Add regexp sync type (#142)

* Add new sync.Regexp type

* Driveby: fix missing and incorrect docs

Author: peterklijn

README.md

@@ -45,7 +45,9 @@ The fields have to be one of the types that the sync package supports in order t
 - sync.Bool, allows for concurrent bool manipulation
 - sync.Secret, allows for concurrent secret manipulation. Secrets can only be strings
 - sync.TimeDuration, allows for concurrent time.duration manipulation.
+- sync.Regexp, allows for concurrent *regexp.Regexp manipulation.
 - sync.StringMap, allows for concurrent map[string]string manipulation.
+- sync.StringSlice, allows for concurrent []string manipulation.
 
 For sensitive configuration (passwords, tokens, etc.) that shouldn't be printed in log, you can use the `Secret` flavor of `sync` types. If one of these is selected, then at harvester log instead of the real value the text `***` will be displayed.
 

sync/sync.go

@@ -5,6 +5,7 @@ import (
 	"bytes"
 	"encoding/json"
 	"fmt"
+	"regexp"
 	"strconv"
 	"strings"
 	"sync"
@@ -38,7 +39,7 @@ func (b *Bool) MarshalJSON() ([]byte, error) {
 	return json.Marshal(b.value)
 }
 
-// MarshalJSON returns the JSON encoding of the value.
+// UnmarshalJSON returns the JSON encoding of the value.
 func (b *Bool) UnmarshalJSON(d []byte) error {
 	b.rw.RLock()
 	defer b.rw.RUnlock()
@@ -92,7 +93,7 @@ func (i *Int64) MarshalJSON() ([]byte, error) {
 	return json.Marshal(i.value)
 }
 
-// MarshalJSON returns the JSON encoding of the value.
+// UnmarshalJSON returns the JSON encoding of the value.
 func (i *Int64) UnmarshalJSON(d []byte) error {
 	i.rw.RLock()
 	defer i.rw.RUnlock()
@@ -143,7 +144,7 @@ func (f *Float64) MarshalJSON() ([]byte, error) {
 	return json.Marshal(f.value)
 }
 
-// MarshalJSON returns the JSON encoding of the value.
+// UnmarshalJSON returns the JSON encoding of the value.
 func (f *Float64) UnmarshalJSON(d []byte) error {
 	f.rw.RLock()
 	defer f.rw.RUnlock()
@@ -194,7 +195,7 @@ func (s *String) MarshalJSON() ([]byte, error) {
 	return json.Marshal(s.value)
 }
 
-// MarshalJSON returns the JSON encoding of the value.
+// UnmarshalJSON returns the JSON encoding of the value.
 func (s *String) UnmarshalJSON(d []byte) error {
 	s.rw.RLock()
 	defer s.rw.RUnlock()
@@ -241,7 +242,7 @@ func (s *TimeDuration) MarshalJSON() ([]byte, error) {
 	return json.Marshal(s.value)
 }
 
-// MarshalJSON returns the JSON encoding of the value.
+// UnmarshalJSON returns the JSON encoding of the value.
 func (s *TimeDuration) UnmarshalJSON(d []byte) error {
 	s.rw.RLock()
 	defer s.rw.RUnlock()
@@ -290,7 +291,7 @@ func (s *Secret) MarshalJSON() (out []byte, err error) {
 	return json.Marshal(s.String())
 }
 
-// MarshalJSON returns the JSON encoding of the value.
+// UnmarshalJSON returns the JSON encoding of the value.
 func (s *Secret) UnmarshalJSON(d []byte) error {
 	s.rw.RLock()
 	defer s.rw.RUnlock()
@@ -308,6 +309,67 @@ func (s *Secret) SetString(val string) error {
 	return nil
 }
 
+type Regexp struct {
+	rw    sync.RWMutex
+	value *regexp.Regexp
+}
+
+// Get returns the internal value.
+func (r *Regexp) Get() *regexp.Regexp {
+	r.rw.RLock()
+	defer r.rw.RUnlock()
+	return r.value
+}
+
+// Set a value.
+func (r *Regexp) Set(value *regexp.Regexp) {
+	r.rw.Lock()
+	defer r.rw.Unlock()
+	r.value = value
+}
+
+// MarshalJSON returns the JSON encoding of the value.
+func (r *Regexp) MarshalJSON() ([]byte, error) {
+	r.rw.RLock()
+	defer r.rw.RUnlock()
+	return json.Marshal(r.value.String())
+}
+
+// UnmarshalJSON returns the JSON encoding of the value.
+func (r *Regexp) UnmarshalJSON(d []byte) error {
+	var str string
+	err := json.Unmarshal(d, &str)
+	if err != nil {
+		fmt.Println("json unmarshal")
+		return err
+	}
+	regex, err := regexp.Compile(str)
+	if err != nil {
+		fmt.Println("regex compile")
+		return err
+	}
+	r.Set(regex)
+	return nil
+}
+
+// String returns a string representation of the value.
+func (r *Regexp) String() string {
+	r.rw.RLock()
+	defer r.rw.RUnlock()
+	return r.value.String()
+}
+
+//
+// SetString parses and sets a value from string type.
+func (r *Regexp) SetString(val string) error {
+	compiled, err := regexp.Compile(val)
+	if err != nil {
+		return err
+	}
+	r.Set(compiled)
+	return nil
+}
+
 // StringMap is a map[string]string type with concurrent access support.
 type StringMap struct {
 	rw    sync.RWMutex

sync/sync_test.go

@@ -2,6 +2,7 @@ package sync
 
 import (
 	"fmt"
+	"regexp"
 	"testing"
 	"time"
 
@@ -207,6 +208,65 @@ func TestTimeDuration_UnmarshalJSON(t *testing.T) {
 	assert.Equal(t, time.Duration(1), b.Get())
 }
 
+func TestRegexp(t *testing.T) {
+	regex := regexp.MustCompile(".*")
+
+	var r Regexp
+	ch := make(chan struct{})
+	go func() {
+		r.Set(regex)
+		ch <- struct{}{}
+	}()
+	<-ch
+	assert.Equal(t, regex, r.Get())
+	assert.Equal(t, regex.String(), r.String())
+
+	d, err := r.MarshalJSON()
+	assert.NoError(t, err)
+	assert.Equal(t, `".*"`, string(d))
+}
+
+func TestRegexp_UnmarshalJSON(t *testing.T) {
+	var r Regexp
+	err := r.UnmarshalJSON([]byte(`invalid json`))
+	assert.Error(t, err)
+	assert.Nil(t, r.Get())
+
+	// Invalid regex:
+	err = r.UnmarshalJSON([]byte(`"[a-z]++"`))
+	assert.Error(t, err)
+	assert.Nil(t, r.Get())
+
+	err = r.UnmarshalJSON([]byte(`"[a-z0-7]+"`))
+	assert.NoError(t, err)
+	assert.Equal(t, regexp.MustCompile("[a-z0-7]+"), r.Get())
+}
+
+func TestRegexp_SetString(t *testing.T) {
+	tests := []struct {
+		name        string
+		input       string
+		result      *regexp.Regexp
+		throwsError bool
+	}{
+		{"empty", "", regexp.MustCompile(""), false},
+		{"simple regex", ".*", regexp.MustCompile(".*"), false},
+		{"invalid regex", "[0-9]++", nil, true},
+	}
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			sr := Regexp{}
+
+			err := sr.SetString(test.input)
+			if test.throwsError {
+				assert.Error(t, err)
+			}
+
+			assert.Equal(t, test.result, sr.Get())
+		})
+	}
+}
+
 func TestStringMap(t *testing.T) {
 	var sm StringMap
 	ch := make(chan struct{})