57 lines
1.3 KiB
Go
57 lines
1.3 KiB
Go
package cluster
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import (
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"encoding/json"
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"io/ioutil"
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"os"
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"path/filepath"
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"github.com/docker/docker/pkg/ioutils"
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)
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func loadPersistentState(root string) (*nodeStartConfig, error) {
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dt, err := ioutil.ReadFile(filepath.Join(root, stateFile))
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if err != nil {
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return nil, err
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}
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// missing certificate means no actual state to restore from
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if _, err := os.Stat(filepath.Join(root, "certificates/swarm-node.crt")); err != nil {
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if os.IsNotExist(err) {
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clearPersistentState(root)
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}
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return nil, err
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}
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var st nodeStartConfig
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if err := json.Unmarshal(dt, &st); err != nil {
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return nil, err
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}
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return &st, nil
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}
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func savePersistentState(root string, config nodeStartConfig) error {
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dt, err := json.Marshal(config)
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if err != nil {
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return err
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}
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return ioutils.AtomicWriteFile(filepath.Join(root, stateFile), dt, 0600)
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}
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func clearPersistentState(root string) error {
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// todo: backup this data instead of removing?
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if err := os.RemoveAll(root); err != nil {
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return err
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}
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if err := os.MkdirAll(root, 0700); err != nil {
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return err
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}
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return nil
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}
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func removingManagerCausesLossOfQuorum(reachable, unreachable int) bool {
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return reachable-2 <= unreachable
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}
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func isLastManager(reachable, unreachable int) bool {
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return reachable == 1 && unreachable == 0
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}
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