Add log adapters for testing and log15

Make LogLevel a type for Stringer interface.

bench_test.go

@@ -179,7 +179,7 @@ func BenchmarkSelectWithoutLogging(b *testing.B) {
 
 type discardLogger struct{}
 
-func (dl discardLogger) Log(level int, msg string, ctx ...interface{}) {}
+func (dl discardLogger) Log(level pgx.LogLevel, msg string, ctx ...interface{}) {}
 
 func BenchmarkSelectWithLoggingTraceDiscard(b *testing.B) {
 	conn := mustConnect(b, *defaultConnConfig)

conn.go

@@ -1213,7 +1213,7 @@ func (c *Conn) shouldLog(lvl int) bool {
 	return c.logger != nil && c.logLevel >= lvl
 }
 
-func (c *Conn) log(lvl int, msg string, ctx ...interface{}) {
+func (c *Conn) log(lvl LogLevel, msg string, ctx ...interface{}) {
 	if c.pid != 0 {
 		ctx = append(ctx, "pid", c.PID)
 	}

conn_test.go

@@ -1739,7 +1739,7 @@ func TestCatchSimultaneousConnectionQueryAndExec(t *testing.T) {
 }
 
 type testLog struct {
-	lvl int
+	lvl pgx.LogLevel
 	msg string
 	ctx []interface{}
 }
@@ -1748,7 +1748,7 @@ type testLogger struct {
 	logs []testLog
 }
 
-func (l *testLogger) Log(level int, msg string, ctx ...interface{}) {
+func (l *testLogger) Log(level pgx.LogLevel, msg string, ctx ...interface{}) {
 	l.logs = append(l.logs, testLog{lvl: level, msg: msg, ctx: ctx})
 }
 

examples/url_shortener/main.go

@@ -1,11 +1,13 @@
 package main
 
 import (
-	"github.com/jackc/pgx"
-	log "gopkg.in/inconshreveable/log15.v2"
 	"io/ioutil"
 	"net/http"
 	"os"
+
+	"github.com/jackc/pgx"
+	"github.com/jackc/pgx/log/log15adapter"
+	log "gopkg.in/inconshreveable/log15.v2"
 )
 
 var pool *pgx.ConnPool
@@ -98,27 +100,8 @@ func urlHandler(w http.ResponseWriter, req *http.Request) {
 	}
 }
 
-type log15Adapter struct {
-	logger log.Logger
-}
-
-func (a *log15Adapter) Log(level int, msg string, ctx ...interface{}) {
-	switch level {
-	case pgx.LogLevelTrace, pgx.LogLevelDebug:
-		a.logger.Debug(msg, ctx...)
-	case pgx.LogLevelInfo:
-		a.logger.Info(msg, ctx...)
-	case pgx.LogLevelWarn:
-		a.logger.Warn(msg, ctx...)
-	case pgx.LogLevelError:
-		a.logger.Error(msg, ctx...)
-	default:
-		panic("invalid log level")
-	}
-}
-
 func main() {
-	logger := &log15Adapter{logger: log.New("module", "pgx")}
+	logger := log15adapter.NewLogger(log.New("module", "pgx"))
 
 	var err error
 	connPoolConfig := pgx.ConnPoolConfig{

log/log15adapter/adapter.go

@@ -0,0 +1,42 @@
+// Package log15adapter provides a logger that writes to a github.com/inconshreveable/log15.Logger
+// log.
+package log15adapter
+
+import (
+	"github.com/jackc/pgx"
+)
+
+// Log15Logger interface defines the subset of
+// github.com/inconshreveable/log15.Logger that this adapter uses.
+type Log15Logger interface {
+	Debug(msg string, ctx ...interface{})
+	Info(msg string, ctx ...interface{})
+	Warn(msg string, ctx ...interface{})
+	Error(msg string, ctx ...interface{})
+	Crit(msg string, ctx ...interface{})
+}
+
+type Logger struct {
+	l Log15Logger
+}
+
+func NewLogger(l Log15Logger) *Logger {
+	return &Logger{l: l}
+}
+
+func (l *Logger) Log(level pgx.LogLevel, msg string, ctx ...interface{}) {
+	switch level {
+	case pgx.LogLevelTrace:
+		l.l.Debug(msg, append(ctx, "PGX_LOG_LEVEL", level)...)
+	case pgx.LogLevelDebug:
+		l.l.Debug(msg, ctx...)
+	case pgx.LogLevelInfo:
+		l.l.Info(msg, ctx...)
+	case pgx.LogLevelWarn:
+		l.l.Warn(msg, ctx...)
+	case pgx.LogLevelError:
+		l.l.Error(msg, ctx...)
+	default:
+		l.l.Error(msg, append(ctx, "INVALID_PGX_LOG_LEVEL", level)...)
+	}
+}

log/testingadapter/adapter.go

@@ -0,0 +1,25 @@
+// Package testingadapter provides a logger that writes to a test or benchmark
+// log.
+package testingadapter
+
+import (
+	"github.com/jackc/pgx"
+)
+
+// TestingLogger interface defines the subset of testing.TB methods used by this
+// adapter.
+type TestingLogger interface {
+	Log(args ...interface{})
+}
+
+type Logger struct {
+	l TestingLogger
+}
+
+func NewLogger(l TestingLogger) *Logger {
+	return &Logger{l: l}
+}
+
+func (l *Logger) Log(level pgx.LogLevel, msg string, ctx ...interface{}) {
+	l.l.Log(level, msg, ctx)
+}

logger.go

@@ -17,10 +17,33 @@ const (
 	LogLevelNone  = 1
 )
 
+// LogLevel represents the pgx logging level. See LogLevel* constants for
+// possible values.
+type LogLevel int
+
+func (ll LogLevel) String() string {
+	switch ll {
+	case LogLevelTrace:
+		return "trace"
+	case LogLevelDebug:
+		return "debug"
+	case LogLevelInfo:
+		return "info"
+	case LogLevelWarn:
+		return "warn"
+	case LogLevelError:
+		return "error"
+	case LogLevelNone:
+		return "none"
+	default:
+		return fmt.Sprintf("invalid level %d", ll)
+	}
+}
+
 // Logger is the interface used to get logging from pgx internals.
 type Logger interface {
 	// Log a message at the given level with context key/value pairs
-	Log(level int, msg string, ctx ...interface{})
+	Log(level LogLevel, msg string, ctx ...interface{})
 }
 
 // LogLevelFromString converts log level string to constant
@@ -32,7 +55,7 @@ type Logger interface {
 //	warn
 //	error
 //	none
-func LogLevelFromString(s string) (int, error) {
+func LogLevelFromString(s string) (LogLevel, error) {
 	switch s {
 	case "trace":
 		return LogLevelTrace, nil

stdlib/sql_test.go

@@ -365,7 +365,7 @@ func TestConnQuery(t *testing.T) {
 }
 
 type testLog struct {
-	lvl int
+	lvl pgx.LogLevel
 	msg string
 	ctx []interface{}
 }
@@ -374,7 +374,7 @@ type testLogger struct {
 	logs []testLog
 }
 
-func (l *testLogger) Log(lvl int, msg string, ctx ...interface{}) {
+func (l *testLogger) Log(lvl pgx.LogLevel, msg string, ctx ...interface{}) {
 	l.logs = append(l.logs, testLog{lvl: lvl, msg: msg, ctx: ctx})
 }