// Run checks to see if there is already an environments.yaml file. In one does not exist already,
// a boilerplate version is created so that the user can edit it to get started.
func (c *InitCommand) Run(context *cmd.Context) error {
out := context.Stdout
config := environs.BoilerplateConfig()
if c.Show {
fmt.Fprint(out, config)
return nil
}
_, err := environs.ReadEnvirons("")
if err == nil && !c.WriteFile {
return errJujuEnvExists
}
if err != nil && !environs.IsNoEnv(err) {
return err
}
filename, err := environs.WriteEnvirons("", config)
if err != nil {
return fmt.Errorf("A boilerplate environment configuration file could not be created: %s", err.Error())
}
fmt.Fprintf(out, "A boilerplate environment configuration file has been written to %s.\n", filename)
fmt.Fprint(out, "Edit the file to configure your juju environment and run bootstrap.\n")
return nil
}
// newAPIFromStore implements the bulk of NewAPIClientFromName
// but is separate for testing purposes.
func newAPIFromStore(envName string, store configstore.Storage, apiOpen apiOpenFunc) (apiState, error) {
// Try to read the default environment configuration file.
// If it doesn't exist, we carry on in case
// there's some environment info for that environment.
// This enables people to copy environment files
// into their .juju/environments directory and have
// them be directly useful with no further configuration changes.
envs, err := environs.ReadEnvirons("")
if err == nil {
if envName == "" {
envName = envs.Default
}
if envName == "" {
return nil, fmt.Errorf("no default environment found")
}
} else if !environs.IsNoEnv(err) {
return nil, err
}
// Try to connect to the API concurrently using two different
// possible sources of truth for the API endpoint. Our
// preference is for the API endpoint cached in the API info,
// because we know that without needing to access any remote
// provider. However, the addresses stored there may no longer
// be current (and the network connection may take a very long
// time to time out) so we also try to connect using information
// found from the provider. We only start to make that
// connection after some suitable delay, so that in the
// hopefully usual case, we will make the connection to the API
// and never hit the provider. By preference we use provider
// attributes from the config store, but for backward
// compatibility reasons, we fall back to information from
// ReadEnvirons if that does not exist.
chooseError := func(err0, err1 error) error {
if err0 == nil {
return err1
}
if errorImportance(err0) < errorImportance(err1) {
err0, err1 = err1, err0
}
logger.Warningf("discarding API open error: %v", err1)
return err0
}
try := parallel.NewTry(0, chooseError)
info, err := store.ReadInfo(envName)
if err != nil && !errors.IsNotFound(err) {
return nil, err
}
var delay time.Duration
if info != nil && len(info.APIEndpoint().Addresses) > 0 {
logger.Debugf("trying cached API connection settings")
try.Start(func(stop <-chan struct{}) (io.Closer, error) {
return apiInfoConnect(store, info, apiOpen, stop)
})
// Delay the config connection until we've spent
// some time trying to connect to the cached info.
delay = providerConnectDelay
} else {
logger.Debugf("no cached API connection settings found")
}
try.Start(func(stop <-chan struct{}) (io.Closer, error) {
cfg, err := getConfig(info, envs, envName)
if err != nil {
return nil, err
}
return apiConfigConnect(cfg, apiOpen, stop, delay)
})
try.Close()
val0, err := try.Result()
if err != nil {
if ierr, ok := err.(*infoConnectError); ok {
// lose error encapsulation:
err = ierr.error
}
return nil, err
}
st := val0.(apiState)
// Even though we are about to update API addresses based on
// APIHostPorts in cacheChangedAPIAddresses, we first cache the
// addresses based on the provider lookup. This is because older API
// servers didn't return their HostPort information on Login, and we
// still want to cache our connection information to them.
if cachedInfo, ok := st.(apiStateCachedInfo); ok {
st = cachedInfo.apiState
if cachedInfo.cachedInfo != nil && info != nil {
// Cache the connection settings only if we used the
// environment config, but any errors are just logged
// as warnings, because they're not fatal.
err = cacheAPIInfo(info, cachedInfo.cachedInfo)
if err != nil {
logger.Warningf("cannot cache API connection settings: %v", err.Error())
} else {
logger.Infof("updated API connection settings cache")
}
}
}
// Update API addresses if they've changed. Error is non-fatal.
if localerr := cacheChangedAPIAddresses(info, st); localerr != nil {
logger.Warningf("cannot failed to cache API addresses: %v", localerr)
}
return st, nil
}