Switch from built-in logger to logrus

Dockerfile

@@ -10,7 +10,7 @@ FROM gliderlabs/logspout:${LOGSPOUT_VERSION} as logspout
 #
 # Build stage, build logspout with fluentd adapter
 #
-FROM golang:1.12.5-alpine3.9 as builder
+FROM golang:1.20.3-alpine3.17 as builder
 RUN apk add --update go build-base git mercurial ca-certificates git
 ENV GO111MODULE=on
 WORKDIR /go/src/github.com/gliderlabs/logspout
@@ -20,6 +20,7 @@ ADD . /go/src/github.com/dsouzajude/logspout-fluentd
 RUN cd /go/src/github.com/dsouzajude/logspout-fluentd; go mod download
 RUN cd /go/src/github.com/gliderlabs/logspout; go mod download
 RUN echo "replace github.com/dsouzajude/logspout-fluentd => /go/src/github.com/dsouzajude/logspout-fluentd" >> go.mod
+RUN go mod tidy
 RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -ldflags "-X main.Version=$1" -o /bin/logspout
 
 

Readme.md

@@ -28,6 +28,7 @@ Optional environment variables:
 
 - `TAG_PREFIX` the *fixed* tag prefix
 - `TAG_SUFFIX_LABEL` the docker label key for which to substitue as the *dynamic* tag suffix
+- `LOG_LEVEL` [trace|debug|info|warning|error|fatal|panic] Change the log level. Defaults to info.
 
 The other fluentd specific environment variables include the list below and
 their explanation can be better read from the fluentd log driver [website](https://docs.docker.com/config/containers/logging/fluentd/).
@@ -40,7 +41,6 @@ their explanation can be better read from the fluentd log driver [website](https
 - `FLUENTD_REQUEST_ACK` [true|false] For reliability. Fluent-bit currently doesn't support this. Defaults to false.
 - `FLUENTD_WRITE_TIMEOUT` [int] Write timeout to post to fluentd/fluent-bit. Defaults to 3 seconds.
 
-
 Configure Logspout to receive forwarded messages, something like this:
 
 ```
@@ -82,9 +82,19 @@ Configure Logspout to receive forwarded messages, something like this:
 
 # Run standalone fluent-bit instance
 >> docker run -ti -p 24224:24224 \
-        fluent/fluent-bit:1.2 /fluent-bit/bin/fluent-bit \
-            -i forward://0.0.0.0:24224 -o stdout
+        fluent/fluent-bit:2.0.11 /fluent-bit/bin/fluent-bit \
+            -i forward -o stdout
 
+# Run custom built of logspout locally:
+>> docker run --rm --name="logspout" --network host \
+			-v /var/run/docker.sock:/var/run/docker.sock \
+			-e TAG_PREFIX=docker \
+			-e TAG_SUFFIX_LABEL="com.mycompany.service" \
+			-e LOG_LEVEL="debug" \
+			-e FLUENTD_ASYNC_CONNECT="true" \
+			-e LOGSPOUT="ignore" \
+			mycustomlogspout \
+				./logspout fluentd://localhost:24224
 
 # Send sample log from test container, you should view the log entry
 # captured in logspout and a similar log entry in fluent-bit.

fluentd/adapter.go

@@ -19,14 +19,16 @@ command after building:
 *
 */
 import (
-	"log"
 	"math"
 	"net"
 	"os"
 	"regexp"
 	"strconv"
 	"time"
 
+	log "github.com/sirupsen/logrus"
+	easy "github.com/t-tomalak/logrus-easy-formatter"
+
 	"github.com/fluent/fluent-logger-golang/fluent"
 	"github.com/gliderlabs/logspout/router"
 	"github.com/pkg/errors"
@@ -58,11 +60,15 @@ type Adapter struct {
 
 // Stream handles a stream of messages from Logspout. Implements router.logAdapter.
 func (ad *Adapter) Stream(logstream chan *router.Message) {
+	// create a regex pattern to identify empty messages
+	pattern, err := regexp.Compile("^[[:space:]]*$")
+	if err != nil {
+		log.Fatalf("Could not compile regexp: %v", err)
+	}
 	for message := range logstream {
 		// Skip if message is empty
-		messageIsEmpty, err := regexp.MatchString("^[[:space:]]*$", message.Data)
-		if messageIsEmpty {
-			log.Println("Skipping empty message!")
+		if pattern.MatchString(message.Data) {
+			log.Debug("Skipping empty message!")
 			continue
 		}
 
@@ -84,12 +90,12 @@ func (ad *Adapter) Stream(logstream chan *router.Message) {
 			"container_name": message.Container.Name,
 			"source":         message.Source,
 		}
-		log.Println(tag, message.Time, record)
+		log.Debugf("tag=%s; record=%s", tag, record)
 
 		// Send to fluentd
 		err = ad.writer.PostWithTime(tag, message.Time, record)
 		if err != nil {
-			log.Println("fluentd-adapter PostWithTime Error: ", err)
+			log.Errorf("fluentd-adapter PostWithTime Error: %v", err)
 			continue
 		}
 	}
@@ -105,15 +111,19 @@ func NewAdapter(route *router.Route) (router.LogAdapter, error) {
 	if err != nil {
 		return nil, err
 	}
-	log.Println("Connectivity successful to fluentd @ " + route.Address)
+	log.Infof("Connectivity successful to fluentd @ %s", route.Address)
 
 	// Construct fluentd config object
 	host, port, err := net.SplitHostPort(route.Address)
-	portNum, err := strconv.Atoi(port)
 	if err != nil {
 		return nil, errors.Wrapf(err, "Invalid fluentd-address %s", route.Address)
 	}
 
+	portNum, err := strconv.Atoi(port)
+	if err != nil {
+		return nil, errors.Wrapf(err, "Invalid port number in fluentd-address %s", route.Address)
+	}
+
 	bufferLimit, err := strconv.Atoi(getenv("FLUENTD_BUFFER_LIMIT", strconv.Itoa(defaultBufferLimit)))
 	if err != nil {
 		return nil, err
@@ -179,5 +189,18 @@ func NewAdapter(route *router.Route) (router.LogAdapter, error) {
 }
 
 func init() {
+	logLevel, err := log.ParseLevel(getenv("LOG_LEVEL", "info"))
+	if err != nil {
+		log.Fatalf("Error parsing log level: %v", err)
+	}
+	log.SetFormatter(
+		&easy.Formatter{
+			TimestampFormat: "2006-01-02 15:04:05",
+			LogFormat:       "%time% [%lvl%] %msg%\n",
+		},
+	)
+	log.SetLevel(logLevel)
+	log.Infof("LOG_LEVEL=%s", logLevel)
+
 	router.AdapterFactories.Register(NewAdapter, "fluentd")
 }

go.mod

@@ -1,16 +1,44 @@
 module github.com/dsouzajude/logspout-fluentd
 
-go 1.12
+go 1.20
 
 require (
-	github.com/Sirupsen/logrus v0.10.1-0.20160601113210-f3cfb454f4c2 // indirect
-	github.com/bmizerany/assert v0.0.0-20160611221934-b7ed37b82869 // indirect
 	github.com/fluent/fluent-logger-golang v1.4.0
 	github.com/fsouza/go-dockerclient v1.6.0
 	github.com/gliderlabs/logspout v3.2.6+incompatible
-	github.com/kr/pretty v0.2.0 // indirect
-	github.com/philhofer/fwd v1.0.0 // indirect
 	github.com/pkg/errors v0.8.1
+	github.com/sirupsen/logrus v1.8.1
 	github.com/stretchr/testify v1.4.0
-	github.com/tinylib/msgp v1.1.1 // indirect
+	github.com/t-tomalak/logrus-easy-formatter v0.0.0-20190827215021-c074f06c5816
+)
+
+require (
+	github.com/Azure/go-ansiterm v0.0.0-20170929234023-d6e3b3328b78 // indirect
+	github.com/Microsoft/go-winio v0.4.15-0.20190919025122-fc70bd9a86b5 // indirect
+	github.com/Microsoft/hcsshim v0.8.7-0.20191101173118-65519b62243c // indirect
+	github.com/bmizerany/assert v0.0.0-20160611221934-b7ed37b82869 // indirect
+	github.com/containerd/containerd v1.3.0 // indirect
+	github.com/containerd/continuity v0.0.0-20190426062206-aaeac12a7ffc // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/docker/distribution v2.7.1+incompatible // indirect
+	github.com/docker/docker v1.4.2-0.20191101170500-ac7306503d23 // indirect
+	github.com/docker/go-connections v0.4.0 // indirect
+	github.com/docker/go-units v0.4.0 // indirect
+	github.com/gogo/protobuf v1.2.1 // indirect
+	github.com/golang/protobuf v1.3.1 // indirect
+	github.com/gorilla/mux v1.7.3 // indirect
+	github.com/kr/pretty v0.3.1 // indirect
+	github.com/morikuni/aec v0.0.0-20170113033406-39771216ff4c // indirect
+	github.com/opencontainers/go-digest v1.0.0-rc1 // indirect
+	github.com/opencontainers/image-spec v1.0.1 // indirect
+	github.com/opencontainers/runc v1.1.6 // indirect
+	github.com/philhofer/fwd v1.1.2 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/tinylib/msgp v1.1.8 // indirect
+	golang.org/x/net v0.8.0 // indirect
+	golang.org/x/sync v0.1.0 // indirect
+	golang.org/x/sys v0.6.0 // indirect
+	google.golang.org/genproto v0.0.0-20190425155659-357c62f0e4bb // indirect
+	google.golang.org/grpc v1.22.0 // indirect
+	gopkg.in/yaml.v2 v2.2.2 // indirect
 )