add clean subcommand

related issues: #48, #58

clean.go

@@ -0,0 +1,110 @@
+// Copyright (c) 2015, Daniel Martí <mvdan@mvdan.cc>
+// See LICENSE for licensing information
+
+package main
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"syscall"
+)
+
+var cmdClean = &Command{
+	UsageLine: "clean",
+	Short:     "Clean index and/or cache",
+	Long: `
+Clean index and/or cache.
+The index basically contains information about available APKs to download.
+The cache is where all downloaded APKs are cached.
+Usage:
+
+	$ fdroidcl clean
+	$ fdroidcl clean index
+	$ fdroidcl clean cache
+`[1:],
+}
+
+func init() {
+	cmdClean.Run = runClean
+}
+
+func runClean(args []string) error {
+	if len(args) > 1 {
+		return fmt.Errorf("wrong amount of arguments")
+	}
+	if len(args) == 1 && (args[0] != "index" && args[0] != "cache") {
+		return fmt.Errorf("pass either index or cache as parameter, or no parameter at all")
+	}
+	if len(args) == 0 || args[0] == "index" {
+		err := cleanIndex()
+		if err != nil {
+			return err
+		}
+	}
+	if len(args) == 0 || args[0] == "cache" {
+		err := cleanCache()
+		if err != nil {
+			return err
+		}
+	}
+	if len(args) == 1 {
+		fmt.Printf("Cleaned %s.\n", args[0])
+	} else {
+		fmt.Println("Cleaned index and cache.")
+	}
+	return nil
+}
+
+func cleanIndex() error {
+	cachePath := filepath.Join(mustCache(), "cache-gob")
+	err := removeFile(cachePath)
+	if err != nil {
+		return err
+	}
+	err = removeGlob(mustData() + "/*.jar")
+	if err != nil {
+		return err
+	}
+	err = removeGlob(mustData() + "/*.jar-etag")
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func cleanCache() error {
+	apksDir := subdir(mustCache(), "apks")
+	err := os.RemoveAll(apksDir)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func removeFile(path string) error {
+	err := os.Remove(path)
+	if err != nil {
+		e, ok := err.(*os.PathError)
+		if ok && e.Err == syscall.ENOENT {
+			// The file didn't exist, ignore
+		} else {
+			return err
+		}
+	}
+	return nil
+}
+
+func removeGlob(glob string) error {
+	matches, err := filepath.Glob(glob)
+	if err != nil {
+		return err
+	}
+	for _, value := range matches {
+		err := removeFile(value)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}

main.go

@@ -169,6 +169,7 @@ var commands = []*Command{
 	cmdList,
 	cmdDefaults,
 	cmdVersion,
+	cmdClean,
 }
 
 var cmdVersion = &Command{