34 lines
718 B
Go
34 lines
718 B
Go
package stone
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import "time"
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import "errors"
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type Backend interface {
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Run () (chan(Event))
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SetTitle (title string)
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}
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type BackendFactory func (application *Application) (backend Backend, err error)
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var factories []BackendFactory
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func RegisterBackend (factory BackendFactory) {
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factories = append(factories, factory)
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}
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func instantiateBackend (application *Application) (backend Backend, err error) {
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// find a suitable backend
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for _, factory := range factories {
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backend, err = factory(application)
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if err == nil && backend != nil { return }
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}
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// if none were found, but there was no error produced, produce an
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// error
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if err == nil {
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err = errors.New("no available backends")
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}
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return
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}
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