telegraf/plugins/processors/strings/strings.go

200 lines
4.3 KiB
Go

package strings
import (
"strings"
"unicode"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/plugins/processors"
)
type Strings struct {
Lowercase []converter `toml:"lowercase"`
Uppercase []converter `toml:"uppercase"`
Trim []converter `toml:"trim"`
TrimLeft []converter `toml:"trim_left"`
TrimRight []converter `toml:"trim_right"`
TrimPrefix []converter `toml:"trim_prefix"`
TrimSuffix []converter `toml:"trim_suffix"`
converters []converter
init bool
}
type ConvertFunc func(s string) string
type converter struct {
Field string
Tag string
Measurement string
Dest string
Cutset string
Suffix string
Prefix string
fn ConvertFunc
}
const sampleConfig = `
## Convert a tag value to uppercase
# [[processors.strings.uppercase]]
# tag = "method"
## Convert a field value to lowercase and store in a new field
# [[processors.strings.lowercase]]
# field = "uri_stem"
# dest = "uri_stem_normalised"
## Trim leading and trailing whitespace using the default cutset
# [[processors.strings.trim]]
# field = "message"
## Trim leading characters in cutset
# [[processors.strings.trim_left]]
# field = "message"
# cutset = "\t"
## Trim trailing characters in cutset
# [[processors.strings.trim_right]]
# field = "message"
# cutset = "\r\n"
## Trim the given prefix from the field
# [[processors.strings.trim_prefix]]
# field = "my_value"
# prefix = "my_"
## Trim the given suffix from the field
# [[processors.strings.trim_suffix]]
# field = "read_count"
# suffix = "_count"
`
func (s *Strings) SampleConfig() string {
return sampleConfig
}
func (s *Strings) Description() string {
return "Perform string processing on tags, fields, and measurements"
}
func (c *converter) convertTag(metric telegraf.Metric) {
tv, ok := metric.GetTag(c.Tag)
if !ok {
return
}
dest := c.Tag
if c.Dest != "" {
dest = c.Dest
}
metric.AddTag(dest, c.fn(tv))
}
func (c *converter) convertField(metric telegraf.Metric) {
fv, ok := metric.GetField(c.Field)
if !ok {
return
}
dest := c.Field
if c.Dest != "" {
dest = c.Dest
}
if fv, ok := fv.(string); ok {
metric.AddField(dest, c.fn(fv))
}
}
func (c *converter) convertMeasurement(metric telegraf.Metric) {
if metric.Name() != c.Measurement {
return
}
metric.SetName(c.fn(metric.Name()))
}
func (c *converter) convert(metric telegraf.Metric) {
if c.Field != "" {
c.convertField(metric)
}
if c.Tag != "" {
c.convertTag(metric)
}
if c.Measurement != "" {
c.convertMeasurement(metric)
}
}
func (s *Strings) initOnce() {
if s.init {
return
}
s.converters = make([]converter, 0)
for _, c := range s.Lowercase {
c.fn = strings.ToLower
s.converters = append(s.converters, c)
}
for _, c := range s.Uppercase {
c.fn = strings.ToUpper
s.converters = append(s.converters, c)
}
for _, c := range s.Trim {
if c.Cutset != "" {
c.fn = func(s string) string { return strings.Trim(s, c.Cutset) }
} else {
c.fn = func(s string) string { return strings.TrimFunc(s, unicode.IsSpace) }
}
s.converters = append(s.converters, c)
}
for _, c := range s.TrimLeft {
if c.Cutset != "" {
c.fn = func(s string) string { return strings.TrimLeft(s, c.Cutset) }
} else {
c.fn = func(s string) string { return strings.TrimLeftFunc(s, unicode.IsSpace) }
}
s.converters = append(s.converters, c)
}
for _, c := range s.TrimRight {
if c.Cutset != "" {
c.fn = func(s string) string { return strings.TrimRight(s, c.Cutset) }
} else {
c.fn = func(s string) string { return strings.TrimRightFunc(s, unicode.IsSpace) }
}
s.converters = append(s.converters, c)
}
for _, c := range s.TrimPrefix {
c.fn = func(s string) string { return strings.TrimPrefix(s, c.Prefix) }
s.converters = append(s.converters, c)
}
for _, c := range s.TrimSuffix {
c.fn = func(s string) string { return strings.TrimSuffix(s, c.Suffix) }
s.converters = append(s.converters, c)
}
s.init = true
}
func (s *Strings) Apply(in ...telegraf.Metric) []telegraf.Metric {
s.initOnce()
for _, metric := range in {
for _, converter := range s.converters {
converter.convert(metric)
}
}
return in
}
func init() {
processors.Add("strings", func() telegraf.Processor {
return &Strings{}
})
}