update to github.com/sirupsen/logrus v1.0.0

Signed-off-by: Andrew Pennebaker <apennebaker@datapipe.com>

vendor/github.com/sirupsen/logrus/json_formatter.go

@@ -0,0 +1,74 @@
+package logrus
+
+import (
+	"encoding/json"
+	"fmt"
+)
+
+type fieldKey string
+type FieldMap map[fieldKey]string
+
+const (
+	FieldKeyMsg   = "msg"
+	FieldKeyLevel = "level"
+	FieldKeyTime  = "time"
+)
+
+func (f FieldMap) resolve(key fieldKey) string {
+	if k, ok := f[key]; ok {
+		return k
+	}
+
+	return string(key)
+}
+
+type JSONFormatter struct {
+	// TimestampFormat sets the format used for marshaling timestamps.
+	TimestampFormat string
+
+	// DisableTimestamp allows disabling automatic timestamps in output
+	DisableTimestamp bool
+
+	// FieldMap allows users to customize the names of keys for various fields.
+	// As an example:
+	// formatter := &JSONFormatter{
+	//   	FieldMap: FieldMap{
+	// 		 FieldKeyTime: "@timestamp",
+	// 		 FieldKeyLevel: "@level",
+	// 		 FieldKeyMsg: "@message",
+	//    },
+	// }
+	FieldMap FieldMap
+}
+
+func (f *JSONFormatter) Format(entry *Entry) ([]byte, error) {
+	data := make(Fields, len(entry.Data)+3)
+	for k, v := range entry.Data {
+		switch v := v.(type) {
+		case error:
+			// Otherwise errors are ignored by `encoding/json`
+			// https://github.com/sirupsen/logrus/issues/137
+			data[k] = v.Error()
+		default:
+			data[k] = v
+		}
+	}
+	prefixFieldClashes(data)
+
+	timestampFormat := f.TimestampFormat
+	if timestampFormat == "" {
+		timestampFormat = DefaultTimestampFormat
+	}
+
+	if !f.DisableTimestamp {
+		data[f.FieldMap.resolve(FieldKeyTime)] = entry.Time.Format(timestampFormat)
+	}
+	data[f.FieldMap.resolve(FieldKeyMsg)] = entry.Message
+	data[f.FieldMap.resolve(FieldKeyLevel)] = entry.Level.String()
+
+	serialized, err := json.Marshal(data)
+	if err != nil {
+		return nil, fmt.Errorf("Failed to marshal fields to JSON, %v", err)
+	}
+	return append(serialized, '\n'), nil
+}