2 files changed, 249 insertions, 0 deletions

diff --git a/cli/internal/util/filter/filter.go b/cli/internal/util/filter/filter.go
new file mode 100644
index 0000000..fbc475d
--- /dev/null
+++ b/cli/internal/util/filter/filter.go
@@ -0,0 +1,133 @@
+// Copyright (c) 2015-2020 InfluxData Inc. MIT License (MIT)
+// https://github.com/influxdata/telegraf
+package filter
+
+import (
+	"strings"
+
+	"github.com/gobwas/glob"
+)
+
+type Filter interface {
+	Match(string) bool
+}
+
+// Compile takes a list of string filters and returns a Filter interface
+// for matching a given string against the filter list. The filter list
+// supports glob matching too, ie:
+//
+//	f, _ := Compile([]string{"cpu", "mem", "net*"})
+//	f.Match("cpu")     // true
+//	f.Match("network") // true
+//	f.Match("memory")  // false
+func Compile(filters []string) (Filter, error) {
+	// return if there is nothing to compile
+	if len(filters) == 0 {
+		return nil, nil
+	}
+
+	// check if we can compile a non-glob filter
+	noGlob := true
+	for _, filter := range filters {
+		if hasMeta(filter) {
+			noGlob = false
+			break
+		}
+	}
+
+	switch {
+	case noGlob:
+		// return non-globbing filter if not needed.
+		return compileFilterNoGlob(filters), nil
+	case len(filters) == 1:
+		return glob.Compile(filters[0])
+	default:
+		return glob.Compile("{" + strings.Join(filters, ",") + "}")
+	}
+}
+
+// hasMeta reports whether path contains any magic glob characters.
+func hasMeta(s string) bool {
+	return strings.ContainsAny(s, "*?[")
+}
+
+type filter struct {
+	m map[string]struct{}
+}
+
+func (f *filter) Match(s string) bool {
+	_, ok := f.m[s]
+	return ok
+}
+
+type filtersingle struct {
+	s string
+}
+
+func (f *filtersingle) Match(s string) bool {
+	return f.s == s
+}
+
+func compileFilterNoGlob(filters []string) Filter {
+	if len(filters) == 1 {
+		return &filtersingle{s: filters[0]}
+	}
+	out := filter{m: make(map[string]struct{})}
+	for _, filter := range filters {
+		out.m[filter] = struct{}{}
+	}
+	return &out
+}
+
+type IncludeExcludeFilter struct {
+	include        Filter
+	exclude        Filter
+	includeDefault bool
+	excludeDefault bool
+}
+
+func NewIncludeExcludeFilter(
+	include []string,
+	exclude []string,
+) (Filter, error) {
+	return NewIncludeExcludeFilterDefaults(include, exclude, true, false)
+}
+
+func NewIncludeExcludeFilterDefaults(
+	include []string,
+	exclude []string,
+	includeDefault bool,
+	excludeDefault bool,
+) (Filter, error) {
+	in, err := Compile(include)
+	if err != nil {
+		return nil, err
+	}
+
+	ex, err := Compile(exclude)
+	if err != nil {
+		return nil, err
+	}
+
+	return &IncludeExcludeFilter{in, ex, includeDefault, excludeDefault}, nil
+}
+
+func (f *IncludeExcludeFilter) Match(s string) bool {
+	if f.include != nil {
+		if !f.include.Match(s) {
+			return false
+		}
+	} else if !f.includeDefault {
+		return false
+	}
+
+	if f.exclude != nil {
+		if f.exclude.Match(s) {
+			return false
+		}
+	} else if f.excludeDefault {
+		return false
+	}
+
+	return true
+}
diff --git a/cli/internal/util/filter/filter_test.go b/cli/internal/util/filter/filter_test.go
new file mode 100644
index 0000000..727a4b6
--- /dev/null
+++ b/cli/internal/util/filter/filter_test.go
@@ -0,0 +1,116 @@
+// Copyright (c) 2015-2020 InfluxData Inc. MIT License (MIT)
+// https://github.com/influxdata/telegraf
+package filter
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCompile(t *testing.T) {
+	f, err := Compile([]string{})
+	assert.NoError(t, err)
+	assert.Nil(t, f)
+
+	f, err = Compile([]string{"cpu"})
+	assert.NoError(t, err)
+	assert.True(t, f.Match("cpu"))
+	assert.False(t, f.Match("cpu0"))
+	assert.False(t, f.Match("mem"))
+
+	f, err = Compile([]string{"cpu*"})
+	assert.NoError(t, err)
+	assert.True(t, f.Match("cpu"))
+	assert.True(t, f.Match("cpu0"))
+	assert.False(t, f.Match("mem"))
+
+	f, err = Compile([]string{"cpu", "mem"})
+	assert.NoError(t, err)
+	assert.True(t, f.Match("cpu"))
+	assert.False(t, f.Match("cpu0"))
+	assert.True(t, f.Match("mem"))
+
+	f, err = Compile([]string{"cpu", "mem", "net*"})
+	assert.NoError(t, err)
+	assert.True(t, f.Match("cpu"))
+	assert.False(t, f.Match("cpu0"))
+	assert.True(t, f.Match("mem"))
+	assert.True(t, f.Match("network"))
+}
+
+func TestIncludeExclude(t *testing.T) {
+	tags := []string{}
+	labels := []string{"best", "com_influxdata", "timeseries", "com_influxdata_telegraf", "ever"}
+
+	filter, err := NewIncludeExcludeFilter([]string{}, []string{"com_influx*"})
+	if err != nil {
+		t.Fatalf("Failed to create include/exclude filter - %v", err)
+	}
+
+	for i := range labels {
+		if filter.Match(labels[i]) {
+			tags = append(tags, labels[i])
+		}
+	}
+
+	assert.Equal(t, []string{"best", "timeseries", "ever"}, tags)
+}
+
+var benchbool bool
+
+func BenchmarkFilterSingleNoGlobFalse(b *testing.B) {
+	f, _ := Compile([]string{"cpu"})
+	var tmp bool
+	for n := 0; n < b.N; n++ {
+		tmp = f.Match("network")
+	}
+	benchbool = tmp
+}
+
+func BenchmarkFilterSingleNoGlobTrue(b *testing.B) {
+	f, _ := Compile([]string{"cpu"})
+	var tmp bool
+	for n := 0; n < b.N; n++ {
+		tmp = f.Match("cpu")
+	}
+	benchbool = tmp
+}
+
+func BenchmarkFilter(b *testing.B) {
+	f, _ := Compile([]string{"cpu", "mem", "net*"})
+	var tmp bool
+	for n := 0; n < b.N; n++ {
+		tmp = f.Match("network")
+	}
+	benchbool = tmp
+}
+
+func BenchmarkFilterNoGlob(b *testing.B) {
+	f, _ := Compile([]string{"cpu", "mem", "net"})
+	var tmp bool
+	for n := 0; n < b.N; n++ {
+		tmp = f.Match("net")
+	}
+	benchbool = tmp
+}
+
+func BenchmarkFilter2(b *testing.B) {
+	f, _ := Compile([]string{"aa", "bb", "c", "ad", "ar", "at", "aq",
+		"aw", "az", "axxx", "ab", "cpu", "mem", "net*"})
+	var tmp bool
+	for n := 0; n < b.N; n++ {
+		tmp = f.Match("network")
+	}
+	benchbool = tmp
+}
+
+func BenchmarkFilter2NoGlob(b *testing.B) {
+	f, _ := Compile([]string{"aa", "bb", "c", "ad", "ar", "at", "aq",
+		"aw", "az", "axxx", "ab", "cpu", "mem", "net"})
+	var tmp bool
+	for n := 0; n < b.N; n++ {
+		tmp = f.Match("net")
+	}
+	benchbool = tmp
+}