[jaeger-v2] Add Validation And Comments to Badger Storage Config

plugin/storage/badger/options.go

@@ -9,6 +9,7 @@ import (
 	"path/filepath"
 	"time"
 
+	"github.com/asaskevich/govalidator"
 	"github.com/spf13/viper"
 	"go.uber.org/zap"
 )
@@ -19,18 +20,33 @@ type Options struct {
 	// This storage plugin does not support additional namespaces
 }
 
-// NamespaceConfig is badger's internal configuration data
+// NamespaceConfig is badger's internal configuration data.
 type NamespaceConfig struct {
-	namespace      string
-	SpanStoreTTL   time.Duration `mapstructure:"span_store_ttl"`
-	ValueDirectory string        `mapstructure:"directory_value"`
-	KeyDirectory   string        `mapstructure:"directory_key"`
-	// Setting this to true will ignore ValueDirectory and KeyDirectory
-	Ephemeral             bool          `mapstructure:"ephemeral"`
-	SyncWrites            bool          `mapstructure:"consistency"`
-	MaintenanceInterval   time.Duration `mapstructure:"maintenance_interval"`
+	namespace string
+	// SpanStoreTTL holds the amount of time that the span store data is stored.
+	// Once this duration has passed for a given key, it will no longer be accessible.
+	SpanStoreTTL time.Duration `mapstructure:"span_store_ttl"`
+	// KeyDirectory is the directory in which the keys are stored. Ephemeral must be
+	// set to false for this configuration to take effect.
+	KeyDirectory string `mapstructure:"directory_key"`
+	// ValueDirectory is the directory in which the values should be stored. Ephemeral must be
+	// set to false for this configuration to take effect.
+	ValueDirectory string `mapstructure:"directory_value"`
+	// Ephemeral, if set to true, will store data in a temporary file system.
+	// If set to true, KeyDirectory and ValueDirectory are ignored.
+	Ephemeral bool `mapstructure:"ephemeral"`
+	// SyncWrites, if set to true, will immediately sync all writes to disk. Note that
+	// setting this field to true will affect write performance.
+	SyncWrites bool `mapstructure:"consistency"`
+	// MaintenanceInterval is the regular interval after which a maintenance job is
+	// run on the values in the store.
+	MaintenanceInterval time.Duration `mapstructure:"maintenance_interval"`
+	// MetricsUpdateInterval is the regular interval after which metrics are collected
+	// by Jaeger.
 	MetricsUpdateInterval time.Duration `mapstructure:"metrics_update_interval"`
-	ReadOnly              bool          `mapstructure:"read_only"`
+	// ReadOnly opens the data store in read-only mode. Multiple instances can open the same
+	// store in read-only mode. Values still in the write-ahead-log must be replayed before opening.
+	ReadOnly bool `mapstructure:"read_only"`
 }
 
 const (
@@ -152,3 +168,8 @@ func initFromViper(cfg *NamespaceConfig, v *viper.Viper, _ *zap.Logger) {
 func (opt *Options) GetPrimary() NamespaceConfig {
 	return opt.Primary
 }
+
+func (c *NamespaceConfig) Validate() error {
+	_, err := govalidator.ValidateStruct(c)
+	return err
+}

plugin/storage/badger/options_test.go

@@ -8,6 +8,7 @@ import (
 	"time"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"go.uber.org/zap"
 
 	"github.com/jaegertracing/jaeger/pkg/config"
@@ -53,3 +54,35 @@ func TestReadOnlyOptions(t *testing.T) {
 	opts.InitFromViper(v, zap.NewNop())
 	assert.True(t, opts.GetPrimary().ReadOnly)
 }
+
+func TestValidate_DoesNotReturnErrorWhenValid(t *testing.T) {
+	tests := []struct {
+		name   string
+		config *NamespaceConfig
+	}{
+		{
+			name:   "non-required fields not set",
+			config: &NamespaceConfig{},
+		},
+		{
+			name: "all fields are set",
+			config: &NamespaceConfig{
+				SpanStoreTTL:          time.Second,
+				KeyDirectory:          "some-key-directory",
+				ValueDirectory:        "some-value-directory",
+				Ephemeral:             false,
+				SyncWrites:            false,
+				MaintenanceInterval:   time.Second,
+				MetricsUpdateInterval: time.Second,
+				ReadOnly:              false,
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			err := test.config.Validate()
+			require.NoError(t, err)
+		})
+	}
+}