Refactor doctor (#12264)

* Refactor Logger

Refactor Logger to make a logger interface and make it possible to
wrap loggers for specific purposes.

* Refactor Doctor

    Move the gitea doctor functions into its own module.
    Use a logger for its messages instead of returning a results string[]

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Update modules/doctor/misc.go

Co-authored-by: 6543 <6543@obermui.de>

* Update modules/doctor/misc.go

Co-authored-by: 6543 <6543@obermui.de>

Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>

modules/doctor/doctor.go

@@ -0,0 +1,105 @@
+// Copyright 2020 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package doctor
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+
+	"code.gitea.io/gitea/models"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting"
+)
+
+// Check represents a Doctor check
+type Check struct {
+	Title                      string
+	Name                       string
+	IsDefault                  bool
+	Run                        func(logger log.Logger, autofix bool) error
+	AbortIfFailed              bool
+	SkipDatabaseInitialization bool
+	Priority                   int
+}
+
+type wrappedLevelLogger struct {
+	log.LevelLogger
+}
+
+func (w *wrappedLevelLogger) Log(skip int, level log.Level, format string, v ...interface{}) error {
+	return w.LevelLogger.Log(
+		skip+1,
+		level,
+		" - %s "+format,
+		append(
+			[]interface{}{
+				log.NewColoredValueBytes(
+					fmt.Sprintf("[%s]", strings.ToUpper(level.String()[0:1])),
+					level.Color()),
+			}, v...)...)
+}
+
+func initDBDisableConsole(disableConsole bool) error {
+	setting.NewContext()
+	setting.InitDBConfig()
+
+	setting.NewXORMLogService(disableConsole)
+	if err := models.SetEngine(); err != nil {
+		return fmt.Errorf("models.SetEngine: %v", err)
+	}
+	return nil
+}
+
+// Checks is the list of available commands
+var Checks []*Check
+
+// RunChecks runs the doctor checks for the provided list
+func RunChecks(logger log.Logger, autofix bool, checks []*Check) error {
+	wrappedLogger := log.LevelLoggerLogger{
+		LevelLogger: &wrappedLevelLogger{logger},
+	}
+
+	dbIsInit := false
+	for i, check := range checks {
+		if !dbIsInit && !check.SkipDatabaseInitialization {
+			// Only open database after the most basic configuration check
+			setting.EnableXORMLog = false
+			if err := initDBDisableConsole(true); err != nil {
+				logger.Error("Error whilst initializing the database: %v", err)
+				logger.Error("Check if you are using the right config file. You can use a --config directive to specify one.")
+				return nil
+			}
+			dbIsInit = true
+		}
+		logger.Info("[%d] %s", log.NewColoredIDValue(i+1), check.Title)
+		logger.Flush()
+		if err := check.Run(&wrappedLogger, autofix); err != nil {
+			if check.AbortIfFailed {
+				logger.Critical("FAIL")
+				return err
+			}
+			logger.Error("ERROR")
+		} else {
+			logger.Info("OK")
+			logger.Flush()
+		}
+	}
+	return nil
+}
+
+// Register registers a command with the list
+func Register(command *Check) {
+	Checks = append(Checks, command)
+	sort.SliceStable(Checks, func(i, j int) bool {
+		if Checks[i].Priority == Checks[j].Priority {
+			return Checks[i].Name < Checks[j].Name
+		}
+		if Checks[i].Priority == 0 {
+			return false
+		}
+		return Checks[i].Priority < Checks[j].Priority
+	})
+}