// SetBootstrapTools returns the newest tools from the given tools list,
// and updates the agent-version configuration attribute.
func SetBootstrapTools(environ environs.Environ, possibleTools coretools.List) (coretools.List, error) {
if len(possibleTools) == 0 {
return nil, fmt.Errorf("no bootstrap tools available")
}
var newVersion version.Number
newVersion, toolsList := possibleTools.Newest()
logger.Infof("newest version: %s", newVersion)
cfg := environ.Config()
if agentVersion, _ := cfg.AgentVersion(); agentVersion != newVersion {
cfg, err := cfg.Apply(map[string]interface{}{
"agent-version": newVersion.String(),
})
if err == nil {
err = environ.SetConfig(cfg)
}
if err != nil {
return nil, fmt.Errorf("failed to update environment configuration: %v", err)
}
}
bootstrapVersion := newVersion
// We should only ever bootstrap the exact same version as the client,
// or we risk bootstrap incompatibility. We still set agent-version to
// the newest version, so the agent will immediately upgrade itself.
if !isCompatibleVersion(newVersion, version.Current.Number) {
compatibleVersion, compatibleTools := findCompatibleTools(possibleTools, version.Current.Number)
if len(compatibleTools) == 0 {
logger.Warningf(
"failed to find %s tools, will attempt to use %s",
version.Current.Number, newVersion,
)
} else {
bootstrapVersion, toolsList = compatibleVersion, compatibleTools
}
}
logger.Infof("picked bootstrap tools version: %s", bootstrapVersion)
return toolsList, nil
}
// SetEnvironAgentVersion changes the agent version for the
// environment to the given version, only if the environment is in a
// stable state (all agents are running the current version).
func (st *State) SetEnvironAgentVersion(newVersion version.Number) error {
for i := 0; i < 5; i++ {
settings, err := readSettings(st, environGlobalKey)
if err != nil {
return err
}
agentVersion, ok := settings.Get("agent-version")
if !ok {
return fmt.Errorf("no agent version set in the environment")
}
currentVersion, ok := agentVersion.(string)
if !ok {
return fmt.Errorf("invalid agent version format: expected string, got %v", agentVersion)
}
if newVersion.String() == currentVersion {
// Nothing to do.
return nil
}
if err := st.checkCanUpgrade(currentVersion, newVersion.String()); err != nil {
return err
}
ops := []txn.Op{{
C: st.settings.Name,
Id: environGlobalKey,
Assert: bson.D{{"txn-revno", settings.txnRevno}},
Update: bson.D{{"$set", bson.D{{"agent-version", newVersion.String()}}}},
}}
if err := st.runTransaction(ops); err == nil {
return nil
} else if err != txn.ErrAborted {
return fmt.Errorf("cannot set agent-version: %v", err)
}
}
return ErrExcessiveContention
}
// SetAgentVersion sets the current agent version in the state's
// environment configuration.
// This is similar to state.SetEnvironAgentVersion but it doesn't require that
// the environment have all agents at the same version already.
func SetAgentVersion(st *state.State, vers version.Number) error {
return st.UpdateEnvironConfig(map[string]interface{}{"agent-version": vers.String()}, nil, nil)
}