fix: fix ngrok memory leak (#1228)

* fix: fix ngrok memory leak

Signed-off-by: João Vanzuita <joao@kubeshop.io>

cmd/local/local.go

@@ -1,6 +1,7 @@
 package local
 
 import (
+	"context"
 	"fmt"
 	"sync"
 	"time"
@@ -40,6 +41,10 @@ var (
 	adminEmail     string
 	templateTag    string
 	logLevel       string
+
+	// ngrok context that is used to control ngrok context cancellation, and is called at the end of the installation,
+	// after the user closes Kubefirst installer.
+	cancelContext context.CancelFunc
 )
 
 func NewCommand() *cobra.Command {

cmd/local/postrun.go

@@ -1,10 +1,7 @@
 package local
 
 import (
-	"os"
-	"os/signal"
-	"sync"
-	"syscall"
+	"time"
 
 	"github.com/rs/zerolog/log"
 
@@ -36,14 +33,21 @@ func runPostLocal(cmd *cobra.Command, args []string) error {
 	log.Info().Msgf("Kubefirst Console available at: %s", pkg.KubefirstConsoleLocalURLTLS)
 
 	// managing termination signal from the terminal
-	sigs := make(chan os.Signal, 1)
-	signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
-	var wg sync.WaitGroup
-	wg.Add(1)
-	go func() {
-		<-sigs
-		wg.Done()
-	}()
+	// todo: handle user inputs (q, ctrl+c, etc)
+	//sigs := make(chan os.Signal, 1)
+	//signal.Notify(sigs, syscall.SIGINT, syscall.SIGTERM)
+	//var wg sync.WaitGroup
+	//wg.Add(1)
+	//go func() {
+	//	<-sigs
+	//	wg.Done()
+	//}()
+	//wg.Wait()
+
+	cancelContext()
+	log.Info().Msg("ngrok context killed")
+	// force wait context kill
+	time.Sleep(1 * time.Second)
 
 	return nil
 }

cmd/local/prerun.go

@@ -102,7 +102,11 @@ func validateLocal(cmd *cobra.Command, args []string) error {
 		return err
 	}
 
-	go pkg.RunNgrok(context.TODO())
+	// creates a new context, and a cancel function that allows canceling the context. The context is passed as an
+	// argument to the RunNgrok function, which is then started in a new goroutine.
+	var ctx context.Context
+	ctx, cancelContext = context.WithCancel(context.Background())
+	go pkg.RunNgrok(ctx)
 
 	viper.Set("github.atlantis.webhook.secret", pkg.Random(20))
 	viper.Set("github.user", githubUser)

go.mod

@@ -33,6 +33,7 @@ require (
 	github.com/segmentio/analytics-go v3.1.0+incompatible
 	github.com/spf13/cobra v1.4.0
 	github.com/spf13/viper v1.11.0
+	golang.ngrok.com/ngrok v1.0.0
 	golang.org/x/crypto v0.0.0-20220722155217-630584e8d5aa
 	golang.org/x/exp v0.0.0-20220827204233-334a2380cb91
 	golang.org/x/sync v0.0.0-20201207232520-09787c993a3a
@@ -55,7 +56,8 @@ require (
 	github.com/gobwas/pool v0.2.1 // indirect
 	github.com/gobwas/ws v1.1.0 // indirect
 	github.com/hashicorp/vault/sdk v0.6.0 // indirect
-	github.com/inconshreveable/log15 v0.0.0-20201112154412-8562bdadbbac // indirect
+	github.com/inconshreveable/log15 v3.0.0-testing.3+incompatible // indirect
+	github.com/inconshreveable/log15/v3 v3.0.0-testing.5 // indirect
 	github.com/josharian/intern v1.0.0 // indirect
 	github.com/jpillora/backoff v1.0.0 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
@@ -127,8 +129,8 @@ require (
 	github.com/kevinburke/ssh_config v0.0.0-20201106050909-4977a11b4351 // indirect
 	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
 	github.com/magiconair/properties v1.8.6 // indirect
-	github.com/mattn/go-colorable v0.1.12 // indirect
-	github.com/mattn/go-isatty v0.0.14 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.16 // indirect
 	github.com/mattn/go-runewidth v0.0.13 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
 	github.com/mitchellh/go-homedir v1.1.0 // indirect
@@ -155,11 +157,11 @@ require (
 	github.com/subosito/gotenv v1.2.0 // indirect
 	github.com/xanzy/ssh-agent v0.3.0 // indirect
 	go.uber.org/atomic v1.9.0 // indirect
-	golang.org/x/net v0.0.0-20220812174116-3211cb980234 // indirect
+	golang.org/x/net v0.2.0 // indirect
 	golang.org/x/oauth2 v0.0.0-20220411215720-9780585627b5
-	golang.org/x/sys v0.0.0-20220928140112-f11e5e49a4ec // indirect
-	golang.org/x/term v0.0.0-20210927222741-03fcf44c2211 // indirect
-	golang.org/x/text v0.3.7 // indirect
+	golang.org/x/sys v0.2.0 // indirect
+	golang.org/x/term v0.2.0 // indirect
+	golang.org/x/text v0.4.0 // indirect
 	golang.org/x/time v0.0.0-20220411224347-583f2d630306 // indirect
 	google.golang.org/appengine v1.6.7 // indirect
 	google.golang.org/genproto v0.0.0-20220407144326-9054f6ed7bac // indirect

go.sum

@@ -388,8 +388,10 @@ github.com/ianlancetaylor/demangle v0.0.0-20200824232613-28f6c0f3b639/go.mod h1:
 github.com/imdario/mergo v0.3.5/go.mod h1:2EnlNZ0deacrJVfApfmtdGgDfMuh/nq6Ok1EcJh5FfA=
 github.com/imdario/mergo v0.3.12 h1:b6R2BslTbIEToALKP7LxUvijTsNI9TAe80pLWN2g/HU=
 github.com/imdario/mergo v0.3.12/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
-github.com/inconshreveable/log15 v0.0.0-20201112154412-8562bdadbbac h1:n1DqxAo4oWPMvH1+v+DLYlMCecgumhhgnxAPdqDIFHI=
-github.com/inconshreveable/log15 v0.0.0-20201112154412-8562bdadbbac/go.mod h1:cOaXtrgN4ScfRrD9Bre7U1thNq5RtJ8ZoP4iXVGRj6o=
+github.com/inconshreveable/log15 v3.0.0-testing.3+incompatible h1:zaX5fYT98jX5j4UhO/WbfY8T1HkgVrydiDMC9PWqGCo=
+github.com/inconshreveable/log15 v3.0.0-testing.3+incompatible/go.mod h1:cOaXtrgN4ScfRrD9Bre7U1thNq5RtJ8ZoP4iXVGRj6o=
+github.com/inconshreveable/log15/v3 v3.0.0-testing.5 h1:h4e0f3kjgg+RJBlKOabrohjHe47D3bbAB9BgMrc3DYA=
+github.com/inconshreveable/log15/v3 v3.0.0-testing.5/go.mod h1:3GQg1SVrLoWGfRv/kAZMsdyU5cp8eFc1P3cw+Wwku94=
 github.com/inconshreveable/mousetrap v1.0.0 h1:Z8tu5sraLXCXIcARxBp/8cbvlwVa7Z1NHg9XEKhtSvM=
 github.com/inconshreveable/mousetrap v1.0.0/go.mod h1:PxqpIevigyE2G7u3NXJIT2ANytuPF1OarO4DADm73n8=
 github.com/itchyny/gojq v0.12.8 h1:Zxcwq8w4IeR8JJYEtoG2MWJZUv0RGY6QqJcO1cqV8+A=
@@ -449,14 +451,16 @@ github.com/matryer/is v1.2.0/go.mod h1:2fLPjFQM9rhQ15aVEtbuwhJinnOqrmgXPNdZsdwlW
 github.com/mattn/go-colorable v0.0.9/go.mod h1:9vuHe8Xs5qXnSaW/c/ABM9alt+Vo+STaOChaDxuIBZU=
 github.com/mattn/go-colorable v0.1.4/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
 github.com/mattn/go-colorable v0.1.9/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
-github.com/mattn/go-colorable v0.1.12 h1:jF+Du6AlPIjs2BiUiQlKOX0rt3SujHxPnksPKZbaA40=
 github.com/mattn/go-colorable v0.1.12/go.mod h1:u5H1YNBxpqRaxsYJYSkiCWKzEfiAb1Gb520KVy5xxl4=
+github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
+github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
 github.com/mattn/go-isatty v0.0.3/go.mod h1:M+lRXTBqGeGNdLjl/ufCoiOlB5xdOkqRJdNxMWT7Zi4=
 github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
 github.com/mattn/go-isatty v0.0.10/go.mod h1:qgIWMr58cqv1PHHyhnkY9lrL7etaEgOFcMEpPG5Rm84=
 github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
-github.com/mattn/go-isatty v0.0.14 h1:yVuAays6BHfxijgZPzw+3Zlu5yQgKGP2/hcQbHb7S9Y=
 github.com/mattn/go-isatty v0.0.14/go.mod h1:7GGIvUiUoEMVVmxf/4nioHXj79iQHKdU27kJ6hsGG94=
+github.com/mattn/go-isatty v0.0.16 h1:bq3VjFmv/sOjHtdEhmkEV4x1AJtvUvOJ2PFAZ5+peKQ=
+github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
 github.com/mattn/go-runewidth v0.0.10/go.mod h1:RAqKPSqVFrSLVXbA8x7dzmKdmGzieGRCM46jaSJTDAk=
 github.com/mattn/go-runewidth v0.0.12/go.mod h1:RAqKPSqVFrSLVXbA8x7dzmKdmGzieGRCM46jaSJTDAk=
 github.com/mattn/go-runewidth v0.0.13 h1:lTGmDsbAYt5DmK6OnoV7EuIF1wEIFAcxld6ypU4OSgU=
@@ -620,6 +624,8 @@ go.opencensus.io v0.22.5/go.mod h1:5pWMHQbX5EPX2/62yrJeAkowc+lfs/XD7Uxpq3pI6kk=
 go.opentelemetry.io/proto/otlp v0.7.0/go.mod h1:PqfVotwruBrMGOCsRd/89rSnXhoiJIqeYNgFYFoEGnI=
 go.uber.org/atomic v1.9.0 h1:ECmE8Bn/WFTYwEW/bpKD3M8VtR/zQVbavAoalC1PYyE=
 go.uber.org/atomic v1.9.0/go.mod h1:fEN4uk6kAWBTFdckzkM89CLk9XfWZrxpCo0nPH17wJc=
+golang.ngrok.com/ngrok v1.0.0 h1:36xgYK8C05D4V/KslXc+Nm6E+qorNLv8zZiQCHO+FB4=
+golang.ngrok.com/ngrok v1.0.0/go.mod h1:h0SmDbrHimeTrjlMgUWh21Ni3e4s5SQZm2nMJZe3XHI=
 golang.org/x/crypto v0.0.0-20180904163835-0709b304e793/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20190219172222-a4c6cb3142f2/go.mod h1:6SG95UA2DQfeDnfUPMdvaQW0Q7yPrPDi9nlGo2tz2b4=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
@@ -710,8 +716,8 @@ golang.org/x/net v0.0.0-20210326060303-6b1517762897/go.mod h1:uSPa2vr4CLtc/ILN5o
 golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4/go.mod h1:p54w0d4576C0XHj96bSt6lcn1PtDYWL6XObtHCRCNQM=
 golang.org/x/net v0.0.0-20210520170846-37e1c6afe023/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.0.0-20220127200216-cd36cc0744dd/go.mod h1:CfG3xpIq0wQ8r1q4Su4UZFWDARRcnwPjda9FqA0JpMk=
-golang.org/x/net v0.0.0-20220812174116-3211cb980234 h1:RDqmgfe7SvlMWoqC3xwQ2blLO3fcWcxMa3eBLRdRW7E=
-golang.org/x/net v0.0.0-20220812174116-3211cb980234/go.mod h1:YDH+HFinaLZZlnHAfSS6ZXJJ9M9t4Dl22yv3iI2vPwk=
+golang.org/x/net v0.2.0 h1:sZfSu1wtKLGlWI4ZZayP0ck9Y73K1ynO6gqzTdBVdPU=
+golang.org/x/net v0.2.0/go.mod h1:KqCZLdyyvdV855qA2rE3GC2aiw5xGR5TEjj8smXukLY=
 golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U=
 golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
 golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw=
@@ -798,13 +804,15 @@ golang.org/x/sys v0.0.0-20211216021012-1d35b9e2eb4e/go.mod h1:oPkhp1MJrh7nUepCBc
 golang.org/x/sys v0.0.0-20220204135822-1c1b9b1eba6a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220209214540-3681064d5158/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20220928140112-f11e5e49a4ec h1:BkDtF2Ih9xZ7le9ndzTA7KJow28VbQW3odyk/8drmuI=
-golang.org/x/sys v0.0.0-20220928140112-f11e5e49a4ec/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.2.0 h1:ljd4t30dBnAvMZaQCevtY0xLLD0A+bRZXbgLMLU1F/A=
+golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
 golang.org/x/term v0.0.0-20201117132131-f5c789dd3221/go.mod h1:Nr5EML6q2oocZ2LXRh80K7BxOlk5/8JxuGnuhpl+muw=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/term v0.0.0-20210220032956-6a3ed077a48d/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
-golang.org/x/term v0.0.0-20210927222741-03fcf44c2211 h1:JGgROgKl9N8DuW20oFS5gxc+lE67/N3FcwmBPMe7ArY=
 golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
+golang.org/x/term v0.2.0 h1:z85xZCsEl7bi/KwbNADeBYoOP0++7W1ipu+aGnpwzRM=
+golang.org/x/term v0.2.0/go.mod h1:TVmDHMZPmdnySmBfhjOoOdhjzdE1h4u1VwSiw2l1Nuc=
 golang.org/x/text v0.0.0-20170915032832-14c0d48ead0c/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.1-0.20180807135948-17ff2d5776d2/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
@@ -813,8 +821,9 @@ golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.4/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.5/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.3.7 h1:olpwvP2KacW1ZWvsR7uQhoyTYvKAupfQrRGBFM352Gk=
 golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
+golang.org/x/text v0.4.0 h1:BrVqGRd7+k1DiOgtnFvAkoQEWQvBc25ouMJM6429SFg=
+golang.org/x/text v0.4.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
 golang.org/x/time v0.0.0-20181108054448-85acf8d2951c/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20190308202827-9d24e82272b4/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
 golang.org/x/time v0.0.0-20191024005414-555d28b269f0/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=

pkg/ngrok.go

@@ -2,56 +2,76 @@ package pkg
 
 import (
 	"context"
-	"fmt"
+	"github.com/spf13/viper"
+	"golang.ngrok.com/ngrok"
+	"golang.ngrok.com/ngrok/config"
 	"io"
 	"net"
-	"time"
 
 	"github.com/rs/zerolog/log"
-
-	"github.com/ngrok/ngrok-go"
-	"github.com/ngrok/ngrok-go/config"
-	"github.com/spf13/viper"
+	_ "github.com/spf13/viper"
 	"golang.org/x/sync/errgroup"
 )
 
+// RunNgrok creates a ngrok tunnel, listens for incoming connections, and starts a goroutine to handle each connection
+// with context passed to it, also it logs the errors and sets the url in viper. RunNgrok is called to run in goroutine
+// the caller needs to cancel the context to stop the tunnel.
 func RunNgrok(ctx context.Context) {
-
-	tunnel, err := ngrok.StartTunnel(ctx, config.HTTPEndpoint(), ngrok.WithAuthtokenFromEnv())
+	defer func() {
+		log.Info().Msg("RunNgrok context was cancelled, conn closed and not accepting new connections, and function exited")
+	}()
+	tunnel, err := ngrok.Listen(ctx, config.HTTPEndpoint(), ngrok.WithAuthtokenFromEnv())
 	if err != nil {
 		log.Error().Err(err).Msg("")
 	}
 
-	retry(3, time.Second, "create ngrok tunnel", func() error {
-		tunnel, err = ngrok.StartTunnel(ctx, config.HTTPEndpoint(), ngrok.WithAuthtokenFromEnv())
-		if err != nil {
-			log.Debug().Err(err).Msg("")
-			return err
+	// inform when tunnel is not accepting new connections
+	go func() {
+		select {
+		case <-ctx.Done():
+			log.Info().Msg("Ngrok is closed, and not accepting new connections")
 		}
-		return nil
-	})
+	}()
 
-	fmt.Println("tunnel created: ", tunnel.URL())
+	log.Info().Msgf("tunnel created: %s", tunnel.URL())
 	viper.Set("github.atlantis.webhook.url", tunnel.URL()+"/events")
 	viper.Set("ngrok.url", tunnel.URL())
-	viper.WriteConfig()
+	err = viper.WriteConfig()
+	if err != nil {
+		log.Error().Err(err).Msg("")
+		return
+	}
 
 	for {
+		log.Debug().Msgf("current state of the ngrok context is (if nil, its healthy): %s", ctx.Err())
+
 		conn, err := tunnel.Accept()
 		if err != nil {
 			log.Error().Err(err).Msg("")
+			break
 		}
 
-		log.Info().Msgf("accepted connection from %s", conn.RemoteAddr())
-
-		go func() {
-
-			err := handleConn(ctx, conn)
-			log.Info().Msgf("connection closed: %v", err)
-		}()
+		if ctx.Err() == nil {
+			log.Info().Msgf("Ngrok is accepting connections: %s", conn.RemoteAddr())
+			go func() {
+				err = handleConn(ctx, conn)
+				if err == nil {
+					return
+				}
+				log.Info().Err(err).Msg("connection closed: ")
+			}()
+		} else {
+			err := conn.Close()
+			if err != nil {
+				println(err)
+			}
+			break
+		}
 	}
 }
 
+// handleConn handles the connection by copying the data from the connection to the destination address and vice versa
+// it also logs the errors and closes the connection when the context is cancelled
 func handleConn(ctx context.Context, conn net.Conn) error {
 	next, err := net.Dial("tcp", ":80")
 	if err != nil {