Adds support for removing/keeping tags from metrics

closes #706

internal/models/filter.go

@@ -1,33 +1,104 @@
 package internal_models
 
 import (
+	"fmt"
 	"strings"
 
+	"github.com/gobwas/glob"
+
 	"github.com/influxdata/telegraf"
-	"github.com/influxdata/telegraf/internal"
 )
 
 // TagFilter is the name of a tag, and the values on which to filter
 type TagFilter struct {
 	Name   string
 	Filter []string
+	filter glob.Glob
 }
 
 // Filter containing drop/pass and tagdrop/tagpass rules
 type Filter struct {
 	NameDrop []string
+	nameDrop glob.Glob
 	NamePass []string
+	namePass glob.Glob
 
 	FieldDrop []string
+	fieldDrop glob.Glob
 	FieldPass []string
+	fieldPass glob.Glob
 
 	TagDrop []TagFilter
 	TagPass []TagFilter
 
+	TagExclude []string
+	tagExclude glob.Glob
+	TagInclude []string
+	tagInclude glob.Glob
+
 	IsActive bool
 }
 
-func (f Filter) ShouldMetricPass(metric telegraf.Metric) bool {
+// Compile all Filter lists into glob.Glob objects.
+func (f *Filter) CompileFilter() error {
+	var err error
+	f.nameDrop, err = compileFilter(f.NameDrop)
+	if err != nil {
+		return fmt.Errorf("Error compiling 'namedrop', %s", err)
+	}
+	f.namePass, err = compileFilter(f.NamePass)
+	if err != nil {
+		return fmt.Errorf("Error compiling 'namepass', %s", err)
+	}
+
+	f.fieldDrop, err = compileFilter(f.FieldDrop)
+	if err != nil {
+		return fmt.Errorf("Error compiling 'fielddrop', %s", err)
+	}
+	f.fieldPass, err = compileFilter(f.FieldPass)
+	if err != nil {
+		return fmt.Errorf("Error compiling 'fieldpass', %s", err)
+	}
+
+	f.tagExclude, err = compileFilter(f.TagExclude)
+	if err != nil {
+		return fmt.Errorf("Error compiling 'tagexclude', %s", err)
+	}
+	f.tagInclude, err = compileFilter(f.TagInclude)
+	if err != nil {
+		return fmt.Errorf("Error compiling 'taginclude', %s", err)
+	}
+
+	for i, _ := range f.TagDrop {
+		f.TagDrop[i].filter, err = compileFilter(f.TagDrop[i].Filter)
+		if err != nil {
+			return fmt.Errorf("Error compiling 'tagdrop', %s", err)
+		}
+	}
+	for i, _ := range f.TagPass {
+		f.TagPass[i].filter, err = compileFilter(f.TagPass[i].Filter)
+		if err != nil {
+			return fmt.Errorf("Error compiling 'tagpass', %s", err)
+		}
+	}
+	return nil
+}
+
+func compileFilter(filter []string) (glob.Glob, error) {
+	if len(filter) == 0 {
+		return nil, nil
+	}
+	var g glob.Glob
+	var err error
+	if len(filter) == 1 {
+		g, err = glob.Compile(filter[0])
+	} else {
+		g, err = glob.Compile("{" + strings.Join(filter, ",") + "}")
+	}
+	return g, err
+}
+
+func (f *Filter) ShouldMetricPass(metric telegraf.Metric) bool {
 	if f.ShouldNamePass(metric.Name()) && f.ShouldTagsPass(metric.Tags()) {
 		return true
 	}
@@ -36,70 +107,51 @@ func (f Filter) ShouldMetricPass(metric telegraf.Metric) bool {
 
 // ShouldFieldsPass returns true if the metric should pass, false if should drop
 // based on the drop/pass filter parameters
-func (f Filter) ShouldNamePass(key string) bool {
-	if f.NamePass != nil {
-		for _, pat := range f.NamePass {
-			// TODO remove HasPrefix check, leaving it for now for legacy support.
-			// Cam, 2015-12-07
-			if strings.HasPrefix(key, pat) || internal.Glob(pat, key) {
-				return true
-			}
+func (f *Filter) ShouldNamePass(key string) bool {
+	if f.namePass != nil {
+		if f.namePass.Match(key) {
+			return true
 		}
 		return false
 	}
 
-	if f.NameDrop != nil {
-		for _, pat := range f.NameDrop {
-			// TODO remove HasPrefix check, leaving it for now for legacy support.
-			// Cam, 2015-12-07
-			if strings.HasPrefix(key, pat) || internal.Glob(pat, key) {
-				return false
-			}
+	if f.nameDrop != nil {
+		if f.nameDrop.Match(key) {
+			return false
 		}
-
-		return true
 	}
 	return true
 }
 
 // ShouldFieldsPass returns true if the metric should pass, false if should drop
 // based on the drop/pass filter parameters
-func (f Filter) ShouldFieldsPass(key string) bool {
-	if f.FieldPass != nil {
-		for _, pat := range f.FieldPass {
-			// TODO remove HasPrefix check, leaving it for now for legacy support.
-			// Cam, 2015-12-07
-			if strings.HasPrefix(key, pat) || internal.Glob(pat, key) {
-				return true
-			}
+func (f *Filter) ShouldFieldsPass(key string) bool {
+	if f.fieldPass != nil {
+		if f.fieldPass.Match(key) {
+			return true
 		}
 		return false
 	}
 
-	if f.FieldDrop != nil {
-		for _, pat := range f.FieldDrop {
-			// TODO remove HasPrefix check, leaving it for now for legacy support.
-			// Cam, 2015-12-07
-			if strings.HasPrefix(key, pat) || internal.Glob(pat, key) {
-				return false
-			}
+	if f.fieldDrop != nil {
+		if f.fieldDrop.Match(key) {
+			return false
 		}
-
-		return true
 	}
 	return true
 }
 
 // ShouldTagsPass returns true if the metric should pass, false if should drop
 // based on the tagdrop/tagpass filter parameters
-func (f Filter) ShouldTagsPass(tags map[string]string) bool {
+func (f *Filter) ShouldTagsPass(tags map[string]string) bool {
 	if f.TagPass != nil {
 		for _, pat := range f.TagPass {
+			if pat.filter == nil {
+				continue
+			}
 			if tagval, ok := tags[pat.Name]; ok {
-				for _, filter := range pat.Filter {
-					if internal.Glob(filter, tagval) {
-						return true
-					}
+				if pat.filter.Match(tagval) {
+					return true
 				}
 			}
 		}
@@ -108,11 +160,12 @@ func (f Filter) ShouldTagsPass(tags map[string]string) bool {
 
 	if f.TagDrop != nil {
 		for _, pat := range f.TagDrop {
+			if pat.filter == nil {
+				continue
+			}
 			if tagval, ok := tags[pat.Name]; ok {
-				for _, filter := range pat.Filter {
-					if internal.Glob(filter, tagval) {
-						return false
-					}
+				if pat.filter.Match(tagval) {
+					return false
 				}
 			}
 		}
@@ -121,3 +174,23 @@ func (f Filter) ShouldTagsPass(tags map[string]string) bool {
 
 	return true
 }
+
+// Apply TagInclude and TagExclude filters.
+// modifies the tags map in-place.
+func (f *Filter) FilterTags(tags map[string]string) {
+	if f.tagInclude != nil {
+		for k, _ := range tags {
+			if !f.tagInclude.Match(k) {
+				delete(tags, k)
+			}
+		}
+	}
+
+	if f.tagExclude != nil {
+		for k, _ := range tags {
+			if f.tagExclude.Match(k) {
+				delete(tags, k)
+			}
+		}
+	}
+}