Feature: add no-cache cli flag for fetch subcommand for skipping the system cached packages

pkg/fetch/cache_strategy.go

@@ -17,7 +17,8 @@ const (
 type CacheStrategy int
 
 // determinePackageCacheStrategy determines package cache strategy via package filesystem path.
-func determinePackageCacheStrategy(packageMeta pkg.PackageMeta, projectRoot string) (error, CacheStrategy) {
+// noCache: dont use the global cache
+func determinePackageCacheStrategy(packageMeta pkg.PackageMeta, projectRoot string, noCache bool) (error, CacheStrategy) {
 	pkgCachePath := packageMeta.HomeCacheSrcPath() // package global cache dir
 	pkgVendorPath := packageMeta.VendorSrcPath(projectRoot)
 
@@ -28,7 +29,10 @@ func determinePackageCacheStrategy(packageMeta pkg.PackageMeta, projectRoot stri
 				return nil, CacheStrategyDownloadFromRemote
 			}
 			return err, CacheStrategySkip
-		} else { // vendor src does not exist, but global cache exist.
+		} else {         // vendor src does not exist, but global cache exist.
+			if noCache { // if noCache, directly download. Don't use global cache.
+				return err, CacheStrategyDownloadFromRemote
+			}
 			return nil, CacheStrategyCopyFromGlobalCache
 		}
 	} else if err != nil { // other error for vendor src stat

pkg/fetch/fetch.go

@@ -43,6 +43,7 @@ func init() {
 	fetchCommand.FlagSet.StringVar(&f.PkgHome, "p", pwd, "absolute or relative path for file "+pkg.PkgFileName)
 	fetchCommand.FlagSet.StringVar(&f.CMakeFindPackageOption, "cmake-find-package-arg", "NO_DEFAULT_PATH", "global options for find_package when generating file pkg.dep.cmake")
 	fetchCommand.FlagSet.StringVar(&f.FeaturesOption, "features", DefaultFeatureName, "Comma separated list of features to activate. e.g. --features=foo,bar")
+	fetchCommand.FlagSet.BoolVar(&f.NoCache, "no-cache", false, "Don't use the system cache. Directly download from the Internet")
 	// todo make pkgHome abs path anyway.
 	fetchCommand.FlagSet.Usage = fetchCommand.Usage // use default usage provided by cmds.Command.
 	fetchCommand.Runner = &f
@@ -55,6 +56,7 @@ type fetch struct {
 	FeaturesOption         string   // cli `feature` string
 	FeatureList            []string // feature list parsed from cli option.
 	MirrorConfPath         string   // the file path of repo mirror file.
+	NoCache                bool     // download package without using global cache
 	DepTree                pkg.DependencyTree
 	Auth                   map[string]conf.Auth
 	GlobalReplace          map[string]string
@@ -329,7 +331,7 @@ func (f *fetch) dlPackagesDepSrc(pkgLock *map[string]string, featPkgList []strin
 		srcDes := context.HomeCacheSrcPath()
 		vendorSrcDes := context.VendorSrcPath(f.PkgHome)
 
-		err, strategy := determinePackageCacheStrategy(context, f.PkgHome)
+		err, strategy := determinePackageCacheStrategy(context, f.PkgHome, f.NoCache)
 		if err != nil {
 			return nil, err
 		}

pkg/fetch/src_dl.go

@@ -105,10 +105,8 @@ func filesSrc(srcDes, packageName, baseUrl string, files map[string]string) erro
 		}
 	}
 
-	// move dir from temp dir to real source file location.
-	log.WithFields(log.Fields{"pkg": packageName, "temp path": tempPath, "src path": srcDes}).
-		Debugln("move dependency from temporary directory to source path.")
-	if err := os.Rename(tempPath, srcDes); err != nil {
+	// move dir from temp dir to real source file location in postDownloadStep.
+	if err := postDownloadStep(packageName, tempPath, srcDes); err != nil {
 		return err
 	}
 	return nil
@@ -215,10 +213,8 @@ func archiveSrc(archiveType string, srcPath string, packageName string, remoteUr
 		"storage": tempPath,
 	}).Println("finished extracting package.")
 
-	// move dir from temp dir to real source file location.
-	log.WithFields(log.Fields{"pkg": packageName, "temp path": tempPath, "src path": srcPath}).
-		Debugln("move dependency from temporary directory to source path.")
-	if err := os.Rename(tempPath, srcPath); err != nil {
+	// move dir from temp dir to real source file location in postDownloadStep.
+	if err := postDownloadStep(packageName, tempPath, srcPath); err != nil {
 		return err
 	}
 	return nil
@@ -326,19 +322,8 @@ func gitSrc(auths map[string]conf.Auth, packageCacheDir, packagePath, packageUrl
 			return err
 		}
 
-		// move temp dir to global home source dir
-		log.WithFields(log.Fields{"pkg": packagePath, "temp path": tempPath, "src path": packageCacheDir}).
-			Debugln("move dependency from temporary directory to source path.")
-		// create parent dir first and then perform move.
-		if srcParentDir, err := pkg.GetCachedPackageSrcPath(packagePath, ".draft"); err != nil {
+		if err := postDownloadStep(packagePath, tempPath, packageCacheDir); err != nil {
 			return err
-		} else {
-			if err := os.MkdirAll(srcParentDir, 0744); err != nil {
-				return err
-			}
-			if err := os.Rename(tempPath, packageCacheDir); err != nil {
-				return err
-			}
 		}
 	}
 
@@ -349,3 +334,27 @@ func gitSrc(auths map[string]conf.Auth, packageCacheDir, packagePath, packageUrl
 
 	return nil
 }
+
+func postDownloadStep(packageName, tempPath, packageCacheDir string) error {
+	// move temp dir to global home source dir
+	log.WithFields(log.Fields{"pkg": packageName, "temp path": tempPath, "src path": packageCacheDir}).
+		Debugln("move dependency from temporary directory to source path.")
+	// create parent dir first and then perform move.
+	if srcParentDir, err := pkg.GetCachedPackageSrcPath(packageName, ".draft"); err != nil {
+		return err
+	} else {
+		if err := os.MkdirAll(srcParentDir, 0744); err != nil {
+			return err
+		}
+		// remove the old package directory if possible
+		if err := os.RemoveAll(packageCacheDir); err != nil {
+			return err
+		}
+
+		// perform renaming: move from tem dir to the system cache dir.
+		if err := os.Rename(tempPath, packageCacheDir); err != nil {
+			return err
+		}
+	}
+	return nil
+}