open-consul/vendor/github.com/hashicorp/raft/peersjson.go

47 lines
1.4 KiB
Go

package raft
import (
"bytes"
"encoding/json"
"io/ioutil"
)
// ReadPeersJSON consumes a legacy peers.json file in the format of the old JSON
// peer store and creates a new-style configuration structure. This can be used
// to migrate this data or perform manual recovery when running protocol versions
// that can interoperate with older, unversioned Raft servers. This should not be
// used once server IDs are in use, because the old peers.json file didn't have
// support for these, nor non-voter suffrage types.
func ReadPeersJSON(path string) (Configuration, error) {
// Read in the file.
buf, err := ioutil.ReadFile(path)
if err != nil {
return Configuration{}, err
}
// Parse it as JSON.
var peers []string
dec := json.NewDecoder(bytes.NewReader(buf))
if err := dec.Decode(&peers); err != nil {
return Configuration{}, err
}
// Map it into the new-style configuration structure. We can only specify
// voter roles here, and the ID has to be the same as the address.
var configuration Configuration
for _, peer := range peers {
server := Server{
Suffrage: Voter,
ID: ServerID(peer),
Address: ServerAddress(peer),
}
configuration.Servers = append(configuration.Servers, server)
}
// We should only ingest valid configurations.
if err := checkConfiguration(configuration); err != nil {
return Configuration{}, err
}
return configuration, nil
}