json

Status: beta

JSON filter. Takes a field that contains JSON and expands it into an actual datastructure.

Synopsis

This is what it might look like in your config file:

filter {
  json {
    /[A-Za-z0-9_-]+/ => ... # string (optional)
    add_field => ... # hash (optional), default: {}
    add_tag => ... # array (optional), default: []
    tags => ... # array (optional), default: []
    type => ... # string (optional), default: ""
  }
}

Details

/[A-Za-z0-9_-]+/

• The configuration attribute name here is anything that matches the above regular expression.
• Value type is string
• There is no default value for this setting.

Config for json is: source: dest JSON in the value of the source field will be expanded into a datastructure in the "dest" field. Note: if the "dest" field already exists, it will be overridden.

add_field

• Value type is hash
• Default value is {}

If this filter is successful, add any arbitrary fields to this event. Example:

filter {
  myfilter {
    add_field => [ "sample", "Hello world, from %{@source}" ]
  }
}

On success, myfilter will then add field 'sample' with the value above and the %{@source} piece replaced with that value from the event.

add_tag

• Value type is array
• Default value is []

If this filter is successful, add arbitrary tags to the event. Tags can be dynamic and include parts of the event using the %{field} syntax. Example:

filter {
  myfilter {
    add_tag => [ "foo_%{somefield}" ]
  }
}

If the event has field "somefield" == "hello" this filter, on success, would add a tag "foo_hello"

tags

• Value type is array
• Default value is []

Only handle events with all of these tags. Note that if you specify a type, the event must also match that type. Optional.

type

• Value type is string
• Default value is ""

The type to act on. If a type is given, then this filter will only act on messages with the same type. See any input plugin's "type" attribute for more. Optional.

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This is documentation from lib/logstash/filters/json.rb