slog: Slack handler
January 25, 2026 ยท View on GitHub
A Slack Handler for slog Go library.
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Simple to use, built on open standards, and designed for full cost control
See also:
- slog-multi:
slog.Handlerchaining, fanout, routing, failover, load balancing... - slog-formatter:
slogattribute formatting - slog-sampling:
slogsampling policy - slog-mock:
slog.Handlerfor test purposes
HTTP middlewares:
- slog-gin: Gin middleware for
sloglogger - slog-echo: Echo middleware for
sloglogger - slog-fiber: Fiber middleware for
sloglogger - slog-chi: Chi middleware for
sloglogger - slog-http:
net/httpmiddleware forsloglogger
Loggers:
- slog-zap: A
sloghandler forZap - slog-zerolog: A
sloghandler forZerolog - slog-logrus: A
sloghandler forLogrus
Log sinks:
- slog-datadog: A
sloghandler forDatadog - slog-betterstack: A
sloghandler forBetterstack - slog-rollbar: A
sloghandler forRollbar - slog-loki: A
sloghandler forLoki - slog-sentry: A
sloghandler forSentry - slog-syslog: A
sloghandler forSyslog - slog-logstash: A
sloghandler forLogstash - slog-fluentd: A
sloghandler forFluentd - slog-graylog: A
sloghandler forGraylog - slog-quickwit: A
sloghandler forQuickwit - slog-slack: A
sloghandler forSlack - slog-telegram: A
sloghandler forTelegram - slog-mattermost: A
sloghandler forMattermost - slog-microsoft-teams: A
sloghandler forMicrosoft Teams - slog-webhook: A
sloghandler forWebhook - slog-kafka: A
sloghandler forKafka - slog-nats: A
sloghandler forNATS - slog-parquet: A
sloghandler forParquet+Object Storage - slog-channel: A
sloghandler for Go channels
๐ Install
go get github.com/samber/slog-slack/v2
Compatibility: go >= 1.21
No breaking changes will be made to exported APIs before v3.0.0.
๐ก Usage
GoDoc: https://pkg.go.dev/github.com/samber/slog-slack/v2
Handler options
type Option struct {
// log level (default: debug)
Level slog.Leveler
// slack webhook url
WebhookURL string
// slack bot token
BotToken string
// slack channel (default: webhook channel)
Channel string
// bot username (default: webhook username)
Username string
// bot emoji (default: webhook emoji)
IconEmoji string
// bot emoji (default: webhook emoji)
IconURL string
// Not implemented yet, but we would like your feedback here: #7
// ThreadTimestamp string
// API request timeout (default: 10s)
Timeout time.Duration
// optional: customize Slack message builder
Converter Converter
// optional: see slog.HandlerOptions
AddSource bool
ReplaceAttr func(groups []string, a slog.Attr) slog.Attr
}
Attributes will be injected in message attachments.
Other global parameters:
slogslack.SourceKey = "source"
slogslack.ColorMapping = map[slog.Level]string{...}

Example
Using webhook
Generate a webhook here.
import (
slogslack "github.com/samber/slog-slack/v2"
"log/slog"
)
func main() {
webhook := "https://hooks.slack.com/services/xxx/yyy/zzz"
channel := "alerts"
logger := slog.New(slogslack.Option{Level: slog.LevelError, WebhookURL: webhook, Channel: channel}.NewSlackHandler())
logger = logger.
With("environment", "dev").
With("release", "v1.0.0")
// log error
logger.
With("category", "sql").
With("query.statement", "SELECT COUNT(*) FROM users;").
With("query.duration", 1*time.Second).
With("error", fmt.Errorf("could not count users")).
Error("caramba!")
// log user signup
logger.
With(
slog.Group("user",
slog.String("id", "user-123"),
slog.Time("created_at", time.Now()),
),
).
Info("user registration")
// push record to a thread
logger.ErrorContext(
slogslack.WithThreadTimestamp(context.Background(), "1714929099.4238"),
"An error",
)
}
Using bot token
Use Bot token.
import (
slogslack "github.com/samber/slog-slack/v2"
"log/slog"
)
func main() {
token := "xoxb-"
channel := "alerts"
logger := slog.New(slogslack.Option{Level: slog.LevelError, BotToken: token, Channel: channel}.NewSlackHandler())
logger = logger.
With("environment", "dev").
With("release", "v1.0.0")
}
๐ค Contributing
- Ping me on twitter @samuelberthe (DMs, mentions, whatever :))
- Fork the project
- Fix open issues or request new features
Don't hesitate ;)
# Install some dev dependencies
make tools
# Run tests
make test
# or
make watch-test
๐ค Contributors
๐ซ Show your support
Give a โญ๏ธ if this project helped you!
๐ License
Copyright ยฉ 2023 Samuel Berthe.
This project is MIT licensed.