Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

backport of: add is-write-index flag to aliases (#30942) #31412

Merged
merged 2 commits into from
Jun 20, 2018
Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
88 changes: 88 additions & 0 deletions docs/reference/indices/aliases.asciidoc
Original file line number Diff line number Diff line change
Expand Up @@ -244,6 +244,94 @@ GET /alias2/_search?q=user:kimchy&routing=2,3
// CONSOLE
// TEST[continued]

[float]
[[aliases-write-index]]
==== Write Index

It is possible to associate the index pointed to by an alias as the write index.
When specified, all index and update requests against an alias that point to multiple
indices will attempt to resolve to the one index that is the write index.
Only one index per alias can be assigned to be the write index at a time. If no write index is specified
and there are multiple indices referenced by an alias, then writes will not be allowed.

It is possible to specify an index associated with an alias as a write index using both the aliases API
and index creation API.

[source,js]
--------------------------------------------------
POST /_aliases
{
"actions" : [
{
"add" : {
"index" : "test",
"alias" : "alias1",
"is_write_index" : true
}
}
]
}
--------------------------------------------------
// CONSOLE
// TEST[s/^/PUT test\n/]

In this example, we associate the alias `alias1` to both `test` and `test2`, where
`test` will be the index chosen for writing to.

[source,js]
--------------------------------------------------
PUT /alias1/_doc/1
{
"foo": "bar"
}
--------------------------------------------------
// CONSOLE
// TEST[continued]

The new document that was indexed to `/alias1/_doc/1` will be indexed as if it were
`/test/_doc/1`.

[source,js]
--------------------------------------------------
GET /test/_doc/1
--------------------------------------------------
// CONSOLE
// TEST[continued]

To swap which index is the write index for an alias, the Aliases API can be leveraged to
do an atomic swap. The swap is not dependent on the ordering of the actions.

[source,js]
--------------------------------------------------
POST /_aliases
{
"actions" : [
{
"add" : {
"index" : "test",
"alias" : "alias1",
"is_write_index" : true
}
}, {
"add" : {
"index" : "test2",
"alias" : "alias1",
"is_write_index" : false
}
}
]
}
--------------------------------------------------
// CONSOLE
// TEST[s/^/PUT test\nPUT test2\n/]

[IMPORTANT]
=====================================
Aliases that do not explicitly set `is_write_index: true` for an index, and
only reference one index, will have that referenced index behave as if it is the write index
until an additional index is referenced. At that point, there will be no write index and
writes will be rejected.
=====================================

[float]
[[alias-adding]]
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -82,14 +82,37 @@
indices.get_alias:
index: test_index

- match: {test_index.aliases.test_alias: {}}
- match: {test_index.aliases.test_blias.search_routing: b}
- match: {test_index.aliases.test_blias.index_routing: b}
- is_false: test_index.aliases.test_blias.filter
- match: {test_index.aliases.test_clias.filter.term.field: value}
- is_false: test_index.aliases.test_clias.index_routing
- is_false: test_index.aliases.test_clias.search_routing

---
"Create index with write aliases":
- skip:
version: " - 6.99.99"
reason: is_write_index is not implemented in ES <= 6.x
- do:
indices.create:
index: test_index
body:
aliases:
test_alias: {}
test_blias:
is_write_index: false
test_clias:
is_write_index: true

- do:
indices.get_alias:
index: test_index

- is_false: test_index.aliases.test_alias.is_write_index
- is_false: test_index.aliases.test_blias.is_write_index
- is_true: test_index.aliases.test_clias.is_write_index

---
"Create index with no type mappings":
- do:
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -20,6 +20,7 @@
package org.elasticsearch.action.admin.indices.alias;

import org.elasticsearch.ElasticsearchGenerationException;
import org.elasticsearch.Version;
import org.elasticsearch.common.Nullable;
import org.elasticsearch.common.ParseField;
import org.elasticsearch.common.Strings;
Expand Down Expand Up @@ -49,6 +50,7 @@ public class Alias implements Streamable, ToXContentFragment {
private static final ParseField ROUTING = new ParseField("routing");
private static final ParseField INDEX_ROUTING = new ParseField("index_routing", "indexRouting", "index-routing");
private static final ParseField SEARCH_ROUTING = new ParseField("search_routing", "searchRouting", "search-routing");
private static final ParseField IS_WRITE_INDEX = new ParseField("is_write_index");

private String name;

Expand All @@ -61,6 +63,9 @@ public class Alias implements Streamable, ToXContentFragment {
@Nullable
private String searchRouting;

@Nullable
private Boolean writeIndex;

private Alias() {

}
Expand Down Expand Up @@ -167,6 +172,21 @@ public Alias searchRouting(String searchRouting) {
return this;
}

/**
* @return the write index flag for the alias
*/
public Boolean writeIndex() {
return writeIndex;
}

/**
* Sets whether an alias is pointing to a write-index
*/
public Alias writeIndex(@Nullable Boolean writeIndex) {
this.writeIndex = writeIndex;
return this;
}

/**
* Allows to read an alias from the provided input stream
*/
Expand All @@ -182,6 +202,11 @@ public void readFrom(StreamInput in) throws IOException {
filter = in.readOptionalString();
indexRouting = in.readOptionalString();
searchRouting = in.readOptionalString();
if (in.getVersion().onOrAfter(Version.V_6_4_0)) {
writeIndex = in.readOptionalBoolean();
} else {
writeIndex = null;
}
}

@Override
Expand All @@ -190,6 +215,9 @@ public void writeTo(StreamOutput out) throws IOException {
out.writeOptionalString(filter);
out.writeOptionalString(indexRouting);
out.writeOptionalString(searchRouting);
if (out.getVersion().onOrAfter(Version.V_6_4_0)) {
out.writeOptionalBoolean(writeIndex);
}
}

/**
Expand Down Expand Up @@ -219,6 +247,10 @@ public static Alias fromXContent(XContentParser parser) throws IOException {
} else if (SEARCH_ROUTING.match(currentFieldName, parser.getDeprecationHandler())) {
alias.searchRouting(parser.text());
}
} else if (token == XContentParser.Token.VALUE_BOOLEAN) {
if (IS_WRITE_INDEX.match(currentFieldName, parser.getDeprecationHandler())) {
alias.writeIndex(parser.booleanValue());
}
}
}
return alias;
Expand All @@ -245,6 +277,8 @@ public XContentBuilder toXContent(XContentBuilder builder, Params params) throws
}
}

builder.field(IS_WRITE_INDEX.getPreferredName(), writeIndex);

builder.endObject();
return builder;
}
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -20,6 +20,7 @@
package org.elasticsearch.action.admin.indices.alias;

import org.elasticsearch.ElasticsearchGenerationException;
import org.elasticsearch.Version;
import org.elasticsearch.action.ActionRequestValidationException;
import org.elasticsearch.action.AliasesRequest;
import org.elasticsearch.action.support.IndicesOptions;
Expand Down Expand Up @@ -84,6 +85,7 @@ public static class AliasActions implements AliasesRequest, Writeable, ToXConten
private static final ParseField ROUTING = new ParseField("routing");
private static final ParseField INDEX_ROUTING = new ParseField("index_routing", "indexRouting", "index-routing");
private static final ParseField SEARCH_ROUTING = new ParseField("search_routing", "searchRouting", "search-routing");
private static final ParseField IS_WRITE_INDEX = new ParseField("is_write_index");

private static final ParseField ADD = new ParseField("add");
private static final ParseField REMOVE = new ParseField("remove");
Expand Down Expand Up @@ -179,6 +181,7 @@ private static ObjectParser<AliasActions, Void> parser(String name, Supplier<Ali
ADD_PARSER.declareField(AliasActions::routing, XContentParser::text, ROUTING, ValueType.INT);
ADD_PARSER.declareField(AliasActions::indexRouting, XContentParser::text, INDEX_ROUTING, ValueType.INT);
ADD_PARSER.declareField(AliasActions::searchRouting, XContentParser::text, SEARCH_ROUTING, ValueType.INT);
ADD_PARSER.declareField(AliasActions::writeIndex, XContentParser::booleanValue, IS_WRITE_INDEX, ValueType.BOOLEAN);
}
private static final ObjectParser<AliasActions, Void> REMOVE_PARSER = parser(REMOVE.getPreferredName(), AliasActions::remove);
private static final ObjectParser<AliasActions, Void> REMOVE_INDEX_PARSER = parser(REMOVE_INDEX.getPreferredName(),
Expand Down Expand Up @@ -215,6 +218,7 @@ private static ObjectParser<AliasActions, Void> parser(String name, Supplier<Ali
private String routing;
private String indexRouting;
private String searchRouting;
private Boolean writeIndex;

public AliasActions(AliasActions.Type type) {
this.type = type;
Expand All @@ -231,6 +235,9 @@ public AliasActions(StreamInput in) throws IOException {
routing = in.readOptionalString();
searchRouting = in.readOptionalString();
indexRouting = in.readOptionalString();
if (in.getVersion().onOrAfter(Version.V_6_4_0)) {
writeIndex = in.readOptionalBoolean();
}
}

@Override
Expand All @@ -242,6 +249,9 @@ public void writeTo(StreamOutput out) throws IOException {
out.writeOptionalString(routing);
out.writeOptionalString(searchRouting);
out.writeOptionalString(indexRouting);
if (out.getVersion().onOrAfter(Version.V_6_4_0)) {
out.writeOptionalBoolean(writeIndex);
}
}

/**
Expand Down Expand Up @@ -401,6 +411,18 @@ public AliasActions filter(QueryBuilder filter) {
}
}

public AliasActions writeIndex(Boolean writeIndex) {
if (type != AliasActions.Type.ADD) {
throw new IllegalArgumentException("[is_write_index] is unsupported for [" + type + "]");
}
this.writeIndex = writeIndex;
return this;
}

public Boolean writeIndex() {
return writeIndex;
}

@Override
public String[] aliases() {
return aliases;
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -130,6 +130,18 @@ public IndicesAliasesRequestBuilder addAlias(String index, String alias, QueryBu
return this;
}

/**
* Adds an alias to the index.
*
* @param index The index
* @param alias The alias
* @param writeIndex write index flag
*/
public IndicesAliasesRequestBuilder addAlias(String index, String alias, boolean writeIndex) {
request.addAliasAction(AliasActions.add().index(index).alias(alias).writeIndex(writeIndex));
return this;
}

/**
* Removes an alias from the index.
*
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -100,7 +100,8 @@ protected void masterOperation(final IndicesAliasesRequest request, final Cluste
switch (action.actionType()) {
case ADD:
for (String alias : concreteAliases(action, state.metaData(), index)) {
finalActions.add(new AliasAction.Add(index, alias, action.filter(), action.indexRouting(), action.searchRouting()));
finalActions.add(new AliasAction.Add(index, alias, action.filter(), action.indexRouting(),
action.searchRouting(), action.writeIndex()));
}
break;
case REMOVE:
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -173,7 +173,7 @@ public void onFailure(Exception e) {
static IndicesAliasesClusterStateUpdateRequest prepareRolloverAliasesUpdateRequest(String oldIndex, String newIndex,
RolloverRequest request) {
List<AliasAction> actions = unmodifiableList(Arrays.asList(
new AliasAction.Add(newIndex, request.getAlias(), null, null, null),
new AliasAction.Add(newIndex, request.getAlias(), null, null, null, null),
new AliasAction.Remove(oldIndex, request.getAlias())));
final IndicesAliasesClusterStateUpdateRequest updateRequest = new IndicesAliasesClusterStateUpdateRequest(actions)
.ackTimeout(request.ackTimeout())
Expand Down
Loading