// resolveCharmURL returns a resolved charm URL, given a charm location string.
// If the series is not resolved, the environment default-series is used, or if
// not set, the series is resolved with the state server.
func resolveCharmURL(url string, client *api.Client, conf *config.Config) (*charm.URL, error) {
ref, err := charm.ParseReference(url)
if err != nil {
return nil, err
}
// If series is not set, use configured default series
if ref.Series == "" {
if defaultSeries, ok := conf.DefaultSeries(); ok {
ref.Series = defaultSeries
}
}
if ref.Series != "" {
return ref.URL("")
}
// Otherwise, look up the best supported series for this charm
if ref.Schema != "local" {
return client.ResolveCharm(ref)
}
possibleURL := *ref
possibleURL.Series = "precise"
logger.Errorf("The series is not specified in the environment (default-series) or with the charm. Did you mean:\n\t%s", &possibleURL)
return nil, fmt.Errorf("cannot resolve series for charm: %q", ref)
}