promtail

README

promtail golang client

The purpose of this small library is creating a tool for upload logs to grafana loki. The logs looks pretty amazing and awesome, we can have static labels or dynamic labels for filtering while we're debugging.

promtail client for golang services

// create a promtail client
promtail, pErr := client.NewSimpleClient(host, username, password,
    client.WithStaticLabels(map[string]interface{}{
        "app": "awesome-service",
    }),
    client.WithStreamConverter(promtail.NewRawStreamConv(labels, "=")),
)
if pErr != nil {
    panic(pErr)
}

// now can be used as a Writer for any logger

// setup any logger and use as the output, can be combined with many outputs using io.MultiWriter
output := zerolog.ConsoleWriter{Out: promtail}
output.FormatMessage = func(i interface{}) string {
    _, ok := i.(string)
    if ok {
        return fmt.Sprintf("%-50s", i)
    } else {
        return ""
    }
}
output.FormatLevel = func(i interface{}) string {
    _, ok := i.(string)
    if ok {
        return fmt.Sprintf("level=%-7s", i)
    } else {
        return "level=info"
    }
}
log.Logger = log.Output(output)

log.Info().
    Str("my_label", "some_value").
    Msg("the message")

Documentation

Index

• type Entry
• type HttpClient
• type LabelSet
• type PushRequest
• type Stream
• type StreamConverter
  • func NewRawStreamConv(labels, sep string) StreamConverter

Types

type Entry

type Entry []interface{}

type HttpClient

type HttpClient interface {
	Push(ctx context.Context, request PushRequest) error
}

type LabelSet

type LabelSet map[string]interface{}

LabelSet is a key/value pair mapping of labels

type PushRequest

type PushRequest struct {
	Streams []*Stream `json:"streams"`
}

PushRequest models a log stream push

type Stream

type Stream struct {
	Labels  LabelSet `json:"stream"`
	Entries []Entry  `json:"values"`
}

Stream represents a log stream. It includes a set of log entries and their labels.

type StreamConverter

type StreamConverter interface {
	ConvertEntry([]byte) (Entry, error)
	ExtractLabels([]byte) (LabelSet, error)
}

func NewRawStreamConv

func NewRawStreamConv(labels, sep string) StreamConverter