Index fixes and performance improvements (fixes #223, #224)

- Fixed creation of duplicate index entries when importing from CurseForge (fixes #224)
- Automatically remove duplicates in index
- Fixed `packwiz serve` with a custom `--pack-root` argument (fixes #223)
- Fixed `packwiz serve` with a custom index.toml location
- Cleaned up internal serving code, added comments and better errors
- Refactored path handling code
- Improved refreshing/exporting performance
- Factored out duplicated exporting logic
- Replaced GetAllMods calls with cleaner LoadAllMods calls and made the former private
- Improved variable names in update command
- Improved handling of aliassed files
- Changed CheckUpdate to take references to metadata
- Removed the ability to use an absolute path to the index file (that probably didn't work anyway)
- Behaviour change: order of entries in exported files may be random

curseforge/export.go

@@ -10,7 +10,6 @@ import (
 	"github.com/spf13/cobra"
 	"github.com/spf13/viper"
 	"os"
-	"path/filepath"
 	"strconv"
 )
 
@@ -59,9 +58,6 @@ var exportCmd = &cobra.Command{
 			os.Exit(1)
 		}
 
-		// TODO: should index just expose indexPath itself, through a function?
-		indexPath := filepath.Join(filepath.Dir(viper.GetString("pack-file")), filepath.FromSlash(pack.Index.File))
-
 		fmt.Println("Reading external files...")
 		mods, err := index.LoadAllMods()
 		if err != nil {
@@ -139,7 +135,7 @@ var exportCmd = &cobra.Command{
 			cmdshared.ListManualDownloads(session)
 
 			for dl := range session.StartDownloads() {
-				_ = cmdshared.AddToZip(dl, exp, "overrides", indexPath)
+				_ = cmdshared.AddToZip(dl, exp, "overrides", &index)
 			}
 
 			err = session.SaveIndex()
@@ -173,31 +169,7 @@ var exportCmd = &cobra.Command{
 			os.Exit(1)
 		}
 
-		i = 0
-		for _, v := range index.Files {
-			if !v.MetaFile {
-				// Save all non-metadata files into the zip
-				path, err := filepath.Rel(filepath.Dir(indexPath), index.GetFilePath(v))
-				if err != nil {
-					fmt.Printf("Error resolving file: %s\n", err.Error())
-					// TODO: exit(1)?
-					continue
-				}
-				file, err := exp.Create(filepath.ToSlash(filepath.Join("overrides", path)))
-				if err != nil {
-					fmt.Printf("Error creating file: %s\n", err.Error())
-					// TODO: exit(1)?
-					continue
-				}
-				err = index.SaveFile(v, file)
-				if err != nil {
-					fmt.Printf("Error copying file: %s\n", err.Error())
-					// TODO: exit(1)?
-					continue
-				}
-				i++
-			}
-		}
+		cmdshared.AddNonMetafileOverrides(&index, exp)
 
 		err = exp.Close()
 		if err != nil {