package command import ( "flag" "fmt" "os" "strings" "github.com/hashicorp/terraform/terraform" ) // OutputCommand is a Command implementation that reads an output // from a Terraform state and prints it. type OutputCommand struct { Meta } func (c *OutputCommand) Run(args []string) int { var statePath string args = c.Meta.process(args, false) cmdFlags := flag.NewFlagSet("output", flag.ContinueOnError) cmdFlags.StringVar(&statePath, "state", DefaultStateFilename, "path") cmdFlags.Usage = func() { c.Ui.Error(c.Help()) } if err := cmdFlags.Parse(args); err != nil { return 1 } args = cmdFlags.Args() if len(args) != 1 || args[0] == "" { c.Ui.Error( "The output command expects exactly one argument with the name\n" + "of an output variable.\n") cmdFlags.Usage() return 1 } name := args[0] f, err := os.Open(statePath) if err != nil { c.Ui.Error(fmt.Sprintf("Error loading file: %s", err)) return 1 } state, err := terraform.ReadState(f) f.Close() if err != nil { c.Ui.Error(fmt.Sprintf("Error reading state: %s", err)) return 1 } if len(state.Outputs) == 0 { c.Ui.Error(fmt.Sprintf( "The state file has no outputs defined. Define an output\n" + "in your configuration with the `output` directive and re-run\n" + "`terraform apply` for it to become available.")) return 1 } v, ok := state.Outputs[name] if !ok { c.Ui.Error(fmt.Sprintf( "The output variable requested could not be found in the state\n" + "file. If you recently added this to your configuration, be\n" + "sure to run `terraform apply`, since the state won't be updated\n" + "with new output variables until that command is run.")) return 1 } c.Ui.Output(v) return 0 } func (c *OutputCommand) Help() string { helpText := ` Usage: terraform output [options] NAME Reads an output variable from a Terraform state file and prints the value. Options: -state=path Path to the state file to read. Defaults to "terraform.tfstate". ` return strings.TrimSpace(helpText) } func (c *OutputCommand) Synopsis() string { return "Read an output from a state file" }