provide default config for logging (#183)

* provide default config for logging

* swap the json/yaml parsers for viper

Author: rybit

nconf/args.go

@@ -18,30 +18,24 @@ type RootArgs struct {
 	ConfigFile string
 }
 
-func (args *RootArgs) Setup(config interface{}, serviceName, version string) (logrus.FieldLogger, error) {
-	// first load the logger and BugSnag config
-	rootConfig := &struct {
-		Log         *LoggingConfig
-		BugSnag     *BugSnagConfig
-		Metrics     metriks.Config
-		Tracing     tracing.Config
-		FeatureFlag featureflag.Config
-	}{}
+type RootConfig struct {
+	Log         LoggingConfig
+	BugSnag     BugSnagConfig      `mapstructure:",squash"`
+	Metrics     metriks.Config     `mapstructure:",squash"`
+	Tracing     tracing.Config     `mapstructure:",squash"`
+	FeatureFlag featureflag.Config `mapstructure:",squash"`
+}
 
-	loader := func(cfg interface{}) error {
-		return LoadFromEnv(args.Prefix, args.ConfigFile, cfg)
-	}
-	if !strings.HasSuffix(args.ConfigFile, ".env") {
-		loader = func(cfg interface{}) error {
-			return LoadFromFile(args.ConfigFile, cfg)
-		}
+func (args *RootArgs) Setup(config interface{}, serviceName, version string) (logrus.FieldLogger, error) {
+	rootConfig := RootConfig{
+		Log: DefaultLoggingConfig,
 	}
 
-	if err := loader(rootConfig); err != nil {
-		return nil, errors.Wrap(err, "Failed to load the logging configuration")
+	if err := args.load(&rootConfig); err != nil {
+		return nil, errors.Wrap(err, "Failed to load the root configuration")
 	}
 
-	log, err := ConfigureLogging(rootConfig.Log)
+	log, err := ConfigureLogging(&rootConfig.Log)
 	if err != nil {
 		return nil, errors.Wrap(err, "Failed to create the logger")
 	}
@@ -50,7 +44,7 @@ func (args *RootArgs) Setup(config interface{}, serviceName, version string) (lo
 	}
 	log = log.WithField("version", version)
 
-	if err := SetupBugSnag(rootConfig.BugSnag, version); err != nil {
+	if err := SetupBugSnag(&rootConfig.BugSnag, version); err != nil {
 		return nil, errors.Wrap(err, "Failed to configure bugsnag")
 	}
 
@@ -71,14 +65,26 @@ func (args *RootArgs) Setup(config interface{}, serviceName, version string) (lo
 
 	if config != nil {
 		// second load the config for this project
-		if err := loader(config); err != nil {
+		if err := args.load(config); err != nil {
 			return log, errors.Wrap(err, "Failed to load the config object")
 		}
 		log.Debug("Loaded configuration")
 	}
 	return log, nil
 }
 
+func (args *RootArgs) load(cfg interface{}) error {
+	loader := func(cfg interface{}) error {
+		return LoadFromEnv(args.Prefix, args.ConfigFile, cfg)
+	}
+	if !strings.HasSuffix(args.ConfigFile, ".env") {
+		loader = func(cfg interface{}) error {
+			return LoadFromFile(args.ConfigFile, cfg)
+		}
+	}
+	return loader(cfg)
+}
+
 func (args *RootArgs) MustSetup(config interface{}, serviceName, version string) logrus.FieldLogger {
 	logger, err := args.Setup(config, serviceName, version)
 	if err != nil {

nconf/args_test.go

@@ -2,6 +2,7 @@ package nconf
 
 import (
 	"io/ioutil"
+	"os"
 	"testing"
 
 	"github.com/spf13/cobra"
@@ -67,3 +68,45 @@ func TestArgsAddToCmd(t *testing.T) {
 	require.NoError(t, cmd.Execute())
 	assert.Equal(t, 1, called)
 }
+
+func TestArgsLoadFromYAML(t *testing.T) {
+	f, err := ioutil.TempFile("", "test-config-*.yaml")
+	require.NoError(t, err)
+	defer os.Remove(f.Name())
+
+	args := RootArgs{
+		ConfigFile: f.Name(),
+	}
+
+	t.Run("empty-file", func(t *testing.T) {
+		cfg := RootConfig{
+			Log: DefaultLoggingConfig,
+		}
+		require.NoError(t, args.load(&cfg))
+
+		assert.True(t, cfg.Log.QuoteEmptyFields)
+		assert.Equal(t, DefaultLoggingConfig, cfg.Log)
+		assert.Empty(t, cfg.BugSnag.APIKey)
+	})
+
+	_, err = f.WriteString(`
+log:
+  level: debug
+  fields:
+    string: value
+    int: 4
+`)
+	require.NoError(t, err)
+
+	t.Run("set log field", func(t *testing.T) {
+		cfg := RootConfig{Log: DefaultLoggingConfig}
+		require.NoError(t, args.load(&cfg))
+
+		// retains original value
+		assert.True(t, cfg.Log.QuoteEmptyFields)
+		assert.Equal(t, "debug", cfg.Log.Level)
+		require.Len(t, cfg.Log.Fields, 2)
+		assert.Equal(t, "value", cfg.Log.Fields["string"])
+		assert.Equal(t, 4, cfg.Log.Fields["int"])
+	})
+}

nconf/configuration.go

@@ -1,13 +1,14 @@
 package nconf
 
 import (
+	"encoding/json"
+	"io/ioutil"
 	"os"
 	"strings"
 
 	"github.com/joho/godotenv"
 	"github.com/kelseyhightower/envconfig"
-	"github.com/pkg/errors"
-	"github.com/spf13/viper"
+	"gopkg.in/yaml.v3"
 )
 
 // LoadFromFile will load the configuration from the specified file based on the file type
@@ -17,24 +18,21 @@ func LoadFromFile(configFile string, input interface{}) error {
 		return nil
 	}
 
+	// read in all the bytes
+	data, err := ioutil.ReadFile(configFile)
+	if err != nil {
+		return err
+	}
+
 	switch {
 	case strings.HasSuffix(configFile, ".json"):
-		viper.SetConfigType("json")
+		err = json.Unmarshal(data, input)
 	case strings.HasSuffix(configFile, ".yaml"):
 		fallthrough
 	case strings.HasSuffix(configFile, ".yml"):
-		viper.SetConfigType("yaml")
+		err = yaml.Unmarshal(data, input)
 	}
-	viper.SetConfigFile(configFile)
-
-	if err := viper.ReadInConfig(); err != nil && !os.IsNotExist(err) {
-		_, ok := err.(viper.ConfigFileNotFoundError)
-		if !ok {
-			return errors.Wrap(err, "reading configuration from files")
-		}
-	}
-
-	return viper.Unmarshal(input)
+	return err
 }
 
 func LoadFromEnv(prefix, filename string, face interface{}) error {

nconf/configuration_test.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
+	"gopkg.in/yaml.v3"
 )
 
 type testConfig struct {
@@ -96,7 +97,7 @@ func TestFileLoadJSON(t *testing.T) {
 
 func TestFileLoadYAML(t *testing.T) {
 	expected := exampleConfig()
-	bytes, err := json.Marshal(&expected)
+	bytes, err := yaml.Marshal(&expected)
 	require.NoError(t, err)
 	filename := writeTestFile(t, "yaml", bytes)
 	defer os.Remove(filename)

nconf/logging.go

@@ -17,9 +17,19 @@ type LoggingConfig struct {
 	UseNewLogger     bool                   `mapstructure:"use_new_logger",split_words:"true"`
 }
 
+var DefaultLoggingConfig = LoggingConfig{
+	Level:            "info",
+	QuoteEmptyFields: true,
+	Fields:           make(map[string]interface{}),
+}
+
 func ConfigureLogging(config *LoggingConfig) (*logrus.Entry, error) {
 	logger := logrus.New()
 
+	if config == nil {
+		config = &DefaultLoggingConfig
+	}
+
 	tsFormat := time.RFC3339Nano
 	if config.TSFormat != "" {
 		tsFormat = config.TSFormat