示例#1
0
// New creates a journald logger using the configuration passed in on
// the context.
func New(ctx logger.Context) (logger.Logger, error) {
	if !journal.Enabled() {
		return nil, fmt.Errorf("journald is not enabled on this host")
	}
	// Strip a leading slash so that people can search for
	// CONTAINER_NAME=foo rather than CONTAINER_NAME=/foo.
	name := ctx.ContainerName
	if name[0] == '/' {
		name = name[1:]
	}

	// parse log tag
	tag, err := loggerutils.ParseLogTag(ctx, loggerutils.DefaultTemplate)
	if err != nil {
		return nil, err
	}

	vars := map[string]string{
		"CONTAINER_ID":      ctx.ContainerID[:12],
		"CONTAINER_ID_FULL": ctx.ContainerID,
		"CONTAINER_NAME":    name,
		"CONTAINER_TAG":     tag,
	}
	extraAttrs := ctx.ExtraAttributes(sanitizeKeyMod)
	for k, v := range extraAttrs {
		vars[k] = v
	}
	return &journald{vars: vars, readers: readerList{readers: make(map[*logger.LogWatcher]*logger.LogWatcher)}}, nil
}
示例#2
0
// New creates a new logger that logs to Google Cloud Logging using the application
// default credentials.
//
// See https://developers.google.com/identity/protocols/application-default-credentials
func New(ctx logger.Context) (logger.Logger, error) {
	initGCP()

	var project string
	if projectID != "" {
		project = projectID
	}
	if projectID, found := ctx.Config[projectOptKey]; found {
		project = projectID
	}
	if project == "" {
		return nil, fmt.Errorf("No project was specified and couldn't read project from the meatadata server. Please specify a project")
	}

	c, err := logging.NewClient(context.Background(), project, "gcplogs-docker-driver")
	if err != nil {
		return nil, err
	}

	if err := c.Ping(); err != nil {
		return nil, fmt.Errorf("unable to connect or authenticate with Google Cloud Logging: %v", err)
	}

	l := &gcplogs{
		client: c,
		container: &containerInfo{
			Name:      ctx.ContainerName,
			ID:        ctx.ContainerID,
			ImageName: ctx.ContainerImageName,
			ImageID:   ctx.ContainerImageID,
			Created:   ctx.ContainerCreated,
			Metadata:  ctx.ExtraAttributes(nil),
		},
	}

	if ctx.Config[logCmdKey] == "true" {
		l.container.Command = ctx.Command()
	}

	if onGCE {
		l.instance = &instanceInfo{
			Zone: zone,
			Name: instanceName,
			ID:   instanceID,
		}
	}

	// The logger "overflows" at a rate of 10,000 logs per second and this
	// overflow func is called. We want to surface the error to the user
	// without overly spamming /var/log/docker.log so we log the first time
	// we overflow and every 1000th time after.
	c.Overflow = func(_ *logging.Client, _ logging.Entry) error {
		if i := atomic.AddUint64(&droppedLogs, 1); i%1000 == 1 {
			logrus.Errorf("gcplogs driver has dropped %v logs", i)
		}
		return nil
	}

	return l, nil
}
示例#3
0
// New creates a fluentd logger using the configuration passed in on
// the context. Supported context configuration variables are
// fluentd-address & fluentd-tag.
func New(ctx logger.Context) (logger.Logger, error) {
	host, port, err := parseAddress(ctx.Config["fluentd-address"])
	if err != nil {
		return nil, err
	}

	tag, err := loggerutils.ParseLogTag(ctx, "docker.{{.ID}}")
	if err != nil {
		return nil, err
	}
	extra := ctx.ExtraAttributes(nil)
	logrus.Debugf("logging driver fluentd configured for container:%s, host:%s, port:%d, tag:%s, extra:%v.", ctx.ContainerID, host, port, tag, extra)
	// logger tries to reconnect 2**32 - 1 times
	// failed (and panic) after 204 years [ 1.5 ** (2**32 - 1) - 1 seconds]
	log, err := fluent.New(fluent.Config{FluentPort: port, FluentHost: host, RetryWait: 1000, MaxRetry: math.MaxInt32})
	if err != nil {
		return nil, err
	}
	return &fluentd{
		tag:           tag,
		containerID:   ctx.ContainerID,
		containerName: ctx.ContainerName,
		writer:        log,
		extra:         extra,
	}, nil
}
示例#4
0
// New creates a gelf logger using the configuration passed in on the
// context. Supported context configuration variables are
// gelf-address, & gelf-tag.
func New(ctx logger.Context) (logger.Logger, error) {
	// parse gelf address
	address, err := parseAddress(ctx.Config["gelf-address"])
	if err != nil {
		return nil, err
	}

	// collect extra data for GELF message
	hostname, err := ctx.Hostname()
	if err != nil {
		return nil, fmt.Errorf("gelf: cannot access hostname to set source field")
	}

	// remove trailing slash from container name
	containerName := bytes.TrimLeft([]byte(ctx.ContainerName), "/")

	// parse log tag
	tag, err := loggerutils.ParseLogTag(ctx, "")
	if err != nil {
		return nil, err
	}

	extra := map[string]interface{}{
		"_container_id":   ctx.ContainerID,
		"_container_name": string(containerName),
		"_image_id":       ctx.ContainerImageID,
		"_image_name":     ctx.ContainerImageName,
		"_command":        ctx.Command(),
		"_tag":            tag,
		"_created":        ctx.ContainerCreated,
	}

	extraAttrs := ctx.ExtraAttributes(func(key string) string {
		if key[0] == '_' {
			return key
		}
		return "_" + key
	})
	for k, v := range extraAttrs {
		extra[k] = v
	}

	// create new gelfWriter
	gelfWriter, err := gelf.NewWriter(address)
	if err != nil {
		return nil, fmt.Errorf("gelf: cannot connect to GELF endpoint: %s %v", address, err)
	}

	return &gelfLogger{
		writer:   gelfWriter,
		ctx:      ctx,
		hostname: hostname,
		extra:    extra,
	}, nil
}
示例#5
0
// New creates new JSONFileLogger which writes to filename passed in
// on given context.
func New(ctx logger.Context) (logger.Logger, error) {
	log, err := os.OpenFile(ctx.LogPath, os.O_RDWR|os.O_APPEND|os.O_CREATE, 0600)
	if err != nil {
		return nil, err
	}
	var capval int64 = -1
	if capacity, ok := ctx.Config["max-size"]; ok {
		var err error
		capval, err = units.FromHumanSize(capacity)
		if err != nil {
			return nil, err
		}
	}
	var maxFiles = 1
	if maxFileString, ok := ctx.Config["max-file"]; ok {
		maxFiles, err = strconv.Atoi(maxFileString)
		if err != nil {
			return nil, err
		}
		if maxFiles < 1 {
			return nil, fmt.Errorf("max-file cannot be less than 1")
		}
	}

	var extra []byte
	if attrs := ctx.ExtraAttributes(nil); len(attrs) > 0 {
		var err error
		extra, err = json.Marshal(attrs)
		if err != nil {
			return nil, err
		}
	}

	return &JSONFileLogger{
		f:            log,
		buf:          bytes.NewBuffer(nil),
		ctx:          ctx,
		capacity:     capval,
		n:            maxFiles,
		readers:      make(map[*logger.LogWatcher]struct{}),
		notifyRotate: pubsub.NewPublisher(0, 1),
		extra:        extra,
	}, nil
}
示例#6
0
// New creates new JSONFileLogger which writes to filename passed in
// on given context.
func New(ctx logger.Context) (logger.Logger, error) {
	var capval int64 = -1
	if capacity, ok := ctx.Config["max-size"]; ok {
		var err error
		capval, err = units.FromHumanSize(capacity)
		if err != nil {
			return nil, err
		}
	}
	var maxFiles = 1
	if maxFileString, ok := ctx.Config["max-file"]; ok {
		var err error
		maxFiles, err = strconv.Atoi(maxFileString)
		if err != nil {
			return nil, err
		}
		if maxFiles < 1 {
			return nil, fmt.Errorf("max-file cannot be less than 1")
		}
	}

	writer, err := loggerutils.NewRotateFileWriter(ctx.LogPath, capval, maxFiles)
	if err != nil {
		return nil, err
	}

	var extra []byte
	if attrs := ctx.ExtraAttributes(nil); len(attrs) > 0 {
		var err error
		extra, err = json.Marshal(attrs)
		if err != nil {
			return nil, err
		}
	}

	return &JSONFileLogger{
		buf:           bytes.NewBuffer(nil),
		writer:        writer,
		readers:       make(map[*logger.LogWatcher]struct{}),
		extra:         extra,
		writeNotifier: pubsub.NewPublisher(0, 10),
	}, nil
}
示例#7
0
// New creates a journald logger using the configuration passed in on
// the context.
func New(ctx logger.Context) (logger.Logger, error) {
	if !journal.Enabled() {
		return nil, fmt.Errorf("journald is not enabled on this host")
	}
	// Strip a leading slash so that people can search for
	// CONTAINER_NAME=foo rather than CONTAINER_NAME=/foo.
	name := ctx.ContainerName
	if name[0] == '/' {
		name = name[1:]
	}

	vars := map[string]string{
		"CONTAINER_ID":      ctx.ContainerID[:12],
		"CONTAINER_ID_FULL": ctx.ContainerID,
		"CONTAINER_NAME":    name,
	}
	extraAttrs := ctx.ExtraAttributes(strings.ToTitle)
	for k, v := range extraAttrs {
		vars[k] = v
	}
	return &journald{vars: vars, readers: readerList{readers: make(map[*logger.LogWatcher]*logger.LogWatcher)}}, nil
}
示例#8
0
文件: journald.go 项目: harche/docker
// New creates a journald logger using the configuration passed in on
// the context.
func New(ctx logger.Context) (logger.Logger, error) {
	if !journal.Enabled() {
		return nil, fmt.Errorf("journald is not enabled on this host")
	}

	// parse log tag
	tag, err := loggerutils.ParseLogTag(ctx, loggerutils.DefaultTemplate)
	if err != nil {
		return nil, err
	}

	vars := map[string]string{
		"CONTAINER_ID":      ctx.ContainerID[:12],
		"CONTAINER_ID_FULL": ctx.ContainerID,
		"CONTAINER_NAME":    ctx.Name(),
		"CONTAINER_TAG":     tag,
	}
	extraAttrs := ctx.ExtraAttributes(sanitizeKeyMod)
	for k, v := range extraAttrs {
		vars[k] = v
	}
	return &journald{vars: vars, readers: readerList{readers: make(map[*logger.LogWatcher]*logger.LogWatcher)}}, nil
}
示例#9
0
// New creates a fluentd logger using the configuration passed in on
// the context. Supported context configuration variables are
// fluentd-address & fluentd-tag.
func New(ctx logger.Context) (logger.Logger, error) {
	host, port, err := parseAddress(ctx.Config["fluentd-address"])
	if err != nil {
		return nil, err
	}

	tag, err := loggerutils.ParseLogTag(ctx, "docker.{{.ID}}")
	if err != nil {
		return nil, err
	}
	failOnStartupError, err := loggerutils.ParseFailOnStartupErrorFlag(ctx)
	if err != nil {
		return nil, err
	}
	bufferLimit, err := parseBufferLimit(ctx.Config["buffer-limit"])
	if err != nil {
		return nil, err
	}
	extra := ctx.ExtraAttributes(nil)
	logrus.Debugf("logging driver fluentd configured for container:%s, host:%s, port:%d, tag:%s, extra:%v.", ctx.ContainerID, host, port, tag, extra)
	// logger tries to reconnect 2**32 - 1 times
	// failed (and panic) after 204 years [ 1.5 ** (2**32 - 1) - 1 seconds]
	log, err := fluent.New(fluent.Config{FluentPort: port, FluentHost: host, RetryWait: 1000, MaxRetry: math.MaxInt32, BufferLimit: bufferLimit})
	if err != nil {
		if failOnStartupError {
			return nil, err
		}
		logrus.Warnf("fluentd cannot connect to configured endpoint. Ignoring as instructed. Error: %q", err)
	}
	return &fluentd{
		tag:           tag,
		containerID:   ctx.ContainerID,
		containerName: ctx.ContainerName,
		writer:        log,
		extra:         extra,
	}, nil
}
示例#10
0
文件: gelf.go 项目: harche/docker
// New creates a gelf logger using the configuration passed in on the
// context. The supported context configuration variable is gelf-address.
func New(ctx logger.Context) (logger.Logger, error) {
	// parse gelf address
	address, err := parseAddress(ctx.Config["gelf-address"])
	if err != nil {
		return nil, err
	}

	// collect extra data for GELF message
	hostname, err := ctx.Hostname()
	if err != nil {
		return nil, fmt.Errorf("gelf: cannot access hostname to set source field")
	}

	// parse log tag
	tag, err := loggerutils.ParseLogTag(ctx, loggerutils.DefaultTemplate)
	if err != nil {
		return nil, err
	}

	extra := map[string]interface{}{
		"_container_id":   ctx.ContainerID,
		"_container_name": ctx.Name(),
		"_image_id":       ctx.ContainerImageID,
		"_image_name":     ctx.ContainerImageName,
		"_command":        ctx.Command(),
		"_tag":            tag,
		"_created":        ctx.ContainerCreated,
	}

	extraAttrs := ctx.ExtraAttributes(func(key string) string {
		if key[0] == '_' {
			return key
		}
		return "_" + key
	})
	for k, v := range extraAttrs {
		extra[k] = v
	}

	rawExtra, err := json.Marshal(extra)
	if err != nil {
		return nil, err
	}

	// create new gelfWriter
	gelfWriter, err := gelf.NewWriter(address)
	if err != nil {
		return nil, fmt.Errorf("gelf: cannot connect to GELF endpoint: %s %v", address, err)
	}

	if v, ok := ctx.Config["gelf-compression-type"]; ok {
		switch v {
		case "gzip":
			gelfWriter.CompressionType = gelf.CompressGzip
		case "zlib":
			gelfWriter.CompressionType = gelf.CompressZlib
		case "none":
			gelfWriter.CompressionType = gelf.CompressNone
		default:
			return nil, fmt.Errorf("gelf: invalid compression type %q", v)
		}
	}

	if v, ok := ctx.Config["gelf-compression-level"]; ok {
		val, err := strconv.Atoi(v)
		if err != nil {
			return nil, fmt.Errorf("gelf: invalid compression level %s, err %v", v, err)
		}
		gelfWriter.CompressionLevel = val
	}

	return &gelfLogger{
		writer:   gelfWriter,
		ctx:      ctx,
		hostname: hostname,
		rawExtra: rawExtra,
	}, nil
}
示例#11
0
// New creates splunk logger driver using configuration passed in context
func New(ctx logger.Context) (logger.Logger, error) {
	hostname, err := ctx.Hostname()
	if err != nil {
		return nil, fmt.Errorf("%s: cannot access hostname to set source field", driverName)
	}

	// Parse and validate Splunk URL
	splunkURL, err := parseURL(ctx)
	if err != nil {
		return nil, err
	}

	// Splunk Token is required parameter
	splunkToken, ok := ctx.Config[splunkTokenKey]
	if !ok {
		return nil, fmt.Errorf("%s: %s is expected", driverName, splunkTokenKey)
	}

	tlsConfig := &tls.Config{}

	// Splunk is using autogenerated certificates by default,
	// allow users to trust them with skipping verification
	if insecureSkipVerifyStr, ok := ctx.Config[splunkInsecureSkipVerifyKey]; ok {
		insecureSkipVerify, err := strconv.ParseBool(insecureSkipVerifyStr)
		if err != nil {
			return nil, err
		}
		tlsConfig.InsecureSkipVerify = insecureSkipVerify
	}

	// If path to the root certificate is provided - load it
	if caPath, ok := ctx.Config[splunkCAPathKey]; ok {
		caCert, err := ioutil.ReadFile(caPath)
		if err != nil {
			return nil, err
		}
		caPool := x509.NewCertPool()
		caPool.AppendCertsFromPEM(caCert)
		tlsConfig.RootCAs = caPool
	}

	if caName, ok := ctx.Config[splunkCANameKey]; ok {
		tlsConfig.ServerName = caName
	}

	transport := &http.Transport{
		TLSClientConfig: tlsConfig,
	}
	client := &http.Client{
		Transport: transport,
	}

	var nullMessage = &splunkMessage{
		Host: hostname,
	}

	// Optional parameters for messages
	nullMessage.Source = ctx.Config[splunkSourceKey]
	nullMessage.SourceType = ctx.Config[splunkSourceTypeKey]
	nullMessage.Index = ctx.Config[splunkIndexKey]

	tag, err := loggerutils.ParseLogTag(ctx, "{{.ID}}")
	if err != nil {
		return nil, err
	}
	nullMessage.Event.Tag = tag
	nullMessage.Event.Attrs = ctx.ExtraAttributes(nil)

	logger := &splunkLogger{
		client:      client,
		transport:   transport,
		url:         splunkURL.String(),
		auth:        "Splunk " + splunkToken,
		nullMessage: nullMessage,
	}

	err = verifySplunkConnection(logger)
	if err != nil {
		return nil, err
	}

	return logger, nil
}
示例#12
0
// New creates a fluentd logger using the configuration passed in on
// the context. The supported context configuration variable is
// fluentd-address.
func New(ctx logger.Context) (logger.Logger, error) {
	loc, err := parseAddress(ctx.Config[addressKey])
	if err != nil {
		return nil, err
	}

	tag, err := loggerutils.ParseLogTag(ctx, loggerutils.DefaultTemplate)
	if err != nil {
		return nil, err
	}

	extra := ctx.ExtraAttributes(nil)

	bufferLimit := defaultBufferLimit
	if ctx.Config[bufferLimitKey] != "" {
		bl64, err := units.RAMInBytes(ctx.Config[bufferLimitKey])
		if err != nil {
			return nil, err
		}
		bufferLimit = int(bl64)
	}

	retryWait := defaultRetryWait
	if ctx.Config[retryWaitKey] != "" {
		rwd, err := time.ParseDuration(ctx.Config[retryWaitKey])
		if err != nil {
			return nil, err
		}
		retryWait = int(rwd.Seconds() * 1000)
	}

	maxRetries := defaultMaxRetries
	if ctx.Config[maxRetriesKey] != "" {
		mr64, err := strconv.ParseUint(ctx.Config[maxRetriesKey], 10, strconv.IntSize)
		if err != nil {
			return nil, err
		}
		maxRetries = int(mr64)
	}

	asyncConnect := false
	if ctx.Config[asyncConnectKey] != "" {
		if asyncConnect, err = strconv.ParseBool(ctx.Config[asyncConnectKey]); err != nil {
			return nil, err
		}
	}

	fluentConfig := fluent.Config{
		FluentPort:       loc.port,
		FluentHost:       loc.host,
		FluentNetwork:    loc.protocol,
		FluentSocketPath: loc.path,
		BufferLimit:      bufferLimit,
		RetryWait:        retryWait,
		MaxRetry:         maxRetries,
		AsyncConnect:     asyncConnect,
	}

	logrus.WithField("container", ctx.ContainerID).WithField("config", fluentConfig).
		Debug("logging driver fluentd configured")

	log, err := fluent.New(fluentConfig)
	if err != nil {
		return nil, err
	}
	return &fluentd{
		tag:           tag,
		containerID:   ctx.ContainerID,
		containerName: ctx.ContainerName,
		writer:        log,
		extra:         extra,
	}, nil
}
示例#13
0
文件: splunk.go 项目: HuKeping/docker
// New creates splunk logger driver using configuration passed in context
func New(ctx logger.Context) (logger.Logger, error) {
	hostname, err := ctx.Hostname()
	if err != nil {
		return nil, fmt.Errorf("%s: cannot access hostname to set source field", driverName)
	}

	// Parse and validate Splunk URL
	splunkURL, err := parseURL(ctx)
	if err != nil {
		return nil, err
	}

	// Splunk Token is required parameter
	splunkToken, ok := ctx.Config[splunkTokenKey]
	if !ok {
		return nil, fmt.Errorf("%s: %s is expected", driverName, splunkTokenKey)
	}

	tlsConfig := &tls.Config{}

	// Splunk is using autogenerated certificates by default,
	// allow users to trust them with skipping verification
	if insecureSkipVerifyStr, ok := ctx.Config[splunkInsecureSkipVerifyKey]; ok {
		insecureSkipVerify, err := strconv.ParseBool(insecureSkipVerifyStr)
		if err != nil {
			return nil, err
		}
		tlsConfig.InsecureSkipVerify = insecureSkipVerify
	}

	// If path to the root certificate is provided - load it
	if caPath, ok := ctx.Config[splunkCAPathKey]; ok {
		caCert, err := ioutil.ReadFile(caPath)
		if err != nil {
			return nil, err
		}
		caPool := x509.NewCertPool()
		caPool.AppendCertsFromPEM(caCert)
		tlsConfig.RootCAs = caPool
	}

	if caName, ok := ctx.Config[splunkCANameKey]; ok {
		tlsConfig.ServerName = caName
	}

	transport := &http.Transport{
		TLSClientConfig: tlsConfig,
	}
	client := &http.Client{
		Transport: transport,
	}

	source := ctx.Config[splunkSourceKey]
	sourceType := ctx.Config[splunkSourceTypeKey]
	index := ctx.Config[splunkIndexKey]

	var nullMessage = &splunkMessage{
		Host:       hostname,
		Source:     source,
		SourceType: sourceType,
		Index:      index,
	}

	tag, err := loggerutils.ParseLogTag(ctx, loggerutils.DefaultTemplate)
	if err != nil {
		return nil, err
	}

	attrs := ctx.ExtraAttributes(nil)

	logger := &splunkLogger{
		client:      client,
		transport:   transport,
		url:         splunkURL.String(),
		auth:        "Splunk " + splunkToken,
		nullMessage: nullMessage,
	}

	// By default we verify connection, but we allow use to skip that
	verifyConnection := true
	if verifyConnectionStr, ok := ctx.Config[splunkVerifyConnectionKey]; ok {
		var err error
		verifyConnection, err = strconv.ParseBool(verifyConnectionStr)
		if err != nil {
			return nil, err
		}
	}
	if verifyConnection {
		err = verifySplunkConnection(logger)
		if err != nil {
			return nil, err
		}
	}

	var splunkFormat string
	if splunkFormatParsed, ok := ctx.Config[splunkFormatKey]; ok {
		switch splunkFormatParsed {
		case splunkFormatInline:
		case splunkFormatJSON:
		case splunkFormatRaw:
		default:
			return nil, fmt.Errorf("Unknown format specified %s, supported formats are inline, json and raw", splunkFormat)
		}
		splunkFormat = splunkFormatParsed
	} else {
		splunkFormat = splunkFormatInline
	}

	switch splunkFormat {
	case splunkFormatInline:
		nullEvent := &splunkMessageEvent{
			Tag:   tag,
			Attrs: attrs,
		}

		return &splunkLoggerInline{logger, nullEvent}, nil
	case splunkFormatJSON:
		nullEvent := &splunkMessageEvent{
			Tag:   tag,
			Attrs: attrs,
		}

		return &splunkLoggerJSON{&splunkLoggerInline{logger, nullEvent}}, nil
	case splunkFormatRaw:
		var prefix bytes.Buffer
		prefix.WriteString(tag)
		prefix.WriteString(" ")
		for key, value := range attrs {
			prefix.WriteString(key)
			prefix.WriteString("=")
			prefix.WriteString(value)
			prefix.WriteString(" ")
		}

		return &splunkLoggerRaw{logger, prefix.Bytes()}, nil
	default:
		return nil, fmt.Errorf("Unexpected format %s", splunkFormat)
	}
}
示例#14
0
// New creates splunk logger driver using configuration passed in context
func New(ctx logger.Context) (logger.Logger, error) {
	hostname, err := ctx.Hostname()
	if err != nil {
		return nil, fmt.Errorf("%s: cannot access hostname to set source field", driverName)
	}

	// Parse and validate Splunk URL
	splunkURL, err := parseURL(ctx)
	if err != nil {
		return nil, err
	}

	// Splunk Token is required parameter
	splunkToken, ok := ctx.Config[splunkTokenKey]
	if !ok {
		return nil, fmt.Errorf("%s: %s is expected", driverName, splunkTokenKey)
	}

	tlsConfig := &tls.Config{}

	// Splunk is using autogenerated certificates by default,
	// allow users to trust them with skipping verification
	if insecureSkipVerifyStr, ok := ctx.Config[splunkInsecureSkipVerifyKey]; ok {
		insecureSkipVerify, err := strconv.ParseBool(insecureSkipVerifyStr)
		if err != nil {
			return nil, err
		}
		tlsConfig.InsecureSkipVerify = insecureSkipVerify
	}

	// If path to the root certificate is provided - load it
	if caPath, ok := ctx.Config[splunkCAPathKey]; ok {
		caCert, err := ioutil.ReadFile(caPath)
		if err != nil {
			return nil, err
		}
		caPool := x509.NewCertPool()
		caPool.AppendCertsFromPEM(caCert)
		tlsConfig.RootCAs = caPool
	}

	if caName, ok := ctx.Config[splunkCANameKey]; ok {
		tlsConfig.ServerName = caName
	}

	gzipCompression := false
	if gzipCompressionStr, ok := ctx.Config[splunkGzipCompressionKey]; ok {
		gzipCompression, err = strconv.ParseBool(gzipCompressionStr)
		if err != nil {
			return nil, err
		}
	}

	gzipCompressionLevel := gzip.DefaultCompression
	if gzipCompressionLevelStr, ok := ctx.Config[splunkGzipCompressionLevelKey]; ok {
		var err error
		gzipCompressionLevel64, err := strconv.ParseInt(gzipCompressionLevelStr, 10, 32)
		if err != nil {
			return nil, err
		}
		gzipCompressionLevel = int(gzipCompressionLevel64)
		if gzipCompressionLevel < gzip.DefaultCompression || gzipCompressionLevel > gzip.BestCompression {
			err := fmt.Errorf("Not supported level '%s' for %s (supported values between %d and %d).",
				gzipCompressionLevelStr, splunkGzipCompressionLevelKey, gzip.DefaultCompression, gzip.BestCompression)
			return nil, err
		}
	}

	transport := &http.Transport{
		TLSClientConfig: tlsConfig,
	}
	client := &http.Client{
		Transport: transport,
	}

	source := ctx.Config[splunkSourceKey]
	sourceType := ctx.Config[splunkSourceTypeKey]
	index := ctx.Config[splunkIndexKey]

	var nullMessage = &splunkMessage{
		Host:       hostname,
		Source:     source,
		SourceType: sourceType,
		Index:      index,
	}

	// Allow user to remove tag from the messages by setting tag to empty string
	tag := ""
	if tagTemplate, ok := ctx.Config[tagKey]; !ok || tagTemplate != "" {
		tag, err = loggerutils.ParseLogTag(ctx, loggerutils.DefaultTemplate)
		if err != nil {
			return nil, err
		}
	}

	attrs := ctx.ExtraAttributes(nil)

	var (
		postMessagesFrequency = getAdvancedOptionDuration(envVarPostMessagesFrequency, defaultPostMessagesFrequency)
		postMessagesBatchSize = getAdvancedOptionInt(envVarPostMessagesBatchSize, defaultPostMessagesBatchSize)
		bufferMaximum         = getAdvancedOptionInt(envVarBufferMaximum, defaultBufferMaximum)
		streamChannelSize     = getAdvancedOptionInt(envVarStreamChannelSize, defaultStreamChannelSize)
	)

	logger := &splunkLogger{
		client:                client,
		transport:             transport,
		url:                   splunkURL.String(),
		auth:                  "Splunk " + splunkToken,
		nullMessage:           nullMessage,
		gzipCompression:       gzipCompression,
		gzipCompressionLevel:  gzipCompressionLevel,
		stream:                make(chan *splunkMessage, streamChannelSize),
		postMessagesFrequency: postMessagesFrequency,
		postMessagesBatchSize: postMessagesBatchSize,
		bufferMaximum:         bufferMaximum,
	}

	// By default we verify connection, but we allow use to skip that
	verifyConnection := true
	if verifyConnectionStr, ok := ctx.Config[splunkVerifyConnectionKey]; ok {
		var err error
		verifyConnection, err = strconv.ParseBool(verifyConnectionStr)
		if err != nil {
			return nil, err
		}
	}
	if verifyConnection {
		err = verifySplunkConnection(logger)
		if err != nil {
			return nil, err
		}
	}

	var splunkFormat string
	if splunkFormatParsed, ok := ctx.Config[splunkFormatKey]; ok {
		switch splunkFormatParsed {
		case splunkFormatInline:
		case splunkFormatJSON:
		case splunkFormatRaw:
		default:
			return nil, fmt.Errorf("Unknown format specified %s, supported formats are inline, json and raw", splunkFormat)
		}
		splunkFormat = splunkFormatParsed
	} else {
		splunkFormat = splunkFormatInline
	}

	var loggerWrapper splunkLoggerInterface

	switch splunkFormat {
	case splunkFormatInline:
		nullEvent := &splunkMessageEvent{
			Tag:   tag,
			Attrs: attrs,
		}

		loggerWrapper = &splunkLoggerInline{logger, nullEvent}
	case splunkFormatJSON:
		nullEvent := &splunkMessageEvent{
			Tag:   tag,
			Attrs: attrs,
		}

		loggerWrapper = &splunkLoggerJSON{&splunkLoggerInline{logger, nullEvent}}
	case splunkFormatRaw:
		var prefix bytes.Buffer
		if tag != "" {
			prefix.WriteString(tag)
			prefix.WriteString(" ")
		}
		for key, value := range attrs {
			prefix.WriteString(key)
			prefix.WriteString("=")
			prefix.WriteString(value)
			prefix.WriteString(" ")
		}

		loggerWrapper = &splunkLoggerRaw{logger, prefix.Bytes()}
	default:
		return nil, fmt.Errorf("Unexpected format %s", splunkFormat)
	}

	go loggerWrapper.worker()

	return loggerWrapper, nil
}