aliases.go

package main

import (
	"fmt"
	"gopkg.in/yaml.v2"
	"html/template"
	"io"
	"io/ioutil"
	"regexp"
	"sort"
	"strings"
)

type aliasConfig struct {
	AllArgs               string            `yaml:"allArgs"`
	AllExecs              map[string]string `yaml:"allExecs"`
	DefaultAdditionalArgs string            `yaml:"defaultAdditionalArgs"`
	Teams                 []team            `yaml:"teams"`
}

type team struct {
	Name           string    `yaml:"name"`
	AdditionalArgs string    `yaml:"additionalArgs"`
	Accounts       []account `yaml:"accounts"`
}

type account struct {
	AccountId string            `yaml:"accountId"`
	Name      string            `yaml:"name"`
	Roles     []string          `yaml:"roles"`
	Execs     map[string]string `yaml:"execs"`
}

type templateVars struct {
	AccountId   string
	AccountName string
	AliasName   string
	Args        template.HTML
	ProfileName string
	Role        string
	TeamName    string
}

const (
	aliasTemplate = `
function swamp-{{.AliasName}}() {
  SWAMP_TARGET_PROFILE='{{.ProfileName}}' \
    SWAMP_ACCOUNT='{{.AccountId}}' \
    SWAMP_ACCOUNT_NAME='{{.AccountName}}' \
    SWAMP_TARGET_ROLE='{{.Role}}' \
    swamp {{.Args}}
}
`
)

func generateAliases(w io.Writer, path string) error {
	fmt.Fprintln(w, "# This aliases are generated with swamp")

	c := &aliasConfig{}
	if bytes, err := ioutil.ReadFile(path); err != nil {
		return err
	} else {
		if err := yaml.Unmarshal(bytes, c); err != nil {
			return err
		}

		for _, team := range c.Teams {
			if err := generateAliasTeam(w, c, team); err != nil {
				return err
			}
		}
	}
	return nil
}

func generateAliasTeam(w io.Writer, config *aliasConfig, team team) error {
	for _, account := range team.Accounts {
		if err := generateAliasAccount(w, config, team, account); err != nil {
			return err
		}
	}
	return nil
}

func generateAliasAccount(w io.Writer, config *aliasConfig, team team, account account) error {
	if tpl, err := template.New("aliases").Option("missingkey=error").Parse(aliasTemplate); err != nil {
		return err
	} else {
		for _, role := range account.Roles {
			generateAliasRole(w, config, team, account, role, tpl)
		}
	}
	return nil
}

func generateAliasRole(w io.Writer, config *aliasConfig, team team, account account, role string, tpl *template.Template) {
	re := regexp.MustCompile(`[^a-zA-Z0-9_]`)
	profileName := strings.ToLower(team.Name + "-" + account.Name + "-" + re.ReplaceAllString(role, "-"))
	args := config.AllArgs
	if team.AdditionalArgs != "" {
		args += " " + team.AdditionalArgs
	} else {
		args += " " + config.DefaultAdditionalArgs
	}
	args += " -account '" + account.AccountId + "'"
	args += " -target-role '" + role + "'"
	args += " -target-profile '" + profileName + "'"

	baseArgs := args

	t := templateVars{
		AccountId:   account.AccountId,
		AccountName: account.Name,
		AliasName:   profileName,
		Args:        template.HTML(baseArgs + ` "${@}"`),
		ProfileName: profileName,
		Role:        role,
		TeamName:    team.Name,
	}
	tpl.Execute(w, t)
	generateExecs(w, baseArgs, profileName, tpl, t, config.AllExecs)
	generateExecs(w, baseArgs, profileName, tpl, t, account.Execs)
}

func generateExecs(w io.Writer, baseArgs string, profileName string, tpl *template.Template, t templateVars, execs map[string]string) {
	var keys []string
	for k := range execs {
		keys = append(keys, k)
	}
	sort.Strings(keys)

	for _, k := range keys {
		t.AliasName = profileName + "-" + k
		t.Args = template.HTML(baseArgs + ` -exec "` + execs[k] + `"`)
		tpl.Execute(w, t)
	}
}