wms

Milestone: 3

This is a community-contributed plugin! It does not ship with logstash by default, but it is easy to install! To use this, you must have installed the contrib plugins package.

This filter allows to parse WMS (Web-Map Service) queries.

It can be used to extract the bounding box from the requests (in case of GetMap queries for example), and the usual parameters defined in the OGC WMS standard. See http://www.opengeospatial.org/standards/wms for more infos.

The list of expected parameter can be customized by giving a specific array of fields, but the default one should already fill in the logstash event with the most common information we can find in regular WMS queries (service, version, layers, requested projection, output format …).

The module also permits to reproject the bounding boxes from getmap requests, using the GeoScript (Gem / Wrapper to the Geotools java library).

It can be customized using the following parameters:

  • output_epsg: the output projection to be used when setting the x/y coordinates, default to regular lat/long wgs84 (‘epsg:4326’)
  • wms_fields: The fields that have to be potentially extracted from the query
  • prefix: the string that will be used to prefix the variables added to the logstash event, defaults to ‘wms.’

Synopsis

This is what it might look like in your config file:
filter {
  wms {
    add_field => ... # hash (optional), default: {}
    add_tag => ... # array (optional), default: []
    output_epsg => ... # string (optional), default: "epsg:4326"
    prefix => ... # string (optional), default: "wms."
    remove_field => ... # array (optional), default: []
    remove_tag => ... # array (optional), default: []
    wms_fields => ... # array (optional), default: ["service", "version", "request", "layers", "styles", "crs", "srs", "bbox", "width", "height", "format", "transparent", "bgcolor", "bgcolor", "exceptions", "time", "elevation", "wfs"]
  }
}

Details

add_field

  • Value type is hash
  • Default value is {}

If this filter is successful, add any arbitrary fields to this event. Field names can be dynamic and include parts of the event using the %{field} Example:

filter {
  wms {
    add_field => { "foo_%{somefield}" => "Hello world, from %{host}" }
  }
}

# You can also add multiple fields at once:

filter {
  wms {
    add_field => { 
      "foo_%{somefield}" => "Hello world, from %{host}"
      "new_field" => "new_static_value"
    }
  }
}

If the event has field “somefield” == “hello” this filter, on success, would add field “foo_hello” if it is present, with the value above and the %{host} piece replaced with that value from the event. The second example would also add a hardcoded field.

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 {
  wms {
    add_tag => [ "foo_%{somefield}" ]
  }
}

# You can also add multiple tags at once:
filter {
  wms {
    add_tag => [ "foo_%{somefield}", "taggedy_tag"]
  }
}

If the event has field “somefield” == “hello” this filter, on success, would add a tag “foo_hello” (and the second example would of course add a “taggedy_tag” tag).

exclude_tags DEPRECATED

  • DEPRECATED WARNING: This config item is deprecated. It may be removed in a further version.
  • Value type is array
  • Default value is []

Only handle events without all/any (controlled by exclude_any config option) of these tags. Optional.

output_epsg

  • Value type is string
  • Default value is "epsg:4326"

epsg for the output

prefix

  • Value type is string
  • Default value is "wms."

prefix for parsed elements added by the plugin

remove_field

  • Value type is array
  • Default value is []

If this filter is successful, remove arbitrary fields from this event. Fields names can be dynamic and include parts of the event using the %{field} Example:

filter {
  wms {
    remove_field => [ "foo_%{somefield}" ]
  }
}

# You can also remove multiple fields at once:

filter {
  wms {
    remove_field => [ "foo_%{somefield}" "my_extraneous_field" ]
  }
}

If the event has field “somefield” == “hello” this filter, on success, would remove the field with name “foo_hello” if it is present. The second example would remove an additional, non-dynamic field.

remove_tag

  • Value type is array
  • Default value is []

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

filter {
  wms {
    remove_tag => [ "foo_%{somefield}" ]
  }
}

# You can also remove multiple tags at once:

filter {
  wms {
    remove_tag => [ "foo_%{somefield}", "sad_unwanted_tag"]
  }
}

If the event has field “somefield” == “hello” this filter, on success, would remove the tag “foo_hello” if it is present. The second example would remove a sad, unwanted tag as well.

tags DEPRECATED

  • DEPRECATED WARNING: This config item is deprecated. It may be removed in a further version.
  • Value type is array
  • Default value is []

Only handle events with all/any (controlled by include_any config option) of these tags. Optional.

type DEPRECATED

  • DEPRECATED WARNING: This config item is deprecated. It may be removed in a further version.
  • Value type is string
  • Default value is ""

Note that all of the specified routing options (type,tags.exclude_tags,include_fields,exclude_fields) must be met in order for the event to be handled by the filter. 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.

wms_fields

  • Value type is array
  • Default value is ["service", "version", "request", "layers", "styles", "crs", "srs", "bbox", "width", "height", "format", "transparent", "bgcolor", "bgcolor", "exceptions", "time", "elevation", "wfs"]

default wms parameters to extract


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