40 lines
1.0 KiB
Go
40 lines
1.0 KiB
Go
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package amazonebs
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// A StepAction determines the next step to take regarding multi-step actions.
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type StepAction uint
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const (
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StepContinue StepAction = iota
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StepHalt
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)
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// Step is a single step that is part of a potentially large sequence
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// of other steps, responsible for performing some specific action.
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type Step interface {
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// Run is called to perform the action. The parameter is a "state bag"
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// of untyped things. Please be very careful about type-checking the
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// items in this bag.
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//
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// The return value determines whether multi-step sequences continue
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// or should halt.
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Run(map[string]interface{}) StepAction
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// Cleanup is called in reverse order of the steps that have run
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// and allow steps to clean up after themselves.
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//
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// The parameter is the same "state bag" as Run.
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Cleanup(map[string]interface{})
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}
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// RunSteps runs a sequence of steps.
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func RunSteps(state map[string]interface{}, steps []Step) {
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for _, step := range steps {
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action := step.Run(state)
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defer step.Cleanup(state)
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if action == StepHalt {
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break
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}
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}
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}
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