feat(migration): OneToTwo basic implementation

config/migrate/migrate.go

@@ -2,21 +2,32 @@
 package migrate
 
 import (
+ "fmt"
+ "os"
+ "path/filepath"
+
  "github.com/qri-io/ioes"
  "github.com/qri-io/qri/config"
+ qerr "github.com/qri-io/qri/errors"
 )
 
 // RunMigrations checks to see if any migrations runs them
-func RunMigrations(streams ioes.IOStreams, cfg *config.Config) (migrated bool, err error) {
+func RunMigrations(streams ioes.IOStreams, cfg *config.Config) (err error) {
  if cfg.Revision != config.CurrentConfigRevision {
  streams.PrintErr("migrating configuration...")
- if err := ZeroToOne(cfg); err != nil {
- return false, err
+ if cfg.Revision == 0 {
+ if err := ZeroToOne(cfg); err != nil {
+ return err
+ }
+ }
+ if cfg.Revision == 1 {
+ if err := OneToTwo(cfg); err != nil {
+ return err
+ }
  }
  streams.PrintErr("done!\n")
- return true, nil
  }
- return false, nil
+ return nil
 }
 
 // ZeroToOne migrates a configuration from Revision Zero (no revision number) to Revision 1
@@ -49,9 +60,76 @@ func ZeroToOne(cfg *config.Config) error {
  }
 
  cfg.Revision = 1
+
+ if err := safeWriteConfig(cfg); err != nil {
+ rollbackConfigWrite(cfg)
+ return err
+ }
+
  return nil
 }
 
+// OneToTwo migrates a configuration from Revision 1 to Revision 2
+func OneToTwo(cfg *config.Config) error {
+
+ // TODO(ramfox): qfs migration
+
+ // TODO(arqu): config migration
+ // if err := oneToTwoConfig(cfg); err != nil {
+ // return err
+ // }
+ // cfg.Revision = 2
+ // if err := cfg.Validate(); err != nil {
+ // return qerr.New(err, "config is invalid")
+ // }
+ // TODO(arqu): config write/rollback
+ // if err := safeWriteConfig(cfg); err != nil {
+ // rollbackConfigWrite(cfg)
+ // return err
+ // }
+
+ // TODO(ramfox): remove original ipfs repo after all migrations were successful
+
+ return nil
+}
+
+func oneToTwoConfig(cfg *config.Config) error {
+ return nil
+}
+
+func rollbackConfigWrite(cfg *config.Config) {
+ cfgPath := cfg.Path()
+ if len(cfgPath) == 0 {
+ return
+ }
+ tmpCfgPath := getTmpConfigFilepath(cfgPath)
+ if _, err := os.Stat(tmpCfgPath); !os.IsNotExist(err) {
+ os.Remove(tmpCfgPath)
+ }
+}
+
+func safeWriteConfig(cfg *config.Config) error {
+ cfgPath := cfg.Path()
+ if len(cfgPath) == 0 {
+ return qerr.New(fmt.Errorf("invalid path"), "could not determine config path")
+ }
+ tmpCfgPath := getTmpConfigFilepath(cfgPath)
+ if err := cfg.WriteToFile(tmpCfgPath); err != nil {
+ return qerr.New(err, fmt.Sprintf("could not write config to path %s", tmpCfgPath))
+ }
+ if err := os.Rename(tmpCfgPath, cfgPath); err != nil {
+ return qerr.New(err, fmt.Sprintf("could not write config to path %s", cfgPath))
+ }
+
+ return nil
+}
+
+func getTmpConfigFilepath(cfgPath string) string {
+ cfgDir := filepath.Dir(cfgPath)
+ tmpCfgPath := filepath.Join(cfgDir, "config_updated.yaml")
+ return tmpCfgPath
+}
+
 func delIdx(i int, sl []string) []string {
  if i < len(sl)-1 {
  return append(sl[:i], sl[i+1:]...)

dsref/resolve_test.go

@@ -6,4 +6,4 @@ import (
 
 func TestParallelResolver(t *testing.T) {
  t.Skip("TODO(b5)")
-}
+}

lib/lib.go

@@ -184,14 +184,11 @@ func OptCheckConfigMigrations(cfgPath string) Option {
  return fmt.Errorf("no config file to check for migrations")
  }
 
- migrated, err := migrate.RunMigrations(o.Streams, o.Cfg)
+ err := migrate.RunMigrations(o.Streams, o.Cfg)
  if err != nil {
  return err
  }
 
- if migrated {
- return o.Cfg.WriteToFile(cfgPath)
- }
  return nil
  }
 }