open-nomad/client/driver/utils.go

112 lines
3.1 KiB
Go

package driver
import (
"fmt"
"io"
"os"
"strings"
"github.com/hashicorp/go-multierror"
"github.com/hashicorp/go-plugin"
"github.com/hashicorp/nomad/client/config"
"github.com/hashicorp/nomad/client/driver/executor"
"github.com/hashicorp/nomad/client/driver/logging"
)
// createExecutor launches an executor plugin and returns an instance of the
// Executor interface
func createExecutor(config *plugin.ClientConfig, w io.Writer,
clientConfig *config.Config) (executor.Executor, *plugin.Client, error) {
config.HandshakeConfig = HandshakeConfig
config.Plugins = GetPluginMap(w)
config.MaxPort = clientConfig.ClientMaxPort
config.MinPort = clientConfig.ClientMinPort
// setting the setsid of the plugin process so that it doesn't get signals sent to
// the nomad client.
if config.Cmd != nil {
isolateCommand(config.Cmd)
}
executorClient := plugin.NewClient(config)
rpcClient, err := executorClient.Client()
if err != nil {
return nil, nil, fmt.Errorf("error creating rpc client for executor plugin: %v", err)
}
raw, err := rpcClient.Dispense("executor")
if err != nil {
return nil, nil, fmt.Errorf("unable to dispense the executor plugin: %v", err)
}
executorPlugin := raw.(executor.Executor)
return executorPlugin, executorClient, nil
}
func createLogCollector(config *plugin.ClientConfig, w io.Writer,
clientConfig *config.Config) (logging.LogCollector, *plugin.Client, error) {
config.HandshakeConfig = HandshakeConfig
config.Plugins = GetPluginMap(w)
config.MaxPort = clientConfig.ClientMaxPort
config.MinPort = clientConfig.ClientMinPort
if config.Cmd != nil {
isolateCommand(config.Cmd)
}
syslogClient := plugin.NewClient(config)
rpcCLient, err := syslogClient.Client()
if err != nil {
return nil, nil, fmt.Errorf("error creating rpc client for syslog plugin: %v", err)
}
raw, err := rpcCLient.Dispense("syslogcollector")
if err != nil {
return nil, nil, fmt.Errorf("unable to dispense the syslog plugin: %v", err)
}
logCollector := raw.(logging.LogCollector)
return logCollector, syslogClient, nil
}
// killProcess kills a process with the given pid
func killProcess(pid int) error {
proc, err := os.FindProcess(pid)
if err != nil {
return err
}
return proc.Kill()
}
// destroyPlugin kills the plugin with the given pid and also kills the user
// process
func destroyPlugin(pluginPid int, userPid int) error {
var merr error
if err := killProcess(pluginPid); err != nil {
merr = multierror.Append(merr, err)
}
if err := killProcess(userPid); err != nil {
merr = multierror.Append(merr, err)
}
return merr
}
// validateCommand validates that the command only has a single value and
// returns a user friendly error message telling them to use the passed
// argField.
func validateCommand(command, argField string) error {
trimmed := strings.TrimSpace(command)
if len(trimmed) == 0 {
return fmt.Errorf("command empty: %q", command)
}
if len(trimmed) != len(command) {
return fmt.Errorf("command contains extra white space: %q", command)
}
split := strings.Split(trimmed, " ")
if len(split) != 1 {
return fmt.Errorf("command contained more than one input. Use %q field to pass arguments", argField)
}
return nil
}