pkg/module/module.go

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// the Apache License, Version 2.0 (the "License"); you may
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//
//     http://www.apache.org/licenses/LICENSE-2.0
//
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// under the License.

package module

import "context"

// Module define
type Module interface {
	// Name of module.
	// It would be use when declaring this module into configuration or other module need to reference.
	Name() string

	// RequiredModules means which modules do this module is depended on,
	// The current module started after the dependent modules are Start success.
	RequiredModules() []string

	// Config of this module
	// The config is automatically read from the configuration file before module Start
	Config() ConfigInterface

	// Start module
	// The module needs to return the start result after startup is completed
	Start(ctx context.Context, mgr *Manager) error

	// NotifyStartSuccess when all module have been start success
	NotifyStartSuccess()

	// Shutdown module, the sequence of shutdown is the reverse of the module Start
	// The shutdown would trigger in the following cases
	// 1. If other modules fail to start
	// 2. The module is actively shutdown through Manager.ShutdownModules
	// 3. The Rover receive the close SIGNAL
	Shutdown(ctx context.Context, mgr *Manager) error
}