matthew/packer-plugin-xenserver
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Use buffered reading and higher level APIs to detect when http response is fully parsed

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This commit is contained in:
Dom Del Nano 2021-11-03 07:45:19 -07:00
parent 6e84e6d371
commit 1e4b5dd51b
1 changed files with 30 additions and 28 deletions
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58
builder/xenserver/common/step_type_boot_command.go
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@ -1,8 +1,7 @@
package common
/* Heavily borrowed from builder/quemu/step_type_boot_command.go */
import (
"bufio"
"context"
"crypto/tls"
"fmt"
@ -11,10 +10,10 @@ import (
"net"
"strings"
"github.com/hashicorp/packer-plugin-sdk/bootcommand"
"github.com/hashicorp/packer-plugin-sdk/multistep"
"github.com/hashicorp/packer-plugin-sdk/packer"
"github.com/hashicorp/packer-plugin-sdk/template/interpolate"
"github.com/hashicorp/packer-plugin-sdk/bootcommand"
"github.com/mitchellh/go-vnc"
)
@ -103,36 +102,41 @@ func (self *StepTypeBootCommand) Run(ctx context.Context, state multistep.StateB
return multistep.ActionHalt
}
// Look for \r\n\r\n sequence. Everything after the HTTP Header is for the vnc client.
builder := strings.Builder{}
buffer := make([]byte, 1)
sequenceProgress := 0
// Look for \r\n\r\n sequence. Everything after the HTTP Header is for the vnc client.
reader := bufio.NewReader(tlsConn)
var httpResp string
for {
if _, err := io.ReadFull(tlsConn, buffer); err != nil {
httpResp, err = reader.ReadString('\r')
if err != nil {
err := fmt.Errorf("failed to start vnc session: %v", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
builder.WriteByte(buffer[0])
if buffer[0] == '\n' && sequenceProgress % 2 == 1 {
sequenceProgress++
} else if buffer[0] == '\r' && sequenceProgress % 2 == 0 {
sequenceProgress++
} else {
sequenceProgress = 0
// Peek at the next three bytes to see if it contains the remaining \n\r\n
var b []byte
b, err = reader.Peek(3)
if err != nil {
e := fmt.Errorf("failed to start vnc session: %v", err)
state.Put("error", e)
ui.Error(e.Error())
return multistep.ActionHalt
}
if sequenceProgress == 4 {
if b[0] == '\n' && b[1] == '\r' && b[2] == '\n' {
if _, err = reader.Discard(3); err != nil {
e := fmt.Errorf("failed to start vnc session: %v", err)
state.Put("error", e)
ui.Error(e.Error())
return multistep.ActionHalt
}
break
}
}
ui.Say(fmt.Sprintf("Received response: %s", builder.String()))
ui.Say(fmt.Sprintf("Received response: %s", httpResp))
vncClient, err := vnc.Client(tlsConn, &vnc.ClientConfig{Exclusive: false})
@ -144,7 +148,6 @@ func (self *StepTypeBootCommand) Run(ctx context.Context, state multistep.StateB
}
defer vncClient.Close()
log.Printf("Connected to the VNC console: %s", vncClient.DesktopName)
@ -170,32 +173,31 @@ func (self *StepTypeBootCommand) Run(ctx context.Context, state multistep.StateB
vncDriver := bootcommand.NewVNCDriver(vncClient, config.VNCConfig.BootKeyInterval)
ui.Say("Typing boot commands over VNC...")
command, err := interpolate.Render(config.VNCConfig.FlatBootCommand(), &self.Ctx)
if err != nil {
err := fmt.Errorf("Error preparing boot command: %s", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
seq, err := bootcommand.GenerateExpressionSequence(command)
if err != nil {
err := fmt.Errorf("Error generating boot command: %s", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
if err := seq.Do(ctx, vncDriver); err != nil {
err := fmt.Errorf("Error running boot command: %s", err)
state.Put("error", err)
ui.Error(err.Error())
return multistep.ActionHalt
}
ui.Say("Finished typing.")