* move ./*.go files into ./home/ directory

home/upgrade.go

@@ -0,0 +1,194 @@
+package home
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+
+	"github.com/AdguardTeam/golibs/file"
+	"github.com/AdguardTeam/golibs/log"
+	yaml "gopkg.in/yaml.v2"
+)
+
+const currentSchemaVersion = 3 // used for upgrading from old configs to new config
+
+// Performs necessary upgrade operations if needed
+func upgradeConfig() error {
+	// read a config file into an interface map, so we can manipulate values without losing any
+	diskConfig := map[string]interface{}{}
+	body, err := readConfigFile()
+	if err != nil {
+		return err
+	}
+
+	err = yaml.Unmarshal(body, &diskConfig)
+	if err != nil {
+		log.Printf("Couldn't parse config file: %s", err)
+		return err
+	}
+
+	schemaVersionInterface, ok := diskConfig["schema_version"]
+	log.Tracef("got schema version %v", schemaVersionInterface)
+	if !ok {
+		// no schema version, set it to 0
+		schemaVersionInterface = 0
+	}
+
+	schemaVersion, ok := schemaVersionInterface.(int)
+	if !ok {
+		err = fmt.Errorf("configuration file contains non-integer schema_version, abort")
+		log.Println(err)
+		return err
+	}
+
+	if schemaVersion == currentSchemaVersion {
+		// do nothing
+		return nil
+	}
+
+	return upgradeConfigSchema(schemaVersion, &diskConfig)
+}
+
+// Upgrade from oldVersion to newVersion
+func upgradeConfigSchema(oldVersion int, diskConfig *map[string]interface{}) error {
+	switch oldVersion {
+	case 0:
+		err := upgradeSchema0to3(diskConfig)
+		if err != nil {
+			return err
+		}
+	case 1:
+		err := upgradeSchema1to3(diskConfig)
+		if err != nil {
+			return err
+		}
+	case 2:
+		err := upgradeSchema2to3(diskConfig)
+		if err != nil {
+			return err
+		}
+	default:
+		err := fmt.Errorf("configuration file contains unknown schema_version, abort")
+		log.Println(err)
+		return err
+	}
+
+	configFile := config.getConfigFilename()
+	body, err := yaml.Marshal(diskConfig)
+	if err != nil {
+		log.Printf("Couldn't generate YAML file: %s", err)
+		return err
+	}
+
+	config.fileData = body
+	err = file.SafeWrite(configFile, body)
+	if err != nil {
+		log.Printf("Couldn't save YAML config: %s", err)
+		return err
+	}
+
+	return nil
+}
+
+// The first schema upgrade:
+// No more "dnsfilter.txt", filters are now kept in data/filters/
+func upgradeSchema0to1(diskConfig *map[string]interface{}) error {
+	log.Printf("%s(): called", _Func())
+
+	dnsFilterPath := filepath.Join(config.ourWorkingDir, "dnsfilter.txt")
+	if _, err := os.Stat(dnsFilterPath); !os.IsNotExist(err) {
+		log.Printf("Deleting %s as we don't need it anymore", dnsFilterPath)
+		err = os.Remove(dnsFilterPath)
+		if err != nil {
+			log.Printf("Cannot remove %s due to %s", dnsFilterPath, err)
+			// not fatal, move on
+		}
+	}
+
+	(*diskConfig)["schema_version"] = 1
+
+	return nil
+}
+
+// Second schema upgrade:
+// coredns is now dns in config
+// delete 'Corefile', since we don't use that anymore
+func upgradeSchema1to2(diskConfig *map[string]interface{}) error {
+	log.Printf("%s(): called", _Func())
+
+	coreFilePath := filepath.Join(config.ourWorkingDir, "Corefile")
+	if _, err := os.Stat(coreFilePath); !os.IsNotExist(err) {
+		log.Printf("Deleting %s as we don't need it anymore", coreFilePath)
+		err = os.Remove(coreFilePath)
+		if err != nil {
+			log.Printf("Cannot remove %s due to %s", coreFilePath, err)
+			// not fatal, move on
+		}
+	}
+
+	if _, ok := (*diskConfig)["dns"]; !ok {
+		(*diskConfig)["dns"] = (*diskConfig)["coredns"]
+		delete((*diskConfig), "coredns")
+	}
+	(*diskConfig)["schema_version"] = 2
+
+	return nil
+}
+
+// Third schema upgrade:
+// Bootstrap DNS becomes an array
+func upgradeSchema2to3(diskConfig *map[string]interface{}) error {
+	log.Printf("%s(): called", _Func())
+
+	// Let's read dns configuration from diskConfig
+	dnsConfig, ok := (*diskConfig)["dns"]
+	if !ok {
+		return fmt.Errorf("no DNS configuration in config file")
+	}
+
+	// Convert interface{} to map[string]interface{}
+	newDNSConfig := make(map[string]interface{})
+
+	switch v := dnsConfig.(type) {
+	case map[interface{}]interface{}:
+		for k, v := range v {
+			newDNSConfig[fmt.Sprint(k)] = v
+		}
+	default:
+		return fmt.Errorf("DNS configuration is not a map")
+	}
+
+	// Replace bootstrap_dns value filed with new array contains old bootstrap_dns inside
+	if bootstrapDNS, ok := (newDNSConfig)["bootstrap_dns"]; ok {
+		newBootstrapConfig := []string{fmt.Sprint(bootstrapDNS)}
+		(newDNSConfig)["bootstrap_dns"] = newBootstrapConfig
+		(*diskConfig)["dns"] = newDNSConfig
+	} else {
+		return fmt.Errorf("no bootstrap DNS in DNS config")
+	}
+
+	// Bump schema version
+	(*diskConfig)["schema_version"] = 3
+
+	return nil
+}
+
+// jump three schemas at once -- this time we just do it sequentially
+func upgradeSchema0to3(diskConfig *map[string]interface{}) error {
+	err := upgradeSchema0to1(diskConfig)
+	if err != nil {
+		return err
+	}
+
+	return upgradeSchema1to3(diskConfig)
+}
+
+// jump two schemas at once -- this time we just do it sequentially
+func upgradeSchema1to3(diskConfig *map[string]interface{}) error {
+	err := upgradeSchema1to2(diskConfig)
+	if err != nil {
+		return err
+	}
+
+	return upgradeSchema2to3(diskConfig)
+}