terraform/command/plan.go

package command

import (
	"fmt"
	"strings"

	"github.com/hashicorp/terraform/backend"
	"github.com/hashicorp/terraform/command/arguments"
	"github.com/hashicorp/terraform/command/views"
	"github.com/hashicorp/terraform/configs"
	"github.com/hashicorp/terraform/terraform"
	"github.com/hashicorp/terraform/tfdiags"
)

// PlanCommand is a Command implementation that compares a Terraform
// configuration to an actual infrastructure and shows the differences.
type PlanCommand struct {
	Meta
}

func (c *PlanCommand) Run(args []string) int {
	var destroy, refresh, detailed bool
	var outPath string

	args = c.Meta.process(args)
	cmdFlags := c.Meta.extendedFlagSet("plan")
	cmdFlags.BoolVar(&destroy, "destroy", false, "destroy")
	cmdFlags.BoolVar(&refresh, "refresh", true, "refresh")
	cmdFlags.StringVar(&outPath, "out", "", "path")
	cmdFlags.IntVar(&c.Meta.parallelism, "parallelism", DefaultParallelism, "parallelism")
	cmdFlags.StringVar(&c.Meta.statePath, "state", "", "path")
	cmdFlags.BoolVar(&detailed, "detailed-exitcode", false, "detailed-exitcode")
	cmdFlags.BoolVar(&c.Meta.stateLock, "lock", true, "lock state")
	cmdFlags.DurationVar(&c.Meta.stateLockTimeout, "lock-timeout", 0, "lock timeout")
	cmdFlags.Usage = func() { c.Ui.Error(c.Help()) }
	if err := cmdFlags.Parse(args); err != nil {
		c.Ui.Error(fmt.Sprintf("Error parsing command-line flags: %s\n", err.Error()))
		return 1
	}

	diags := c.parseTargetFlags()
	if diags.HasErrors() {
		c.showDiagnostics(diags)
		return 1
	}

	configPath, err := ModulePath(cmdFlags.Args())
	if err != nil {
		c.Ui.Error(err.Error())
		return 1
	}

	// Check for user-supplied plugin path
	if c.pluginPath, err = c.loadPluginPath(); err != nil {
		c.Ui.Error(fmt.Sprintf("Error loading plugin path: %s", err))
		return 1
	}

	var backendConfig *configs.Backend
	var configDiags tfdiags.Diagnostics
	backendConfig, configDiags = c.loadBackendConfig(configPath)
	diags = diags.Append(configDiags)
	if configDiags.HasErrors() {
		c.showDiagnostics(diags)
		return 1
	}

	// Load the backend
	b, backendDiags := c.Backend(&BackendOpts{
		Config: backendConfig,
	})
	diags = diags.Append(backendDiags)
	if backendDiags.HasErrors() {
		c.showDiagnostics(diags)
		return 1
	}

	// Emit any diagnostics we've accumulated before we delegate to the
	// backend, since the backend will handle its own diagnostics internally.
	c.showDiagnostics(diags)
	diags = nil

	// Build the operation
	opReq := c.Operation(b)
	opReq.ConfigDir = configPath
	opReq.Destroy = destroy
	opReq.Hooks = []terraform.Hook{c.uiHook()}
	opReq.PlanOutPath = outPath
	opReq.PlanRefresh = refresh
	opReq.ShowDiagnostics = c.showDiagnostics
	opReq.Type = backend.OperationTypePlan
	opReq.View = views.NewOperation(arguments.ViewHuman, c.RunningInAutomation, c.View)

	opReq.ConfigLoader, err = c.initConfigLoader()
	if err != nil {
		c.showDiagnostics(err)
		return 1
	}

	{
		var moreDiags tfdiags.Diagnostics
		opReq.Variables, moreDiags = c.collectVariableValues()
		diags = diags.Append(moreDiags)
		if moreDiags.HasErrors() {
			c.showDiagnostics(diags)
			return 1
		}
	}

	// Perform the operation
	op, err := c.RunOperation(b, opReq)
	if err != nil {
		c.showDiagnostics(err)
		return 1
	}

	if op.Result != backend.OperationSuccess {
		return op.Result.ExitStatus()
	}
	if detailed && !op.PlanEmpty {
		return 2
	}

	return op.Result.ExitStatus()
}

func (c *PlanCommand) Help() string {
	helpText := `
Usage: terraform plan [options]

  Generates a speculative execution plan, showing what actions Terraform
  would take to apply the current configuration. This command will not
  actually perform the planned actions.

  You can optionally save the plan to a file, which you can then pass to
  the "apply" command to perform exactly the actions described in the plan.

Options:

  -compact-warnings   If Terraform produces any warnings that are not
                      accompanied by errors, show them in a more compact form
                      that includes only the summary messages.

  -destroy            If set, a plan will be generated to destroy all resources
                      managed by the given configuration and state.

  -detailed-exitcode  Return detailed exit codes when the command exits. This
                      will change the meaning of exit codes to:
                      0 - Succeeded, diff is empty (no changes)
                      1 - Errored
                      2 - Succeeded, there is a diff

  -input=true         Ask for input for variables if not directly set.

  -lock=true          Lock the state file when locking is supported.

  -lock-timeout=0s    Duration to retry a state lock.

  -no-color           If specified, output won't contain any color.

  -out=path           Write a plan file to the given path. This can be used as
                      input to the "apply" command.

  -parallelism=n      Limit the number of concurrent operations. Defaults to 10.

  -refresh=true       Update state prior to checking for differences.

  -state=statefile    Path to a Terraform state file to use to look
                      up Terraform-managed resources. By default it will
                      use the state "terraform.tfstate" if it exists.

  -target=resource    Resource to target. Operation will be limited to this
                      resource and its dependencies. This flag can be used
                      multiple times.

  -var 'foo=bar'      Set a variable in the Terraform configuration. This
                      flag can be set multiple times.

  -var-file=foo       Set variables in the Terraform configuration from
                      a file. If "terraform.tfvars" or any ".auto.tfvars"
                      files are present, they will be automatically loaded.
`
	return strings.TrimSpace(helpText)
}

func (c *PlanCommand) Synopsis() string {
	return "Show changes required by the current configuration"
}