feat: set ryuk port using the environment variable (#64)

* feat: set Ryuk port from the environment

* chore: deprecate the usage of the port flag

If the env var is present, it will take precedence over the flag

* feat: support configuring reconnection timeout from the environment

* docs: document the new ways to configure Ryuk

* docs: update usage

* fix: use Docker Hub

README.md

@@ -6,9 +6,9 @@ This project helps you to remove containers/networks/volumes/images by given fil
 
 1. Start it:
 
-        $ ./bin/moby-ryuk -p 8080
+        $ RYUK_PORT=8080 ./bin/moby-ryuk
         $ # You can also run it with Docker
-        $ docker run -v /var/run/docker.sock:/var/run/docker.sock -p 8080:8080 quay.io/testcontainers/ryuk
+        $ docker run -v /var/run/docker.sock:/var/run/docker.sock -e RYUK_PORT=8080 -p 8080:8080 docker.io/testcontainers/ryuk
 
 1. Connect via TCP:
 
@@ -38,3 +38,5 @@ This project helps you to remove containers/networks/volumes/images by given fil
 ## Ryuk configuration
 
 - `RYUK_CONNECTION_TIMEOUT` - Environment variable that defines the timeout for Ryuk to receive the first connection (default: 60s). Value layout is described in [time.ParseDuration](https://golang.org/pkg/time/#ParseDuration) documentation.
+- `RYUK_PORT` - Environment variable that defines the port where Ryuk will be bound to (default: 8080).
+- `RYUK_RECONNECTION_TIMEOUT` - Environment variable that defines the timeout for Ryuk to reconnect to Docker (default: 10s). Value layout is described in [time.ParseDuration](https://golang.org/pkg/time/#ParseDuration) documentation.

main.go

@@ -10,6 +10,7 @@ import (
 	"net/url"
 	"os"
 	"os/signal"
+	"strconv"
 	"strings"
 	"sync"
 	"syscall"
@@ -22,8 +23,10 @@ import (
 )
 
 const (
-	connectionTimeoutEnv string = "RYUK_CONNECTION_TIMEOUT"
-	ryukLabel            string = "org.testcontainers.ryuk"
+	connectionTimeoutEnv   string = "RYUK_CONNECTION_TIMEOUT"
+	portEnv                string = "RYUK_PORT"
+	reconnectionTimeoutEnv string = "RYUK_RECONNECTION_TIMEOUT"
+	ryukLabel              string = "org.testcontainers.ryuk"
 )
 
 var (
@@ -43,14 +46,15 @@ type config struct {
 // while parsing RYUK_CONNECTION_TIMEOUT the error is returned.
 func newConfig(args []string) (*config, error) {
 	cfg := config{
+		Port:                8080,
 		ConnectionTimeout:   60 * time.Second,
 		ReconnectionTimeout: 10 * time.Second,
 	}
 
 	fs := flag.NewFlagSet("ryuk", flag.ExitOnError)
 	fs.SetOutput(os.Stdout)
 
-	fs.IntVar(&cfg.Port, "p", 8080, "Port to bind at")
+	fs.IntVar(&cfg.Port, "p", 8080, "Deprecated: please use the "+portEnv+" environment variable to set the port to bind at")
 
 	err := fs.Parse(args)
 	if err != nil {
@@ -66,6 +70,24 @@ func newConfig(args []string) (*config, error) {
 		cfg.ConnectionTimeout = parsedTimeout
 	}
 
+	if port, ok := os.LookupEnv(portEnv); ok {
+		parsedPort, err := strconv.Atoi(port)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse \"%s\": %s", portEnv, err)
+		}
+
+		cfg.Port = parsedPort
+	}
+
+	if timeout, ok := os.LookupEnv(reconnectionTimeoutEnv); ok {
+		parsedTimeout, err := time.ParseDuration(timeout)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse \"%s\": %s", reconnectionTimeoutEnv, err)
+		}
+
+		cfg.ReconnectionTimeout = parsedTimeout
+	}
+
 	return &cfg, nil
 }
 

main_test.go

@@ -313,25 +313,65 @@ func TestPrune(t *testing.T) {
 }
 
 func Test_newConfig(t *testing.T) {
-	t.Run("should return an error when failing to parse the environment variable", func(t *testing.T) {
+	t.Run("should return an error when failing to parse RYUK_CONNECTION_TIMEOUT environment variable", func(t *testing.T) {
 		t.Setenv(connectionTimeoutEnv, "bad_value")
 
 		config, err := newConfig([]string{})
 		require.NotNil(t, err)
 		require.Nil(t, config)
 	})
 
-	t.Run("should set connectionTimeout with the environment variable", func(t *testing.T) {
+	t.Run("should set connectionTimeout with RYUK_CONNECTION_TIMEOUT environment variable", func(t *testing.T) {
 		t.Setenv(connectionTimeoutEnv, "10s")
 
 		config, err := newConfig([]string{})
 		require.Nil(t, err)
 		assert.Equal(t, 10*time.Second, config.ConnectionTimeout)
 	})
 
-	t.Run("should set port", func(t *testing.T) {
+	t.Run("should return an error when failing to parse RYUK_PORT environment variable", func(t *testing.T) {
+		t.Setenv(portEnv, "bad_value")
+
+		config, err := newConfig([]string{})
+		require.NotNil(t, err)
+		require.Nil(t, config)
+	})
+
+	t.Run("should set connectionTimeout with RYUK_PORT environment variable", func(t *testing.T) {
+		t.Setenv(portEnv, "8081")
+
+		config, err := newConfig([]string{})
+		require.Nil(t, err)
+		assert.Equal(t, 8081, config.Port)
+	})
+
+	t.Run("should return an error when failing to parse RYUK_RECONNECTION_TIMEOUT environment variable", func(t *testing.T) {
+		t.Setenv(reconnectionTimeoutEnv, "bad_value")
+
+		config, err := newConfig([]string{})
+		require.NotNil(t, err)
+		require.Nil(t, config)
+	})
+
+	t.Run("should set connectionTimeout with RYUK_RECONNECTION_TIMEOUT environment variable", func(t *testing.T) {
+		t.Setenv(reconnectionTimeoutEnv, "100s")
+
+		config, err := newConfig([]string{})
+		require.Nil(t, err)
+		assert.Equal(t, 100*time.Second, config.ReconnectionTimeout)
+	})
+
+	t.Run("should set port with port flag", func(t *testing.T) {
 		config, err := newConfig([]string{"-p", "3000"})
 		require.Nil(t, err)
 		assert.Equal(t, 3000, config.Port)
 	})
+
+	t.Run("should set port from env with port flag and RYUK_PORT environment variable", func(t *testing.T) {
+		t.Setenv(portEnv, "8081")
+
+		config, err := newConfig([]string{"-p", "3000"})
+		require.Nil(t, err)
+		assert.Equal(t, 8081, config.Port)
+	})
 }