refactor logging. Details:

- packages use tagged logger sending log messages to shared (process-wide) logging engine
- log writers (interface ethlog.LogSystem) can be added to the logging engine by wrappers/guis/clients
- shared logging engine dispatching to multiple log systems
- log level can be set separately per log system
- async logging thread: logging IO does not block main thread
- log messages are synchronously stringified to avoid incorrectly logging of changed states
- README.md
- loggers_test

1 files changed, 115 insertions, 0 deletions

diff --git a/ethlog/loggers_test.go b/ethlog/loggers_test.go
new file mode 100644
index 000000000..c33082012
--- /dev/null
+++ b/ethlog/loggers_test.go
@@ -0,0 +1,115 @@
+package ethlog
+
+import (
+  "testing"
+  "fmt"
+  "io/ioutil"
+  "os"
+)
+
+type TestLogSystem struct {
+  Output string
+  level  LogLevel
+}
+
+func (t *TestLogSystem) Println(v ...interface{}) {
+  t.Output += fmt.Sprintln(v...)
+}
+
+func (t *TestLogSystem) Printf(format string, v ...interface{}) {
+  t.Output += fmt.Sprintf(format, v...)
+}
+
+func (t *TestLogSystem) SetLogLevel(i LogLevel) {
+  t.level = i
+}
+
+func (t *TestLogSystem) GetLogLevel() LogLevel {
+  return t.level
+}
+
+func quote(s string) string {
+  return fmt.Sprintf("'%s'", s)
+}
+
+func TestLoggerPrintln(t *testing.T) {
+  logger := NewLogger("TEST")
+  testLogSystem := &TestLogSystem{level: WarnLevel}
+  AddLogSystem(testLogSystem)
+  logger.Errorln("error")
+  logger.Warnln("warn")
+  logger.Infoln("info")
+  logger.Debugln("debug")
+  Flush()
+  output := testLogSystem.Output
+  fmt.Println(quote(output))
+  if output != "[TEST] error\n[TEST] warn\n" {
+    t.Error("Expected logger output '[TEST] error\\n[TEST] warn\\n', got ", quote(testLogSystem.Output))
+  }
+}
+
+func TestLoggerPrintf(t *testing.T) {
+  logger := NewLogger("TEST")
+  testLogSystem := &TestLogSystem{level: WarnLevel}
+  AddLogSystem(testLogSystem)
+  logger.Errorf("error to %v\n", *testLogSystem)
+  logger.Warnf("warn")
+  logger.Infof("info")
+  logger.Debugf("debug")
+  Flush()
+  output := testLogSystem.Output
+  fmt.Println(quote(output))
+  if output != "[TEST] error to { 2}\n[TEST] warn" {
+    t.Error("Expected logger output '[TEST] error to { 2}\\n[TEST] warn', got ", quote(testLogSystem.Output))
+  }
+}
+
+func TestMultipleLogSystems(t *testing.T) {
+  logger := NewLogger("TEST")
+  testLogSystem0 := &TestLogSystem{level: ErrorLevel}
+  testLogSystem1 := &TestLogSystem{level: WarnLevel}
+  AddLogSystem(testLogSystem0)
+  AddLogSystem(testLogSystem1)
+  logger.Errorln("error")
+  logger.Warnln("warn")
+  Flush()
+  output0 := testLogSystem0.Output
+  output1 := testLogSystem1.Output
+  if output0 != "[TEST] error\n" {
+    t.Error("Expected logger 0 output '[TEST] error\\n', got ", quote(testLogSystem0.Output))
+  }
+  if output1 != "[TEST] error\n[TEST] warn\n" {
+    t.Error("Expected logger 1 output '[TEST] error\\n[TEST] warn\\n', got ", quote(testLogSystem1.Output))
+  }
+}
+
+func TestFileLogSystem(t *testing.T) {
+  logger := NewLogger("TEST")
+  filename := "test.log"
+  file, _ := os.OpenFile(filename, os.O_RDWR|os.O_CREATE, os.ModePerm)
+  testLogSystem := NewStdLogSystem(file, 0, WarnLevel)
+  AddLogSystem(testLogSystem)
+  logger.Errorf("error to %s\n", filename)
+  logger.Warnln("warn")
+  Flush()
+  contents, _ :=  ioutil.ReadFile(filename)
+  output := string(contents)
+  fmt.Println(quote(output))
+  if output != "[TEST] error to test.log\n[TEST] warn\n" {
+    t.Error("Expected contents of file 'test.log': '[TEST] error to test.log\\n[TEST] warn\\n', got ", quote(output))
+  } else {
+    os.Remove(filename)
+  }
+}
+
+func TestNoLogSystem(t *testing.T) {
+  logger := NewLogger("TEST")
+  logger.Warnln("warn")
+  Flush()
+}
+
+
+
+
+
+