Reindexing
Sometimes indices get messy. Learn how to reindex your data in CBElasticsearch.
On occasion, due to a mapping or settings change, you will need to reindex data from one index (the "source") to another (the "destination"). You can do this by calling the
reindex
method on CBElasticsearch's Client
component.getInstance( "[email protected]" )
.reindex( "oldIndex", "newIndex" );
If you want the work to be done asynchronusly, you can pass
false
to the waitForCompletion
flag. When this flag is set to false the method will return a Task
instance, which can be used to follow up on the completion status of the reindex process.getInstance( "[email protected]" )
.reindex(
source = "oldIndex",
destination = "newIndex",
waitForCompletion = false
);
If you have more settings or constraints for the reindex action, you can pass a struct containing valid options to
source
and destination
.getInstance( "[email protected]" )
.reindex(
source = {
"index": "oldIndex",
"type": "testdocs",
"query": {
"term": {
"active": true
}
}
},
destination = "newIndex"
);
You may also pass a script in to the
reindex
method to transform objects as they are being transferred from one index to another:getInstance( "[email protected]" )
.reindex(
source = {
"index": "oldIndex",
"type": "testdocs",
"query": {
"term": {
"active": true
}
}
},
destination = "newIndex",
script = {
"lang" : "painless",
"source" : "if( ctx._source.foo != null && ctx._source.foo == 'baz' ){ ctx._source.foo = 'bar'; }"
}
);
Note that a Painless script containing newlines, tabs, or space indentation will throw a parsing error. To work around this limitation, use CBElasticsearch's
Util.formatToPainless( string script )
method to remove newlines and indentation:getInstance( "[email protected]" )
.reindex(
// ...
script = {
"lang" : "painless",
"source" : getInstance( "[email protected]" )
.formatToPainless( getReindexScript() )
}
);
If you
waitForCompletion
and the reindex action fails, a cbElasticsearch.HyperClient.ReindexFailedException
will be thrown. You can disable the exception by passing false
to the throwOnError
parameter:getInstance( "[email protected]" )
.reindex(
source = "oldIndex",
destination = "newIndex",
waitForCompletion = false,
throwOnError = false
);
As always, check out the Elasticsearch documentation for more specifics on what reindexing is and how it works.
Last modified 2mo ago