Files
windows_exporter/internal/log/eventlog/eventlog_internal_test.go
T

124 lines
2.9 KiB
Go

// SPDX-License-Identifier: Apache-2.0
//
// Copyright The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//go:build windows
package eventlog
import (
"os"
"sync"
"testing"
"github.com/stretchr/testify/require"
)
// fakeEventLog records the events it receives and fails every use after Close,
// like a closed event log handle.
type fakeEventLog struct {
mu sync.Mutex
events []string
closes int
}
func (f *fakeEventLog) record(level, msg string) error {
f.mu.Lock()
defer f.mu.Unlock()
if f.closes > 0 {
return os.ErrInvalid
}
f.events = append(f.events, level+": "+msg)
return nil
}
func (f *fakeEventLog) Info(_ uint32, msg string) error { return f.record("info", msg) }
func (f *fakeEventLog) Warning(_ uint32, msg string) error { return f.record("warning", msg) }
func (f *fakeEventLog) Error(_ uint32, msg string) error { return f.record("error", msg) }
func (f *fakeEventLog) Close() error {
f.mu.Lock()
defer f.mu.Unlock()
f.closes++
return nil
}
func TestWriterLevels(t *testing.T) {
t.Parallel()
handle := &fakeEventLog{}
writer := &Writer{handle: handle}
for _, line := range []string{
"time=2026-10-15T14:03:05Z level=INFO msg=started\n",
"time=2026-10-15T14:03:05Z level=WARN msg=slow\n",
"time=2026-10-15T14:03:05Z level=ERROR msg=failed\n",
} {
n, err := writer.Write([]byte(line))
require.NoError(t, err)
require.Equal(t, len(line), n)
}
require.Equal(t, []string{"info: msg=started", "warning: msg=slow", "error: msg=failed"}, handle.events)
}
func TestWriterWriteAfterClose(t *testing.T) {
t.Parallel()
handle := &fakeEventLog{}
writer := &Writer{handle: handle}
require.NoError(t, writer.Close())
require.NoError(t, writer.Close(), "a second Close is a no-op")
require.Equal(t, 1, handle.closes, "the handle must be closed once")
n, err := writer.Write([]byte("level=INFO msg=late\n"))
require.ErrorIs(t, err, os.ErrClosed)
require.Zero(t, n)
require.Empty(t, handle.events)
}
func TestWriterConcurrentClose(t *testing.T) {
t.Parallel()
handle := &fakeEventLog{}
writer := &Writer{handle: handle}
var wg sync.WaitGroup
for range 8 {
wg.Go(func() {
for range 100 {
// A write either reaches the open handle or fails with os.ErrClosed.
if _, err := writer.Write([]byte("level=INFO msg=x\n")); err != nil {
require.ErrorIs(t, err, os.ErrClosed)
}
}
})
}
wg.Go(func() {
require.NoError(t, writer.Close())
})
wg.Wait()
require.Equal(t, 1, handle.closes)
}