packer-cn/packer/rpc/provisioner.go

91 lines
2.2 KiB
Go

package rpc
import (
"context"
"log"
"net/rpc"
"github.com/hashicorp/packer/packer"
)
// An implementation of packer.Provisioner where the provisioner is actually
// executed over an RPC connection.
type provisioner struct {
client *rpc.Client
mux *muxBroker
}
// ProvisionerServer wraps a packer.Provisioner implementation and makes it
// exportable as part of a Golang RPC server.
type ProvisionerServer struct {
context context.Context
contextCancel func()
p packer.Provisioner
mux *muxBroker
}
type ProvisionerPrepareArgs struct {
Configs []interface{}
}
func (p *provisioner) Prepare(configs ...interface{}) (err error) {
args := &ProvisionerPrepareArgs{configs}
if cerr := p.client.Call("Provisioner.Prepare", args, new(interface{})); cerr != nil {
err = cerr
}
return
}
func (p *provisioner) Provision(ctx context.Context, ui packer.Ui, comm packer.Communicator, generatedData *packer.ProvisionHookData) error {
nextId := p.mux.NextId()
server := newServerWithMux(p.mux, nextId)
server.RegisterCommunicator(comm)
server.RegisterUi(ui)
go server.Serve()
done := make(chan interface{})
defer close(done)
go func() {
select {
case <-ctx.Done():
log.Printf("Cancelling provisioner after context cancellation %v", ctx.Err())
if err := p.client.Call("Provisioner.Cancel", new(interface{}), new(interface{})); err != nil {
log.Printf("Error cancelling provisioner: %s", err)
}
case <-done:
}
}()
return p.client.Call("Provisioner.Provision", nextId, new(interface{}))
}
func (p *ProvisionerServer) Prepare(args *ProvisionerPrepareArgs, reply *interface{}) error {
return p.p.Prepare(args.Configs...)
}
func (p *ProvisionerServer) Provision(streamId uint32, reply *interface{}, generatedData *packer.ProvisionHookData) error {
client, err := newClientWithMux(p.mux, streamId)
if err != nil {
return NewBasicError(err)
}
defer client.Close()
if p.context == nil {
p.context, p.contextCancel = context.WithCancel(context.Background())
}
if err := p.p.Provision(p.context, client.Ui(), client.Communicator(), generatedData); err != nil {
return NewBasicError(err)
}
return nil
}
func (p *ProvisionerServer) Cancel(args *interface{}, reply *interface{}) error {
p.contextCancel()
return nil
}