// HTTPClientDC returns a new Consul HTTP client with the given address and datacenter
func HTTPClientDC(addr, dc string) (*consulapi.Client, error) {
conf := consulapi.DefaultConfig()
if envAddr := os.Getenv(HTTPAddrEnvName); addr == "" && envAddr != "" {
addr = envAddr
}
conf.Address = addr
conf.Datacenter = dc
return consulapi.NewClient(conf)
}
// Run is used to run a watch plan
func (p *WatchPlan) Run(address string) error {
// Setup the client
p.address = address
conf := consulapi.DefaultConfig()
conf.Address = address
conf.Datacenter = p.Datacenter
conf.Token = p.Token
client, err := consulapi.NewClient(conf)
if err != nil {
return fmt.Errorf("Failed to connect to agent: %v", err)
}
p.client = client
// Create the logger
output := p.LogOutput
if output == nil {
output = os.Stderr
}
logger := log.New(output, "", log.LstdFlags)
// Loop until we are canceled
failures := 0
OUTER:
for !p.shouldStop() {
// Invoke the handler
index, result, err := p.Func(p)
// Check if we should terminate since the function
// could have blocked for a while
if p.shouldStop() {
break
}
// Handle an error in the watch function
if err != nil {
// Perform an exponential backoff
failures++
retry := retryInterval * time.Duration(failures*failures)
if retry > maxBackoffTime {
retry = maxBackoffTime
}
logger.Printf("consul.watch: Watch (type: %s) errored: %v, retry in %v",
p.Type, err, retry)
select {
case <-time.After(retry):
continue OUTER
case <-p.stopCh:
return nil
}
}
// Clear the failures
failures = 0
// If the index is unchanged do nothing
if index == p.lastIndex {
continue
}
// Update the index, look for change
oldIndex := p.lastIndex
p.lastIndex = index
if oldIndex != 0 && reflect.DeepEqual(p.lastResult, result) {
continue
}
// Handle the updated result
p.lastResult = result
if p.Handler != nil {
p.Handler(index, result)
}
}
return nil
}