xmidt-org/themis

package xhealth

import (
    "context"

    health "github.com/InVisionApp/go-health"
    "github.com/go-kit/kit/log"
    "github.com/go-kit/kit/log/level"
    "github.com/xmidt-org/themis/xlog"
)

// Options holds the available configuration options for the health infrastructure
type Options struct {
    // DisableLogging controls whether the created health service logs anything.  The default is false,
    // meaning logging is enabled.
    DisableLogging bool

    // Custom is an optional map passed to NewHandler that is included in all responses to health checks
    Custom map[string]interface{}
}

// New constructs an IHealth instance for the given environment.  If either the DisableLogging option field
// is set or the given logger is nil, logging will be disabled on the returned health object.  The listener
// is optional.
func New(o Options, logger log.Logger, listener health.IStatusListener) (health.IHealth, error) {
    h := health.New()
    if o.DisableLogging || logger == nil {
        h.DisableLogging()
    } else {
        h.Logger = NewHealthLoggerAdapter(logger)
    }

    h.StatusListener = listener
    return h, nil
}

// OnStart returns an uber/fx Lifecycle hook for startup
func OnStart(logger log.Logger, h health.IHealth) func(context.Context) error {
    return func(_ context.Context) error {
        logger.Log(
            level.Key(), level.InfoValue(),
            xlog.MessageKey(), "health service starting",
        )

        return h.Start()
    }
}

// OnStop returns an uber/fx Lifecycle hook for shutdown
func OnStop(logger log.Logger, h health.IHealth) func(context.Context) error {
    return func(_ context.Context) error {
        logger.Log(
            level.Key(), level.InfoValue(),
            xlog.MessageKey(), "health service stopping",
        )

        err := h.Stop()
        if err == health.ErrAlreadyStopped {
            logger.Log(
                level.Key(), level.InfoValue(),
                xlog.MessageKey(), "health service already stopped or not running",
            )

            return nil
        }

        return err
    }
}