feat(miniooni): optionally log using emojis (#932)

As silly as it seems, emojis help _a lot_ when eyeballing logs
to quickly identify unexpected lines.

I'm doing this work as part of https://github.com/ooni/probe/issues/2257

internal/cmd/miniooni/logging.go

@@ -1,35 +0,0 @@
-package main
-
-//
-// Logging functionality
-//
-
-import (
-	"fmt"
-	"io"
-	"time"
-
-	"github.com/apex/log"
-)
-
-// logStartTime is the time when we started logging
-var logStartTime = time.Now()
-
-// logHandler implements the log handler required by github.com/apex/log
-type logHandler struct {
-	// Writer is the underlying writer
-	io.Writer
-}
-
-var _ log.Handler = &logHandler{}
-
-// HandleLog implements log.Handler
-func (h *logHandler) HandleLog(e *log.Entry) (err error) {
-	s := fmt.Sprintf("[%14.6f] <%s> %s", time.Since(logStartTime).Seconds(), e.Level, e.Message)
-	if len(e.Fields) > 0 {
-		s += fmt.Sprintf(": %+v", e.Fields)
-	}
-	s += "\n"
-	_, err = h.Writer.Write([]byte(s))
-	return
-}

internal/cmd/miniooni/main.go

@@ -15,6 +15,7 @@ import (
 	"github.com/ooni/probe-cli/v3/internal/engine"
 	"github.com/ooni/probe-cli/v3/internal/humanize"
 	"github.com/ooni/probe-cli/v3/internal/legacy/assetsdir"
+	"github.com/ooni/probe-cli/v3/internal/logx"
 	"github.com/ooni/probe-cli/v3/internal/model"
 	"github.com/ooni/probe-cli/v3/internal/registry"
 	"github.com/ooni/probe-cli/v3/internal/runtimex"
@@ -25,6 +26,7 @@ import (
 // Options contains the options you can set from the CLI.
 type Options struct {
 	Annotations      []string
+	Emoji            bool
 	ExtraOptions     []string
 	HomeDir          string
 	Inputs           []string
@@ -64,6 +66,13 @@ func main() {
 		"add KEY=VALUE annotation to the report (can be repeated multiple times)",
 	)
 
+	flags.BoolVar(
+		&globalOptions.Emoji,
+		"emoji",
+		false,
+		"whether to use emojis when logging",
+	)
+
 	flags.StringVar(
 		&globalOptions.HomeDir,
 		"home",
@@ -266,7 +275,9 @@ func MainWithConfiguration(experimentName string, currentOptions *Options) {
 		currentOptions.Proxy = fmt.Sprintf("%s:///", currentOptions.Tunnel)
 	}
 
-	logger := &log.Logger{Level: log.InfoLevel, Handler: &logHandler{Writer: os.Stderr}}
+	logHandler := logx.NewHandlerWithDefaultSettings()
+	logHandler.Emoji = currentOptions.Emoji
+	logger := &log.Logger{Level: log.InfoLevel, Handler: logHandler}
 	if currentOptions.Verbose {
 		logger.Level = log.DebugLevel
 	}