// Read reads a State from the file. If the file does not exist it returns
// ErrNoStateFile.
func (f *StateFile) Read() (*State, error) {
var st State
if err := utils.ReadYaml(f.path, &st); err != nil {
if os.IsNotExist(err) {
return nil, ErrNoStateFile
}
}
if err := st.validate(); err != nil {
return nil, fmt.Errorf("cannot read charm state at %q: %v", f.path, err)
}
return &st, nil
}
// loadManifest loads, from dataPath, the manifest for the charm identified by the
// identity file at the supplied path within the charm directory.
func (d *manifestDeployer) loadManifest(urlFilePath string) (*charm.URL, set.Strings, error) {
url, err := ReadCharmURL(d.CharmPath(urlFilePath))
if err != nil {
return nil, set.NewStrings(), err
}
name := charm.Quote(url.String())
path := filepath.Join(d.DataPath(manifestsDataPath), name)
manifest := []string{}
err = utils.ReadYaml(path, &manifest)
if os.IsNotExist(err) {
logger.Warningf("manifest not found at %q: files from charm %q may be left unremoved", path, url)
err = nil
}
return url, set.NewStrings(manifest...), err
}