mirror of https://github.com/status-im/consul.git
85 lines
2.1 KiB
Go
85 lines
2.1 KiB
Go
package watch
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import (
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"fmt"
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"github.com/armon/consul-api"
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)
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// watchFactory is a function that can create a new WatchFunc
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// from a parameter configuration
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type watchFactory func(params map[string][]string) (WatchFunc, error)
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// watchFuncFactory maps each type to a factory function
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var watchFuncFactory map[string]watchFactory
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func init() {
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watchFuncFactory = map[string]watchFactory{
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"key": keyWatch,
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"keyprefix": keyPrefixWatch,
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"services": servicesWatch,
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"nodes": nil,
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"service": nil,
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"checks": nil,
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}
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}
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// keyWatch is used to return a key watching function
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func keyWatch(params map[string][]string) (WatchFunc, error) {
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keys := params["key"]
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delete(params, "key")
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if len(keys) != 1 {
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return nil, fmt.Errorf("Must specify a single key to watch")
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}
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key := keys[0]
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fn := func(p *WatchPlan) (uint64, interface{}, error) {
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kv := p.client.KV()
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opts := consulapi.QueryOptions{WaitIndex: p.lastIndex}
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pair, meta, err := kv.Get(key, &opts)
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if err != nil {
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return 0, nil, err
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}
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if pair == nil {
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return meta.LastIndex, nil, err
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}
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return meta.LastIndex, pair, err
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}
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return fn, nil
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}
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// keyPrefixWatch is used to return a key prefix watching function
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func keyPrefixWatch(params map[string][]string) (WatchFunc, error) {
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list := params["prefix"]
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delete(params, "prefix")
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if len(list) != 1 {
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return nil, fmt.Errorf("Must specify a single prefix to watch")
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}
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prefix := list[0]
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fn := func(p *WatchPlan) (uint64, interface{}, error) {
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kv := p.client.KV()
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opts := consulapi.QueryOptions{WaitIndex: p.lastIndex}
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pairs, meta, err := kv.List(prefix, &opts)
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if err != nil {
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return 0, nil, err
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}
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return meta.LastIndex, pairs, err
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}
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return fn, nil
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}
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// servicesWatch is used to watch the list of available services
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func servicesWatch(params map[string][]string) (WatchFunc, error) {
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fn := func(p *WatchPlan) (uint64, interface{}, error) {
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catalog := p.client.Catalog()
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opts := consulapi.QueryOptions{WaitIndex: p.lastIndex}
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services, meta, err := catalog.Services(&opts)
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if err != nil {
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return 0, nil, err
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}
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return meta.LastIndex, services, err
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}
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return fn, nil
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}
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