youtubebeat/vendor/github.com/elastic/beats/libbeat/autodiscover/provider.go

84 lines
2.4 KiB
Go

// Licensed to Elasticsearch B.V. under one or more contributor
// license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright
// ownership. Elasticsearch B.V. licenses this file to you 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
//
// http://www.apache.org/licenses/LICENSE-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 OR CONDITIONS OF ANY
// KIND, either express or implied. See the License for the
// specific language governing permissions and limitations
// under the License.
package autodiscover
import (
"fmt"
"strings"
"github.com/elastic/beats/libbeat/cfgfile"
"github.com/elastic/beats/libbeat/common"
"github.com/elastic/beats/libbeat/common/bus"
"github.com/elastic/beats/libbeat/logp"
)
// Provider for autodiscover
type Provider interface {
cfgfile.Runner
}
// ProviderBuilder creates a new provider based on the given config and returns it
type ProviderBuilder func(bus.Bus, *common.Config) (Provider, error)
// AddProvider registers a new ProviderBuilder
func (r *registry) AddProvider(name string, provider ProviderBuilder) error {
r.lock.Lock()
defer r.lock.Unlock()
if name == "" {
return fmt.Errorf("provider name is required")
}
_, exists := r.providers[name]
if exists {
return fmt.Errorf("provider '%s' is already registered", name)
}
if provider == nil {
return fmt.Errorf("provider '%s' cannot be registered with a nil factory", name)
}
r.providers[name] = provider
logp.Debug(debugK, "Provider registered: %s", name)
return nil
}
// GetProvider returns the provider with the giving name, nil if it doesn't exist
func (r *registry) GetProvider(name string) ProviderBuilder {
r.lock.RLock()
defer r.lock.RUnlock()
name = strings.ToLower(name)
return r.providers[name]
}
// BuildProvider reads provider configuration and instantiate one
func (r *registry) BuildProvider(bus bus.Bus, c *common.Config) (Provider, error) {
var config ProviderConfig
err := c.Unpack(&config)
if err != nil {
return nil, err
}
builder := r.GetProvider(config.Type)
if builder == nil {
return nil, fmt.Errorf("Unknown autodiscover provider %s", config.Type)
}
return builder(bus, c)
}