Add option for logging in JSON format

THIRD_PARTY_LICENSES

@@ -414,3 +414,29 @@ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+------
+
+** github.com/rs/zerolog; version v1.18.0 --
+
+MIT License
+
+Copyright (c) 2017 Olivier Poitrey
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

cmd/node-termination-handler.go

@@ -15,7 +15,6 @@ package main
 
 import (
 	"fmt"
-	"log"
 	"os"
 	"os/signal"
 	"syscall"
@@ -27,6 +26,8 @@ import (
 	"github.com/aws/aws-node-termination-handler/pkg/interruptioneventstore"
 	"github.com/aws/aws-node-termination-handler/pkg/node"
 	"github.com/aws/aws-node-termination-handler/pkg/webhook"
+	"github.com/rs/zerolog"
+	"github.com/rs/zerolog/log"
 )
 
 const (
@@ -37,22 +38,29 @@ const (
 type monitorFunc func(chan<- interruptionevent.InterruptionEvent, chan<- interruptionevent.InterruptionEvent, *ec2metadata.Service) error
 
 func main() {
+	// Zerolog uses json formatting by default, so change that to a human-readable format instead
+	log.Logger = log.Output(zerolog.ConsoleWriter{Out: os.Stderr, TimeFormat: time.RFC3339, NoColor: true})
+
 	signalChan := make(chan os.Signal, 1)
 	signal.Notify(signalChan, syscall.SIGTERM)
 	defer signal.Stop(signalChan)
 
 	nthConfig, err := config.ParseCliArgs()
 	if err != nil {
-		log.Fatalln("Failed to parse cli args: ", err)
+		log.Fatal().Err(err).Msg("Failed to parse cli args,")
 	}
 
 	err = webhook.ValidateWebhookConfig(nthConfig)
 	if err != nil {
-		log.Fatalln("Webhook validation failed: ", err)
+		log.Fatal().Err(err).Msg("Webhook validation failed,")
 	}
 	node, err := node.New(nthConfig)
 	if err != nil {
-		log.Fatalln("Unable to instantiate a node for various kubernetes node functions: ", err)
+		log.Fatal().Err(err).Msg("Unable to instantiate a node for various kubernetes node functions,")
+	}
+
+	if nthConfig.JsonLogging {
+		log.Logger = zerolog.New(os.Stderr).With().Timestamp().Logger()
 	}
 
 	imds := ec2metadata.New(nthConfig.MetadataURL, nthConfig.MetadataTries)
@@ -63,7 +71,7 @@ func main() {
 	if nthConfig.EnableScheduledEventDraining {
 		err = handleRebootUncordon(interruptionEventStore, *node)
 		if err != nil {
-			log.Printf("Unable to complete the uncordon after reboot workflow on startup: %v\n", err)
+			log.Printf("Unable to complete the uncordon after reboot workflow on startup: %v", err)
 		}
 	}
 
@@ -93,11 +101,11 @@ func main() {
 	}
 
 	go watchForInterruptionEvents(interruptionChan, interruptionEventStore, nodeMetadata)
-	log.Println("Started watching for interruption events")
-	log.Println("Kubernetes AWS Node Termination Handler has started successfully!")
+	log.Print("Started watching for interruption events")
+	log.Print("Kubernetes AWS Node Termination Handler has started successfully!")
 
 	go watchForCancellationEvents(cancelChan, interruptionEventStore, node, nodeMetadata)
-	log.Println("Started watching for event cancellations")
+	log.Print("Started watching for event cancellations")
 
 	for range time.NewTicker(1 * time.Second).C {
 		select {
@@ -108,7 +116,7 @@ func main() {
 			drainOrCordonIfNecessary(interruptionEventStore, *node, nthConfig, nodeMetadata)
 		}
 	}
-	log.Println("AWS Node Termination Handler is shutting down")
+	log.Print("AWS Node Termination Handler is shutting down")
 }
 
 func handleRebootUncordon(interruptionEventStore *interruptioneventstore.Store, node node.Node) error {
@@ -134,25 +142,25 @@ func handleRebootUncordon(interruptionEventStore *interruptioneventstore.Store,
 func watchForInterruptionEvents(interruptionChan <-chan interruptionevent.InterruptionEvent, interruptionEventStore *interruptioneventstore.Store, nodeMetadata ec2metadata.NodeMetadata) {
 	for {
 		interruptionEvent := <-interruptionChan
-		log.Printf("Got interruption event from channel %+v %+v\n", nodeMetadata, interruptionEvent)
+		log.Printf("Got interruption event from channel %+v %+v", nodeMetadata, interruptionEvent)
 		interruptionEventStore.AddInterruptionEvent(&interruptionEvent)
 	}
 }
 
 func watchForCancellationEvents(cancelChan <-chan interruptionevent.InterruptionEvent, interruptionEventStore *interruptioneventstore.Store, node *node.Node, nodeMetadata ec2metadata.NodeMetadata) {
 	for {
 		interruptionEvent := <-cancelChan
-		log.Printf("Got cancel event from channel %+v %+v\n", nodeMetadata, interruptionEvent)
+		log.Printf("Got cancel event from channel %+v %+v", nodeMetadata, interruptionEvent)
 		interruptionEventStore.CancelInterruptionEvent(interruptionEvent.EventID)
 		if interruptionEventStore.ShouldUncordonNode() {
-			log.Println("Uncordoning the node due to a cancellation event")
+			log.Print("Uncordoning the node due to a cancellation event")
 			err := node.Uncordon()
 			if err != nil {
 				log.Printf("Uncordoning the node failed: %v", err)
 			}
 			node.RemoveNTHLabels()
 		} else {
-			log.Println("Another interruption event is active, not uncordoning the node")
+			log.Print("Another interruption event is active, not uncordoning the node")
 		}
 	}
 }
@@ -162,23 +170,23 @@ func drainOrCordonIfNecessary(interruptionEventStore *interruptioneventstore.Sto
 		if drainEvent.PreDrainTask != nil {
 			err := drainEvent.PreDrainTask(*drainEvent, node)
 			if err != nil {
-				log.Println("There was a problem executing the pre-drain task: ", err)
+				log.Printf("There was a problem executing the pre-drain task: %v", err)
 			}
 		}
 		if nthConfig.CordonOnly {
 			err := node.Cordon()
 			if err != nil {
-				log.Println("There was a problem while trying to cordon the node: ", err)
+				log.Printf("There was a problem while trying to cordon the node: %v", err)
 				os.Exit(1)
 			}
-			log.Printf("Node %q successfully cordoned.\n", nthConfig.NodeName)
+			log.Printf("Node %q successfully cordoned.", nthConfig.NodeName)
 		} else {
 			err := node.CordonAndDrain()
 			if err != nil {
-				log.Println("There was a problem while trying to cordon and drain the node: ", err)
+				log.Printf("There was a problem while trying to cordon and drain the node: %v", err)
 				os.Exit(1)
 			}
-			log.Printf("Node %q successfully cordoned and drained.\n", nthConfig.NodeName)
+			log.Printf("Node %q successfully cordoned and drained.", nthConfig.NodeName)
 		}
 		interruptionEventStore.MarkAllAsDrained()
 		if nthConfig.WebhookURL != "" {

config/helm/aws-node-termination-handler/README.md

@@ -67,6 +67,7 @@ Parameter | Description | Default
 `enableSpotInterruptionDraining` | If true, drain nodes when the spot interruption termination notice is received | `true`
 `metadataTries` | The number of times to try requesting metadata. If you would like 2 retries, set metadata-tries to 3. | `3`
 `cordonOnly` | If true, nodes will be cordoned but not drained when an interruption event occurs. | `false`
+`jsonLogging` | If true, use JSON-formatted logs instead of human readable logs. | `false`
 `affinity` | node/pod affinities | None
 `podAnnotations` | annotations to add to each pod | `{}`
 `priorityClassName` | Name of the priorityClass | `system-node-critical`

config/helm/aws-node-termination-handler/templates/daemonset.yaml

@@ -109,6 +109,8 @@ spec:
             value: {{ .Values.metadataTries | quote }}
           - name: CORDON_ONLY
             value: {{ .Values.cordonOnly | quote }}
+          - name: JSON_LOGGING
+            value: {{ .Values.jsonLogging | quote }}
           resources:
             {{- toYaml .Values.resources | nindent 12 }}
       {{- with .Values.nodeSelector }}

go.mod

@@ -3,6 +3,7 @@ module github.com/aws/aws-node-termination-handler
 go 1.14
 
 require (
+	github.com/rs/zerolog v1.18.0
 	golang.org/x/time v0.0.0-20190921001708-c4c64cad1fd0 // indirect
 	k8s.io/api v0.0.0-20191010143144-fbf594f18f80
 	k8s.io/apimachinery v0.0.0-20191016060620-86f2f1b9c076

go.sum

@@ -30,6 +30,7 @@ github.com/client9/misspell v0.3.4/go.mod h1:qj6jICC3Q7zFZvVWo7KLAzC3yx5G7kyvSDk
 github.com/coreos/etcd v3.3.10+incompatible/go.mod h1:uF7uidLiAD3TWHmW31ZFd/JWoc32PjwdhPthX9715RE=
 github.com/coreos/go-etcd v2.0.0+incompatible/go.mod h1:Jez6KQU2B/sWsbdaef3ED8NzMklzPG4d5KIOhIy30Tk=
 github.com/coreos/go-semver v0.2.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
+github.com/coreos/go-systemd v0.0.0-20190321100706-95778dfbb74e/go.mod h1:F5haX7vjVVG0kc13fIWeqUViNPyEJxv/OmvnBo0Yme4=
 github.com/cpuguy83/go-md2man v1.0.10/go.mod h1:SmD6nW6nTyfqj6ABTjUi3V3JVMnlJmwcJI5acqYI6dE=
 github.com/davecgh/go-spew v0.0.0-20151105211317-5215b55f46b2/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
@@ -153,6 +154,7 @@ github.com/opencontainers/go-digest v1.0.0-rc1/go.mod h1:cMLVZDEM3+U2I4VmLI6N8jQ
 github.com/pelletier/go-toml v1.2.0/go.mod h1:5z9KED0ma1S8pY6P1sdut58dfprrGBbd/94hg7ilaic=
 github.com/peterbourgon/diskv v2.0.1+incompatible/go.mod h1:uqqh8zWWbv1HBMNONnaR/tNboyR3/BZd58JJSHlUSCU=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v0.0.0-20151028094244-d8ed2627bdf0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
@@ -164,6 +166,9 @@ github.com/prometheus/common v0.4.1/go.mod h1:TNfzLD0ON7rHzMJeJkieUDPYmFC7Snx/y8
 github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/prometheus/procfs v0.0.2/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
 github.com/remyoudompheng/bigfft v0.0.0-20170806203942-52369c62f446/go.mod h1:uYEyJGbgTkfkS4+E/PavXkNJcbFIpEtjt2B0KDQ5+9M=
+github.com/rs/xid v1.2.1/go.mod h1:+uKXf+4Djp6Md1KODXJxgGQPKngRmWyn10oCKFzNHOQ=
+github.com/rs/zerolog v1.18.0 h1:CbAm3kP2Tptby1i9sYy2MGRg0uxIN9cyDb59Ys7W8z8=
+github.com/rs/zerolog v1.18.0/go.mod h1:9nvC1axdVrAHcu/s9taAVfBuIdTZLVQmKQyvrUjF5+I=
 github.com/russross/blackfriday v1.5.2/go.mod h1:JO/DiYxRf+HjHt06OyowR9PTA263kcR/rfWxYHBV53g=
 github.com/sirupsen/logrus v1.2.0/go.mod h1:LxeOpSwHxABJmUn/MG1IvRgCAasNZTLOkJPxbbu5VWo=
 github.com/sirupsen/logrus v1.4.2 h1:SPIRibHv4MatM3XXNO2BJeFLZwZ2LvZgfQ5+UNI2im4=
@@ -187,6 +192,7 @@ github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/ugorji/go/codec v0.0.0-20181204163529-d75b2dcb6bc8/go.mod h1:VFNgLljTbGfSG7qAOspJ7OScBnGdDN/yBr0sguwnwf0=
 github.com/xordataexchange/crypt v0.0.3-0.20170626215501-b2862e3d0a77/go.mod h1:aYKd//L2LvnjZzWKhF00oedf4jCCReLcmhLdhm1A27Q=
+github.com/zenazn/goji v0.9.0/go.mod h1:7S9M489iMyHBNxwZnk9/EHS098H4/F6TATF2mIxtB1Q=
 go.opencensus.io v0.21.0/go.mod h1:mSImk1erAIZhrmZN+AvHh14ztQfjbGwt4TtuofqLduU=
 golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20181203042331-505ab145d0a9/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
@@ -214,6 +220,7 @@ golang.org/x/net v0.0.0-20190311183353-d8887717615a h1:oWX7TPOiFAMXLq8o0ikBYfCJV
 golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/net v0.0.0-20190613194153-d28f0bde5980/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/net v0.0.0-20190812203447-cdfb69ac37fc h1:gkKoSkUmnU6bpS/VhkuO27bzQeSA51uaEfbOW5dNb68=
 golang.org/x/net v0.0.0-20190812203447-cdfb69ac37fc/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
@@ -257,6 +264,8 @@ golang.org/x/tools v0.0.0-20190312151545-0bb0c0a6e846/go.mod h1:LCzVGOaR6xXOjkQ3
 golang.org/x/tools v0.0.0-20190312170243-e65039ee4138/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
 golang.org/x/tools v0.0.0-20190614205625-5aca471b1d59/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
 golang.org/x/tools v0.0.0-20190621195816-6e04913cbbac/go.mod h1:/rFqwRUd4F7ZHNgwSSTFct+R/Kf4OFW1sUzUTQQTgfc=
+golang.org/x/tools v0.0.0-20190828213141-aed303cbaa74/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 gonum.org/v1/gonum v0.0.0-20190331200053-3d26580ed485/go.mod h1:2ltnJ7xHfj0zHS40VVPYEAAMTa3ZGguvHGBSJeRWqE0=
 gonum.org/v1/netlib v0.0.0-20190313105609-8cb42192e0e0/go.mod h1:wa6Ws7BG/ESfp6dHfk7C6KdzKA7wR7u/rKwOGE66zvw=
 gonum.org/v1/netlib v0.0.0-20190331212654-76723241ea4e/go.mod h1:kS+toOQn6AQKjmKJ7gzohV1XkqsFehRA2FbsbkopSuQ=
@@ -309,7 +318,6 @@ k8s.io/kube-openapi v0.0.0-20190816220812-743ec37842bf h1:EYm5AW/UUDbnmnI+gK0TJD
 k8s.io/kube-openapi v0.0.0-20190816220812-743ec37842bf/go.mod h1:1TqjTSzOxsLGIKfj0lK8EeCP7K1iUG65v09OM0/WG5E=
 k8s.io/kubectl v0.0.0-20191016234702-5d0b8f240400 h1:IeGIAmvzKqd9LLSWCXXFKbenbJCu9faeIulMgYz77YY=
 k8s.io/kubectl v0.0.0-20191016234702-5d0b8f240400/go.mod h1:939lYu2PWLrk5t7xWN3amNIvJlJCa7KQfPZ2+cLrnJA=
-k8s.io/kubernetes v1.17.2 h1:g1UFZqFQsYx88xMUks4PKC6tsNcekxe0v06fcVGRwVE=
 k8s.io/metrics v0.0.0-20191014074242-8b0351268f72/go.mod h1:ie2c8bq97BFtf7noiNVVJmLhEjShRhE4KBVFxeZCSjs=
 k8s.io/utils v0.0.0-20191010214722-8d271d903fe4 h1:Gi+/O1saihwDqnlmC8Vhv1M5Sp4+rbOmK9TbsLn8ZEA=
 k8s.io/utils v0.0.0-20191010214722-8d271d903fe4/go.mod h1:sZAwmy6armz5eXlNoLmJcl4F1QuKu7sr+mFQ0byX7Ew=

pkg/config/config.go

@@ -16,9 +16,10 @@ package config
 import (
 	"flag"
 	"fmt"
-	"log"
 	"os"
 	"strconv"
+
+	"github.com/rs/zerolog/log"
 )
 
 const (
@@ -49,6 +50,8 @@ const (
 	metadataTriesConfigKey                  = "METADATA_TRIES"
 	metadataTriesDefault                    = 3
 	cordonOnly                              = "CORDON_ONLY"
+	jsonLoggingConfigKey                    = "JSON_LOGGING"
+	jsonLoggingDefault                      = false
 )
 
 //Config arguments set via CLI, environment variables, or defaults
@@ -69,6 +72,7 @@ type Config struct {
 	EnableSpotInterruptionDraining bool
 	MetadataTries                  int
 	CordonOnly                     bool
+	JsonLogging                    bool
 }
 
 //ParseCliArgs parses cli arguments and uses environment variables as fallback values
@@ -99,13 +103,14 @@ func ParseCliArgs() (config Config, err error) {
 	flag.BoolVar(&config.EnableSpotInterruptionDraining, "enable-spot-interruption-draining", getBoolEnv(enableSpotInterruptionDrainingConfigKey, enableSpotInterruptionDrainingDefault), "If true, drain nodes when the spot interruption termination notice is received")
 	flag.IntVar(&config.MetadataTries, "metadata-tries", getIntEnv(metadataTriesConfigKey, metadataTriesDefault), "The number of times to try requesting metadata. If you would like 2 retries, set metadata-tries to 3.")
 	flag.BoolVar(&config.CordonOnly, "cordon-only", getBoolEnv(cordonOnly, false), "If true, nodes will be cordoned but not drained when an interruption event occurs.")
+	flag.BoolVar(&config.JsonLogging, "json-logging", getBoolEnv(jsonLoggingConfigKey, jsonLoggingDefault), "If true, use JSON-formatted logs instead of human readable logs.")
 
 	flag.Parse()
 
 	if isConfigProvided("pod-termination-grace-period", podTerminationGracePeriodConfigKey) && isConfigProvided("grace-period", gracePeriodConfigKey) {
-		log.Println("Deprecated argument \"grace-period\" and the replacement argument \"pod-termination-grace-period\" was provided. Using the newer argument \"pod-termination-grace-period\"")
+		log.Print("Deprecated argument \"grace-period\" and the replacement argument \"pod-termination-grace-period\" was provided. Using the newer argument \"pod-termination-grace-period\"")
 	} else if isConfigProvided("grace-period", gracePeriodConfigKey) {
-		log.Println("Deprecated argument \"grace-period\" was provided. This argument will eventually be removed. Please switch to \"pod-termination-grace-period\" instead.")
+		log.Print("Deprecated argument \"grace-period\" was provided. This argument will eventually be removed. Please switch to \"pod-termination-grace-period\" instead.")
 		config.PodTerminationGracePeriod = gracePeriod
 	}
 
@@ -132,7 +137,8 @@ func ParseCliArgs() (config Config, err error) {
 			"\tenable-scheduled-event-draining: %t,\n"+
 			"\tenable-spot-interruption-draining: %t,\n"+
 			"\tmetadata-tries: %d,\n"+
-			"\tcordon-only: %t,\n",
+			"\tcordon-only: %t,\n"+
+			"\tjson-logging: %t,\n",
 
 		config.DryRun,
 		config.NodeName,
@@ -147,6 +153,7 @@ func ParseCliArgs() (config Config, err error) {
 		config.EnableSpotInterruptionDraining,
 		config.MetadataTries,
 		config.CordonOnly,
+		config.JsonLogging,
 	)
 
 	return config, err

pkg/ec2metadata/ec2metadata.go

@@ -17,12 +17,13 @@ import (
 	"encoding/json"
 	"fmt"
 	"io/ioutil"
-	"log"
 	"math/rand"
 	"net/http"
 	"strconv"
 	"sync"
 	"time"
+
+	"github.com/rs/zerolog/log"
 )
 
 const (
@@ -218,7 +219,7 @@ func (e *Service) getV2Token() (string, int, error) {
 	httpReq := func() (*http.Response, error) {
 		return e.httpClient.Do(req)
 	}
-	log.Println("Trying to get token from IMDSv2")
+	log.Print("Trying to get token from IMDSv2")
 	resp, err := retry(1, 2*time.Second, httpReq)
 	if err != nil {
 		return "", -1, err
@@ -235,7 +236,7 @@ func (e *Service) getV2Token() (string, int, error) {
 	if err != nil {
 		return "", -1, fmt.Errorf("IMDS v2 Token TTL header not sent in response: %w", err)
 	}
-	log.Println("Got token from IMDSv2")
+	log.Print("Got token from IMDSv2")
 	return string(token), ttl, nil
 }
 
@@ -258,8 +259,8 @@ func retry(attempts int, sleep time.Duration, httpReq func() (*http.Response, er
 			jitter := time.Duration(rand.Int63n(int64(sleep)))
 			sleep = sleep + jitter/2
 
-			log.Printf("Request failed. Attempts remaining: %d\n", attempts)
-			log.Printf("Sleep for %s seconds\n", sleep)
+			log.Printf("Request failed. Attempts remaining: %d", attempts)
+			log.Printf("Sleep for %s seconds", sleep)
 			time.Sleep(sleep)
 			return retry(attempts, 2*sleep, httpReq)
 		}