github.com/altoros/juju-vmware@v0.0.0-20150312064031-f19ae857ccca/cmd/juju/destroyenvironment.go

// Copyright 2012, 2013 Canonical Ltd.
// Licensed under the AGPLv3, see LICENCE file for details.

package main

import (
	"bufio"
	stderrors "errors"
	"fmt"
	"io"
	"strings"

	"github.com/juju/cmd"
	"github.com/juju/errors"
	"launchpad.net/gnuflag"

	"github.com/juju/juju/apiserver/params"
	"github.com/juju/juju/cmd/envcmd"
	"github.com/juju/juju/cmd/juju/block"
	"github.com/juju/juju/environs"
	"github.com/juju/juju/environs/configstore"
	"github.com/juju/juju/juju"
)

var NoEnvironmentError = stderrors.New("no environment specified")
var DoubleEnvironmentError = stderrors.New("you cannot supply both -e and the envname as a positional argument")

// DestroyEnvironmentCommand destroys an environment.
type DestroyEnvironmentCommand struct {
	envcmd.EnvCommandBase
	cmd.CommandBase
	envName   string
	assumeYes bool
	force     bool
}

func (c *DestroyEnvironmentCommand) Info() *cmd.Info {
	return &cmd.Info{
		Name:    "destroy-environment",
		Args:    "<environment name>",
		Purpose: "terminate all machines and other associated resources for an environment",
	}
}

func (c *DestroyEnvironmentCommand) SetFlags(f *gnuflag.FlagSet) {
	f.BoolVar(&c.assumeYes, "y", false, "Do not ask for confirmation")
	f.BoolVar(&c.assumeYes, "yes", false, "")
	f.BoolVar(&c.force, "force", false, "Forcefully destroy the environment, directly through the environment provider")
	f.StringVar(&c.envName, "e", "", "juju environment to operate in")
	f.StringVar(&c.envName, "environment", "", "juju environment to operate in")
}

func (c *DestroyEnvironmentCommand) Init(args []string) error {
	if c.envName != "" {
		logger.Warningf("-e/--environment flag is deprecated in 1.18, " +
			"please supply environment as a positional parameter")
		// They supplied the -e flag
		if len(args) == 0 {
			// We're happy, we have enough information
			return nil
		}
		// You can't supply -e ENV and ENV as a positional argument
		return DoubleEnvironmentError
	}
	// No -e flag means they must supply the environment positionally
	switch len(args) {
	case 0:
		return NoEnvironmentError
	case 1:
		c.envName = args[0]
		return nil
	default:
		return cmd.CheckEmpty(args[1:])
	}
}

func (c *DestroyEnvironmentCommand) Run(ctx *cmd.Context) (result error) {
	store, err := configstore.Default()
	if err != nil {
		return fmt.Errorf("cannot open environment info storage: %v", err)
	}
	environ, err := environs.NewFromName(c.envName, store)
	if err != nil {
		if environs.IsEmptyConfig(err) {
			// Delete the .jenv file and call it done.
			ctx.Infof("removing empty environment file")
			return environs.DestroyInfo(c.envName, store)
		}
		return err
	}
	if !c.assumeYes {
		fmt.Fprintf(ctx.Stdout, destroyEnvMsg, c.envName, environ.Config().Type())

		scanner := bufio.NewScanner(ctx.Stdin)
		scanner.Scan()
		err := scanner.Err()
		if err != nil && err != io.EOF {
			return fmt.Errorf("Environment destruction aborted: %s", err)
		}
		answer := strings.ToLower(scanner.Text())
		if answer != "y" && answer != "yes" {
			return stderrors.New("environment destruction aborted")
		}
	}
	// If --force is supplied, then don't attempt to use the API.
	// This is necessary to destroy broken environments, where the
	// API server is inaccessible or faulty.
	if !c.force {
		defer func() {
			result = c.ensureUserFriendlyErrorLog(result)
		}()
		apiclient, err := juju.NewAPIClientFromName(c.envName)
		if err != nil {
			return errors.Annotate(err, "cannot connect to API")
		}
		defer apiclient.Close()
		err = apiclient.DestroyEnvironment()
		if cmdErr := processDestroyError(err); cmdErr != nil {
			return cmdErr
		}
	}
	return environs.Destroy(environ, store)
}

// processDestroyError determines how to format error message based on its code.
// Note that CodeNotImplemented errors have not be propogated in previous implementation.
// This behaviour was preserved.
func processDestroyError(err error) error {
	if err == nil || params.IsCodeNotImplemented(err) {
		return nil
	}
	if params.IsCodeOperationBlocked(err) {
		return err
	}
	return errors.Annotate(err, "destroying environment")
}

// ensureUserFriendlyErrorLog ensures that error will be logged and displayed
// in a user-friendly manner with readable and digestable error message.
func (c *DestroyEnvironmentCommand) ensureUserFriendlyErrorLog(err error) error {
	if err == nil {
		return nil
	}
	if params.IsCodeOperationBlocked(err) {
		return block.ProcessBlockedError(err, block.BlockDestroy)
	}
	logger.Errorf(stdFailureMsg, c.envName)
	return err
}

var destroyEnvMsg = `
WARNING! this command will destroy the %q environment (type: %s)
This includes all machines, services, data and other resources.

Continue [y/N]? `[1:]

var stdFailureMsg = `failed to destroy environment %q

If the environment is unusable, then you may run

    juju destroy-environment --force

to forcefully destroy the environment. Upon doing so, review
your environment provider console for any resources that need
to be cleaned up. Using force will also by-pass destroy-envrionment block.

`