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( "Client@cbElasticsearch" )
.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( "Client@cbElasticsearch" )
.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( "Client@cbElasticsearch" )
.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( "Client@cbElasticsearch" )
.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( "Client@cbElasticsearch" )
.reindex(
// ...
script = {
"lang" : "painless",
"source" : getInstance( "Util@cbElasticsearch" )
.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( "Client@cbElasticsearch" )
.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 5mo ago