github.com/ricardclau/terraform@v0.6.17-0.20160519222547-283e3ae6b5a9/help.go (about)

     1  package main
     2  
     3  import (
     4  	"bytes"
     5  	"fmt"
     6  	"log"
     7  	"sort"
     8  	"strings"
     9  
    10  	"github.com/mitchellh/cli"
    11  )
    12  
    13  // helpFunc is a cli.HelpFunc that can is used to output the help for Terraform.
    14  func helpFunc(commands map[string]cli.CommandFactory) string {
    15  	// Determine the maximum key length, and classify based on type
    16  	porcelain := make(map[string]cli.CommandFactory)
    17  	plumbing := make(map[string]cli.CommandFactory)
    18  	maxKeyLen := 0
    19  	for key, f := range commands {
    20  		if len(key) > maxKeyLen {
    21  			maxKeyLen = len(key)
    22  		}
    23  
    24  		if _, ok := PlumbingCommands[key]; ok {
    25  			plumbing[key] = f
    26  		} else {
    27  			porcelain[key] = f
    28  		}
    29  	}
    30  
    31  	var buf bytes.Buffer
    32  	buf.WriteString("usage: terraform [--version] [--help] <command> [args]\n\n")
    33  	buf.WriteString(
    34  		"The available commands for execution are listed below.\n" +
    35  			"The most common, useful commands are shown first, followed by\n" +
    36  			"less common or more advanced commands. If you're just getting\n" +
    37  			"started with Terraform, stick with the common commands. For the\n" +
    38  			"other commands, please read the help and docs before usage.\n\n")
    39  	buf.WriteString("Common commands:\n")
    40  	buf.WriteString(listCommands(porcelain, maxKeyLen))
    41  	buf.WriteString("\nAll other commands:\n")
    42  	buf.WriteString(listCommands(plumbing, maxKeyLen))
    43  	return buf.String()
    44  }
    45  
    46  // listCommands just lists the commands in the map with the
    47  // given maximum key length.
    48  func listCommands(commands map[string]cli.CommandFactory, maxKeyLen int) string {
    49  	var buf bytes.Buffer
    50  
    51  	// Get the list of keys so we can sort them, and also get the maximum
    52  	// key length so they can be aligned properly.
    53  	keys := make([]string, 0, len(commands))
    54  	for key, _ := range commands {
    55  		// This is an internal command that users should never call directly so
    56  		// we will hide it from the command listing.
    57  		if key == "internal-plugin" {
    58  			continue
    59  		}
    60  		keys = append(keys, key)
    61  	}
    62  	sort.Strings(keys)
    63  
    64  	for _, key := range keys {
    65  		commandFunc, ok := commands[key]
    66  		if !ok {
    67  			// This should never happen since we JUST built the list of
    68  			// keys.
    69  			panic("command not found: " + key)
    70  		}
    71  
    72  		command, err := commandFunc()
    73  		if err != nil {
    74  			log.Printf("[ERR] cli: Command '%s' failed to load: %s",
    75  				key, err)
    76  			continue
    77  		}
    78  
    79  		key = fmt.Sprintf("%s%s", key, strings.Repeat(" ", maxKeyLen-len(key)))
    80  		buf.WriteString(fmt.Sprintf("    %s    %s\n", key, command.Synopsis()))
    81  	}
    82  
    83  	return buf.String()
    84  }