensiblePlugin,
RepositoryPlugin,
EnginePlugin,
ClusterPlugin,
MapperPlugin {
private static final DeprecationLogger deprecationLogger = DeprecationLogger.getLogger(XPackPlugin.class);

public static final String ASYNC_RESULTS_INDEX = ".async-search";
Expand Down Expand Up @@ -237,6 +246,12 @@ private static boolean alreadyContainsXPackCustomMetadata(ClusterState clusterSt
metadata.custom(WatcherMetadata.TYPE) != null ||
clusterState.custom(TokenMetadata.TYPE) != null;
}

@Override
public Map<String, MetadataFieldMapper.TypeParser> getMetadataMappers() {
return Map.of(DataTierFieldMapper.NAME, DataTierFieldMapper.PARSER);
}


@Override
public Settings additionalSettings() {
Expand Down
Original file line number Diff line number Diff line change
@@ -0,0 +1,105 @@
/*
* Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
* or more contributor license agreements. Licensed under the Elastic License
* 2.0; you may not use this file except in compliance with the Elastic License
* 2.0.
*/

package org.elasticsearch.xpack.cluster.routing.allocation.mapper;

import org.apache.lucene.search.MatchAllDocsQuery;
import org.apache.lucene.search.MatchNoDocsQuery;
import org.elasticsearch.Version;
import org.elasticsearch.cluster.metadata.IndexMetadata;
import org.elasticsearch.common.regex.Regex;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.index.IndexSettings;
import org.elasticsearch.index.mapper.MappedFieldType;
import org.elasticsearch.index.mapper.MapperServiceTestCase;
import org.elasticsearch.index.query.QueryShardException;
import org.elasticsearch.index.query.SearchExecutionContext;
import org.elasticsearch.xpack.cluster.routing.allocation.DataTierAllocationDecider;

import java.io.IOException;
import java.util.Arrays;
import java.util.function.Predicate;

import static java.util.Collections.emptyMap;
import static org.hamcrest.Matchers.containsString;

public class DataTierFieldTypeTests extends MapperServiceTestCase {

public void testPrefixQuery() throws IOException {
MappedFieldType ft = DataTierFieldMapper.DataTierFieldType.INSTANCE;
assertEquals(new MatchAllDocsQuery(), ft.prefixQuery("data_w", null, createContext()));
assertEquals(new MatchNoDocsQuery(), ft.prefixQuery("noSuchRole", null, createContext()));
}

public void testWildcardQuery() {
MappedFieldType ft = DataTierFieldMapper.DataTierFieldType.INSTANCE;
assertEquals(new MatchAllDocsQuery(), ft.wildcardQuery("data_w*", null, createContext()));
assertEquals(new MatchAllDocsQuery(), ft.wildcardQuery("data_warm", null, createContext()));
assertEquals(new MatchAllDocsQuery(), ft.wildcardQuery("Data_Warm", null, true, createContext()));
assertEquals(new MatchNoDocsQuery(), ft.wildcardQuery("Data_Warm", null, false, createContext()));
assertEquals(new MatchNoDocsQuery(), ft.wildcardQuery("noSuchRole", null, createContext()));
}

public void testTermQuery() {
MappedFieldType ft = DataTierFieldMapper.DataTierFieldType.INSTANCE;
assertEquals(new MatchAllDocsQuery(), ft.termQuery("data_warm", createContext()));
assertEquals(new MatchNoDocsQuery(), ft.termQuery("data_hot", createContext()));
assertEquals(new MatchNoDocsQuery(), ft.termQuery("noSuchRole", createContext()));
}

public void testTermsQuery() {
MappedFieldType ft = DataTierFieldMapper.DataTierFieldType.INSTANCE;
assertEquals(new MatchAllDocsQuery(), ft.termsQuery(Arrays.asList("data_warm"), createContext()));
assertEquals(new MatchNoDocsQuery(), ft.termsQuery(Arrays.asList("data_cold", "data_frozen"), createContext()));
}

public void testRegexpQuery() {
MappedFieldType ft = DataTierFieldMapper.DataTierFieldType.INSTANCE;
QueryShardException e = expectThrows(
QueryShardException.class,
() -> assertEquals(new MatchAllDocsQuery(), ft.regexpQuery("ind.x", 0, 0, 10, null, createContext()))
);
assertThat(e.getMessage(), containsString("Can only use regexp queries on keyword and text fields"));
}

private SearchExecutionContext createContext() {
IndexMetadata indexMetadata = IndexMetadata.builder("index")
.settings(
Settings.builder()
.put(IndexMetadata.SETTING_VERSION_CREATED, Version.CURRENT)
// Tier can be an ordered list of preferences - starting with primary and followed by fallbacks.
.put(DataTierAllocationDecider.INDEX_ROUTING_PREFER, "data_warm,data_hot")
)
.numberOfShards(1)
.numberOfReplicas(0)
.build();
IndexSettings indexSettings = new IndexSettings(indexMetadata, Settings.EMPTY);

Predicate<String> indexNameMatcher = pattern -> Regex.simpleMatch(pattern, "index");
return new SearchExecutionContext(
0,
0,
indexSettings,
null,
null,
null,
null,
null,
null,
xContentRegistry(),
writableRegistry(),
null,
null,
System::currentTimeMillis,
null,
indexNameMatcher,
() -> true,
null,
emptyMap()
);
}
}

0 comments on commit 08a188d

Please sign in to comment.