Reroute processor

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The reroute processor allows to route a document to another target index or data stream. It has two main modes:

When setting the destination option, the target is explicitly specified and the dataset and namespace options can’t be set.

When the destination option is not set, this processor is in a data stream mode. Note that in this mode, the reroute processor can only be used on data streams that follow the data stream naming scheme. Trying to use this processor on a data stream with a non-compliant name will raise an exception.

The name of a data stream consists of three parts: <type>-<dataset>-<namespace>. See the data stream naming scheme documentation for more details.

This processor can use both static values or reference fields from the document to determine the dataset and namespace components of the new target. See Table 39, “Reroute options” for more details.

It’s not possible to change the type of the data stream with the reroute processor.

After a reroute processor has been executed, all the other processors of the current pipeline are skipped, including the final pipeline. If the current pipeline is executed in the context of a Pipeline, the calling pipeline will be skipped, too. This means that at most one reroute processor is ever executed within a pipeline, allowing to define mutually exclusive routing conditions, similar to a if, else-if, else-if, … condition.

The reroute processor ensures that the data_stream.<type|dataset|namespace> fields are set according to the new target. If the document contains a event.dataset value, it will be updated to reflect the same value as data_stream.dataset.

Note that the client needs to have permissions to the final target. Otherwise, the document will be rejected with a security exception which looks like this:

{"type":"security_exception","reason":"action [indices:admin/auto_create] is unauthorized for API key id [8-dt9H8BqGblnY2uSI--] of user [elastic/fleet-server] on indices [logs-foo-default], this action is granted by the index privileges [auto_configure,create_index,manage,all]"}

Table 39. Reroute options

Name Required Default Description

destination

no

-

A static value for the target. Can’t be set when the dataset or namespace option is set.

dataset

no

{{data_stream.dataset}}

Field references or a static value for the dataset part of the data stream name. In addition to the criteria for index names, cannot contain - and must be no longer than 100 characters. Example values are nginx.access and nginx.error.

Supports field references with a mustache-like syntax (denoted as {{double}} or {{{triple}}} curly braces). When resolving field references, the processor replaces invalid characters with _. Uses the <dataset> part of the index name as a fallback if all field references resolve to a null, missing, or non-string value.

namespace

no

{{data_stream.namespace}}

Field references or a static value for the namespace part of the data stream name. See the criteria for index names for allowed characters. Must be no longer than 100 characters.

Supports field references with a mustache-like syntax (denoted as {{double}} or {{{triple}}} curly braces). When resolving field references, the processor replaces invalid characters with _. Uses the <namespace> part of the index name as a fallback if all field references resolve to a null, missing, or non-string value.

description

no

-

Description of the processor. Useful for describing the purpose of the processor or its configuration.

if

no

-

Conditionally execute the processor. See Conditionally run a processor.

ignore_failure

no

false

Ignore failures for the processor. See Handling pipeline failures.

on_failure

no

-

Handle failures for the processor. See Handling pipeline failures.

tag

no

-

Identifier for the processor. Useful for debugging and metrics.

The if option can be used to define the condition in which the document should be rerouted to a new target.

{
  "reroute": {
    "tag": "nginx",
    "if" : "ctx?.log?.file?.path?.contains('nginx')",
    "dataset": "nginx"
  }
}

The dataset and namespace options can contain either a single value or a list of values that are used as a fallback. If a field reference evaluates to null, is not present in the document, the next value or field reference is used. If a field reference evaluates to a non-String value, the processor fails.

In the following example, the processor would first try to resolve the value for the service.name field to determine the value for dataset. If that field resolves to null, is missing, or is a non-string value, it would try the next element in the list. In this case, this is the static value "generic". The namespace option is configured with just a single static value.

{
  "reroute": {
    "dataset": [
        "{{service.name}}",
        "generic"
    ],
    "namespace": "default"
  }
}