make the log level env variable a string

Changelog.md

@@ -6,4 +6,5 @@
 - Add a `quic.Config` option to request truncation of the connection ID from a server
 - Add a `quic.Config` option to configure the source address validation
 - Add a `quic.Config` option to configure the handshake timeout
+- Changed the log level environment variable to only accept strings ("DEBUG", "INFO", "ERROR"), see [the wiki](https://github.com/lucas-clemente/quic-go/wiki/Logging) for more details.
 - Various bugfixes

internal/utils/log.go

@@ -1,26 +1,26 @@
 package utils
 
 import (
+	"fmt"
 	"log"
 	"os"
-	"strconv"
 	"time"
 )
 
 // LogLevel of quic-go
 type LogLevel uint8
 
-const (
-	logEnv = "QUIC_GO_LOG_LEVEL"
+const logEnv = "QUIC_GO_LOG_LEVEL"
 
+const (
 	// LogLevelNothing disables
-	LogLevelNothing LogLevel = 0
+	LogLevelNothing LogLevel = iota
 	// LogLevelError enables err logs
-	LogLevelError LogLevel = 1
+	LogLevelError
 	// LogLevelInfo enables info logs (e.g. packets)
-	LogLevelInfo LogLevel = 2
+	LogLevelInfo
 	// LogLevelDebug enables debug logs (e.g. packet contents)
-	LogLevelDebug LogLevel = 3
+	LogLevelDebug
 )
 
 var (
@@ -79,13 +79,16 @@ func init() {
 }
 
 func readLoggingEnv() {
-	env := os.Getenv(logEnv)
-	if env == "" {
+	switch os.Getenv(logEnv) {
+	case "":
 		return
+	case "DEBUG":
+		logLevel = LogLevelDebug
+	case "INFO":
+		logLevel = LogLevelInfo
+	case "ERROR":
+		logLevel = LogLevelError
+	default:
+		fmt.Fprintln(os.Stderr, "invalid quic-go log level, see https://github.com/lucas-clemente/quic-go/wiki/Logging")
 	}
-	level, err := strconv.Atoi(env)
-	if err != nil {
-		return
-	}
-	logLevel = LogLevel(level)
 }

internal/utils/log_test.go

@@ -97,20 +97,37 @@ var _ = Describe("Log", func() {
 		Expect(Debug()).To(BeTrue())
 	})
 
-	It("reads log level from env", func() {
-		Expect(logLevel).To(Equal(LogLevelNothing))
-		os.Setenv(logEnv, "3")
-		readLoggingEnv()
-		Expect(logLevel).To(Equal(LogLevelDebug))
-	})
+	Context("reading from env", func() {
+		BeforeEach(func() {
+			Expect(logLevel).To(Equal(LogLevelNothing))
+		})
 
-	It("does not error reading invalid log levels from env", func() {
-		Expect(logLevel).To(Equal(LogLevelNothing))
-		os.Setenv(logEnv, "")
-		readLoggingEnv()
-		Expect(logLevel).To(Equal(LogLevelNothing))
-		os.Setenv(logEnv, "asdf")
-		readLoggingEnv()
-		Expect(logLevel).To(Equal(LogLevelNothing))
+		It("reads DEBUG", func() {
+			os.Setenv(logEnv, "DEBUG")
+			readLoggingEnv()
+			Expect(logLevel).To(Equal(LogLevelDebug))
+		})
+
+		It("reads INFO", func() {
+			os.Setenv(logEnv, "INFO")
+			readLoggingEnv()
+			Expect(logLevel).To(Equal(LogLevelInfo))
+		})
+
+		It("reads ERROR", func() {
+			os.Setenv(logEnv, "ERROR")
+			readLoggingEnv()
+			Expect(logLevel).To(Equal(LogLevelError))
+		})
+
+		It("does not error reading invalid log levels from env", func() {
+			Expect(logLevel).To(Equal(LogLevelNothing))
+			os.Setenv(logEnv, "")
+			readLoggingEnv()
+			Expect(logLevel).To(Equal(LogLevelNothing))
+			os.Setenv(logEnv, "asdf")
+			readLoggingEnv()
+			Expect(logLevel).To(Equal(LogLevelNothing))
+		})
 	})
 })