/
machine.go
70 lines (62 loc) · 1.8 KB
/
machine.go
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/*
* Tencent is pleased to support the open source community by making TKEStack
* available.
*
* Copyright (C) 2012-2019 Tencent. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the “License”); you may not use
* this file except in compliance with the License. You may obtain a copy of the
* License at
*
* https://opensource.org/licenses/Apache-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an “AS IS” BASIS, WITHOUT
* WARRANTIES OF ANY KIND, either express or implied. See the License for the
* specific language governing permissions and limitations under the License.
*/
package machine
import (
"fmt"
"sort"
"sync"
)
var (
providersMu sync.RWMutex
providers = make(map[string]Provider)
)
// Register makes a provider available by the provided name.
// If Register is called twice with the same name or if provider is nil,
// it panics.
func Register(name string, provider Provider) {
providersMu.Lock()
defer providersMu.Unlock()
if provider == nil {
panic("machine: Register provider is nil")
}
if _, dup := providers[name]; dup {
panic("machine: Register called twice for provider " + name)
}
providers[name] = provider
}
// Providers returns a sorted list of the names of the registered providers.
func Providers() []string {
providersMu.RLock()
defer providersMu.RUnlock()
var list []string
for name := range providers {
list = append(list, name)
}
sort.Strings(list)
return list
}
// GetProvider returns provider by name
func GetProvider(name string) (Provider, error) {
providersMu.RLock()
provider, ok := providers[name]
providersMu.RUnlock()
if !ok {
return nil, fmt.Errorf("machine: unknown provider %q (forgotten import?)", name)
}
return provider, nil
}