snapshot of https://github.com/mattermost/mattermost.git (master, 2026-09-16; blobs > 131072B omitted)

server/public/shared/mlog/tlog.go

@@ -0,0 +1,145 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+package mlog
+
+import (
+	"bytes"
+	"io"
+	"os"
+	"sync"
+	"testing"
+
+	"github.com/mattermost/logr/v2"
+	"github.com/mattermost/logr/v2/formatters"
+	"github.com/mattermost/logr/v2/targets"
+)
+
+// AddWriterTarget adds a simple io.Writer target to an existing Logger.
+// The `io.Writer` can be a buffer which is useful for testing.
+// When adding a buffer to collect logs make sure to use `mlog.Buffer` which is
+// a thread safe version of `bytes.Buffer`.
+func AddWriterTarget(logger *Logger, w io.Writer, useJSON bool, levels ...Level) error {
+	filter := logr.NewCustomFilter(levels...)
+
+	var formatter logr.Formatter
+	if useJSON {
+		formatter = &formatters.JSON{EnableCaller: true}
+	} else {
+		formatter = &formatters.Plain{EnableCaller: true}
+	}
+
+	target := targets.NewWriterTarget(w)
+	return logger.log.Logr().AddTarget(target, "_testWriter", filter, formatter, 1000)
+}
+
+// CreateConsole createa a logger that outputs to [os.Stdout].
+// It's useful in places where no log configuration is accessible.
+func CreateConsoleLogger() *Logger {
+	logger, err := NewLogger()
+	if err != nil {
+		panic("failed create logger " + err.Error())
+	}
+
+	filter := logr.StdFilter{
+		Lvl:        LvlTrace,
+		Stacktrace: LvlPanic,
+	}
+	formatter := &formatters.Plain{
+		EnableCaller: true,
+		EnableColor:  true,
+	}
+
+	target := targets.NewWriterTarget(os.Stdout)
+	if err := logger.log.Logr().AddTarget(target, "_testcon", filter, formatter, 1000); err != nil {
+		panic("failed to add target " + err.Error())
+	}
+
+	return logger
+}
+
+// CreateConsoleTestLogger creates a logger for unit tests. Log records are output to `os.Stdout`.
+// All log messages with level trace or lower are logged.
+// The returned logger get Shutdown() when the tests completes. The caller should not shut it down.
+func CreateConsoleTestLogger(tb testing.TB) *Logger {
+	tb.Helper()
+
+	logger, err := NewLogger()
+	if err != nil {
+		tb.Fatalf("failed create logger %v", err)
+	}
+
+	filter := logr.StdFilter{
+		Lvl:        LvlTrace,
+		Stacktrace: LvlPanic,
+	}
+	formatter := &formatters.Plain{EnableCaller: true}
+
+	target := targets.NewWriterTarget(os.Stdout)
+	if err := logger.log.Logr().AddTarget(target, "_testcon", filter, formatter, 1000); err != nil {
+		tb.Fatalf("failed to add target %v", err)
+	}
+
+	tb.Cleanup(func() {
+		err := logger.Shutdown()
+		if err != nil {
+			tb.Fatalf("failed to shut down test logger %v", err)
+		}
+	})
+
+	return logger
+}
+
+// CreateTestLogger creates a logger for unit tests. Log records are output via `t.Log`.
+// All log messages with level trace or lower are logged.
+// The returned logger get Shutdown() when the tests completes. The caller should not shut it down.
+func CreateTestLogger(t *testing.T) *Logger {
+	t.Helper()
+
+	logger, err := NewLogger()
+	if err != nil {
+		t.Fatalf("failed create logger %v", err)
+	}
+
+	filter := logr.StdFilter{
+		Lvl:        LvlTrace,
+		Stacktrace: LvlPanic,
+	}
+	formatter := &formatters.Plain{EnableCaller: true}
+	target := targets.NewTestingTarget(t)
+
+	if err := logger.log.Logr().AddTarget(target, "test", filter, formatter, 1000); err != nil {
+		t.Fatalf("failed to add target %v", err)
+	}
+
+	t.Cleanup(func() {
+		err := logger.Shutdown()
+		if err != nil {
+			t.Errorf("failed to shut down test logger %v", err)
+		}
+	})
+
+	return logger
+}
+
+// Buffer provides a thread-safe buffer useful for logging to memory in unit tests.
+type Buffer struct {
+	buf bytes.Buffer
+	mux sync.Mutex
+}
+
+func (b *Buffer) Read(p []byte) (n int, err error) {
+	b.mux.Lock()
+	defer b.mux.Unlock()
+	return b.buf.Read(p)
+}
+func (b *Buffer) Write(p []byte) (n int, err error) {
+	b.mux.Lock()
+	defer b.mux.Unlock()
+	return b.buf.Write(p)
+}
+func (b *Buffer) String() string {
+	b.mux.Lock()
+	defer b.mux.Unlock()
+	return b.buf.String()
+}