support for .yaml.local in go bouncer

config.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"fmt"
+	"io"
 	"os"
 	"time"
 
@@ -42,20 +43,29 @@ type bouncerConfig struct {
 	PrometheusConfig           PrometheusConfig `yaml:"prometheus"`
 }
 
-func NewConfig(configPath string) (*bouncerConfig, error) {
+// mergedConfig() returns the byte content of the patched configuration file (with .yaml.local).
+func mergedConfig(configPath string) ([]byte, error) {
+	patcher := yamlpatch.NewPatcher(configPath, ".local")
+	data, err := patcher.MergedPatchContent()
+	if err != nil {
+		return nil, err
+	}
+	return data, nil
+}
+
+func newConfig(reader io.Reader) (*bouncerConfig, error) {
 	var LogOutput *lumberjack.Logger //io.Writer
 
 	config := &bouncerConfig{}
 
-	patcher := yamlpatch.NewPatcher(configPath, ".local")
-	fcontent, err := patcher.MergedPatchContent()
+	fcontent, err := io.ReadAll(reader)
 	if err != nil {
 		return &bouncerConfig{}, err
 	}
 
 	err = yaml.Unmarshal(fcontent, &config)
 	if err != nil {
-		return &bouncerConfig{}, fmt.Errorf("failed to unmarshal %s : %v", configPath, err)
+		return &bouncerConfig{}, fmt.Errorf("failed to unmarshal: %w", err)
 	}
 
 	if config.BinPath == "" {

custom_test.go

@@ -2,7 +2,6 @@ package main
 
 import (
 	"fmt"
-	"io/ioutil"
 	"os"
 	"reflect"
 	"strings"
@@ -33,7 +32,7 @@ type parsedLine struct {
 }
 
 func parseFile(path string) []parsedLine {
-	dat, err := ioutil.ReadFile(binaryOutputFile)
+	dat, err := os.ReadFile(binaryOutputFile)
 	parsedLines := make([]parsedLine, 0)
 	if err != nil {
 		panic(err)

go.sum

@@ -180,7 +180,6 @@ github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA
 github.com/census-instrumentation/opencensus-proto v0.3.0/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/certifi/gocertifi v0.0.0-20191021191039-0944d244cd40/go.mod h1:sGbDF6GwGcLpkNXPUTkMRoywsNa/ol15pxFe6ERfguA=
 github.com/certifi/gocertifi v0.0.0-20200922220541-2c3bb06c6054/go.mod h1:sGbDF6GwGcLpkNXPUTkMRoywsNa/ol15pxFe6ERfguA=
-github.com/cespare/xxhash v1.1.0 h1:a6HrQnmkObjyL+Gs60czilIUGqrzKutQD6XZog3p+ko=
 github.com/cespare/xxhash v1.1.0/go.mod h1:XrSqR1VqqWfGrhpAt58auRo0WTKS1nRRg3ghfAqPWnc=
 github.com/cespare/xxhash/v2 v2.1.1/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/cespare/xxhash/v2 v2.1.2 h1:YRXhKfTDauu4ajMg1TPgFO5jnlC2HCbmLXMcTG5cbYE=

main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"context"
 	"flag"
 	"fmt"
@@ -87,7 +88,12 @@ func main() {
 		},
 	})
 
-	config, err := NewConfig(*configPath)
+	configBytes, err := mergedConfig(*configPath)
+	if err != nil {
+		log.Fatalf("unable to read config file: %s", err)
+	}
+
+	config, err := newConfig(bytes.NewReader(configBytes))
 	if err != nil {
 		log.Fatalf("unable to load configuration: %s", err)
 	}