[forwardport] refactor(oonimkall): merge internal/task into oonimkall (#617) (#618)

This diff forward ports bc4b9f1ea89158bfa7b7a80ae59a90b43c784ed2 to `master`.

See https://github.com/ooni/probe/issues/1903

pkg/oonimkall/internal/tasks/chanlogger.go

@@ -1,87 +0,0 @@
-package tasks
-
-import (
-	"fmt"
-)
-
-// ChanLogger is a logger targeting a channel
-type ChanLogger struct {
-	emitter    *EventEmitter
-	hasdebug   bool
-	hasinfo    bool
-	haswarning bool
-	out        chan<- *Event
-}
-
-// Debug implements Logger.Debug
-func (cl *ChanLogger) Debug(msg string) {
-	if cl.hasdebug {
-		cl.emitter.Emit("log", EventLog{
-			LogLevel: "DEBUG",
-			Message:  msg,
-		})
-	}
-}
-
-// Debugf implements Logger.Debugf
-func (cl *ChanLogger) Debugf(format string, v ...interface{}) {
-	if cl.hasdebug {
-		cl.Debug(fmt.Sprintf(format, v...))
-	}
-}
-
-// Info implements Logger.Info
-func (cl *ChanLogger) Info(msg string) {
-	if cl.hasinfo {
-		cl.emitter.Emit("log", EventLog{
-			LogLevel: "INFO",
-			Message:  msg,
-		})
-	}
-}
-
-// Infof implements Logger.Infof
-func (cl *ChanLogger) Infof(format string, v ...interface{}) {
-	if cl.hasinfo {
-		cl.Info(fmt.Sprintf(format, v...))
-	}
-}
-
-// Warn implements Logger.Warn
-func (cl *ChanLogger) Warn(msg string) {
-	if cl.haswarning {
-		cl.emitter.Emit("log", EventLog{
-			LogLevel: "WARNING",
-			Message:  msg,
-		})
-	}
-}
-
-// Warnf implements Logger.Warnf
-func (cl *ChanLogger) Warnf(format string, v ...interface{}) {
-	if cl.haswarning {
-		cl.Warn(fmt.Sprintf(format, v...))
-	}
-}
-
-// NewChanLogger creates a new ChanLogger instance.
-func NewChanLogger(emitter *EventEmitter, logLevel string,
-	out chan<- *Event) *ChanLogger {
-	cl := &ChanLogger{
-		emitter: emitter,
-		out:     out,
-	}
-	switch logLevel {
-	case "DEBUG", "DEBUG2":
-		cl.hasdebug = true
-		fallthrough
-	case "INFO":
-		cl.hasinfo = true
-		fallthrough
-	case "ERR", "WARNING":
-		fallthrough
-	default:
-		cl.haswarning = true
-	}
-	return cl
-}