The template
processor applies a Go template to metrics to generate a new
tag. The primary use case of this plugin is to create a tag that can be used
for dynamic routing to multiple output plugins or using an output specific
routing option.
The template has access to each metric's measurement name, tags, fields, and
timestamp using the interface in /template_metric.go
.
Read the full Go Template Documentation.
In addition to the plugin-specific configuration settings, plugins support additional global and plugin configuration settings. These settings are used to modify metrics, tags, and field or create aliases and configure ordering, etc. See the CONFIGURATION.md for more details.
# Uses a Go template to create a new tag
[[processors.template]]
## Go template used to create the tag name of the output. In order to
## ease TOML escaping requirements, you should use single quotes around
## the template string.
tag = "topic"
## Go template used to create the tag value of the output. In order to
## ease TOML escaping requirements, you should use single quotes around
## the template string.
template = '{{ .Tag "hostname" }}.{{ .Tag "level" }}'
[[processors.template]]
tag = "topic"
template = '{{ .Tag "hostname" }}.{{ .Tag "level" }}'
- cpu,level=debug,hostname=localhost time_idle=42
+ cpu,level=debug,hostname=localhost,topic=localhost.debug time_idle=42
[[processors.template]]
tag = '{{ .Field "type" }}'
template = '{{ .Name }}'
- cpu,level=debug,hostname=localhost time_idle=42,type=sensor
+ cpu,level=debug,hostname=localhost,sensor=cpu time_idle=42,type=sensor
[[processors.template]]
tag = "measurement"
template = '{{ .Name }}'
- cpu,hostname=localhost time_idle=42
+ cpu,hostname=localhost,measurement=cpu time_idle=42
[[processors.template]]
tag = "year"
template = '{{.Time.UTC.Year}}'
Sometimes it is useful to pass all fields with their values into a single
message for sending it to a monitoring system (e.g. Syslog, GroundWork), then
you can use .Fields
or .Tags
:
[[processors.template]]
tag = "message"
template = 'Message about {{.Name}} fields: {{.Fields}}'
- cpu,hostname=localhost time_idle=42
+ cpu,hostname=localhost,message=Message\ about\ cpu\ fields:\ map[time_idle:42] time_idle=42
More advanced example, which might make more sense:
[[processors.template]]
tag = "message"
template = '''Message about {{.Name}} fields:
{{ range $field, $value := .Fields -}}
{{$field}}:{{$value}}
{{ end }}'''
- cpu,hostname=localhost time_idle=42
+ cpu,hostname=localhost,message=Message\ about\ cpu\ fields:\ntime_idle:42\n time_idle=42
[[processors.template]]
tag = "metric"
template = '{{.}}'
- cpu,hostname=localhost time_idle=42
+ cpu,hostname=localhost,metric=cpu\ map[hostname:localhost]\ map[time_idle:42]\ 1257894000000000000 time_idle=42