Documentation
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Index ¶
Constants ¶
This section is empty.
Variables ¶
var ErrWaitAborted = errors.New("environ wait aborted")
ErrWaitAborted is returned from WaitForEnviron when the wait is terminated by closing the abort chan.
Functions ¶
func Manifold ¶
func Manifold(config ManifoldConfig) dependency.Manifold
Manifold returns a Manifold that encapsulates a *Tracker and exposes it as an environs.Environ resource.
func WaitForEnviron ¶
func WaitForEnviron( w watcher.NotifyWatcher, getter ConfigGetter, newEnviron NewEnvironFunc, abort <-chan struct{}, ) (environs.Environ, error)
WaitForEnviron waits for an valid environment to arrive from the given watcher. It terminates with ErrWaitAborted if it receives a value on abort.
In practice, it shouldn't wait at all: juju *should* never deliver invalid environ configs. Regardless, it should be considered deprecated; clients should prefer to access an Environ via a shared Tracker.
It never takes responsibility for the supplied watcher; the client remains responsible for detecting and handling any watcher errors that may occur, whether this func succeeds or fails.
Types ¶
type Config ¶
type Config struct {
Observer ConfigObserver
NewEnvironFunc NewEnvironFunc
}
Config describes the dependencies of a Tracker.
It's arguable that it should be called TrackerConfig, because of the heavy use of model config in this package.
type ConfigGetter ¶
ConfigGetter exposes a model configuration to its clients.
type ConfigObserver ¶
type ConfigObserver interface {
ConfigGetter
WatchForModelConfigChanges() (watcher.NotifyWatcher, error)
}
ConfigObserver exposes a model configuration and a watch constructor that allows clients to be informed of changes to the configuration.
type ManifoldConfig ¶
type ManifoldConfig struct {
APICallerName string
NewEnvironFunc NewEnvironFunc
}
ManifoldConfig describes the resources used by a Tracker.
type NewEnvironFunc ¶
NewEnvironFunc is the type of a function that, given a model config, returns an Environ. This will typically be environs.New.
type Tracker ¶
type Tracker struct {
// contains filtered or unexported fields
}
Tracker loads an environment, makes it available to clients, and updates the environment in response to config changes until it is killed.
func NewTracker ¶
NewTracker loads an environment from the observer and returns a new Tracker, or an error if anything goes wrong. If a tracker is returned, its Environ() method is immediately usable.
The caller is responsible for Kill()ing the returned Tracker and Wait()ing for any errors it might return.
Source Files