rootsystem/configuration/configuration.go

package configuration

import (
	"encoding/json"
	"fmt"
	"io/ioutil"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"syscall"

	errors "git.sequentialread.com/forest/pkg-errors"
)

type Configuration struct {
	Host               HostConfiguration
	ApplicationModules []string
	Terraform          TerraformConfiguration
	ObjectStorage      ObjectStorageConfiguration
	Credentials        []Credential
}

type HostConfiguration struct {
	Name string
}

type TerraformConfiguration struct {
	GlobalModules []string
	LocalModules  []string
	Variables     map[string]string
}

type ObjectStorageConfiguration struct {
	Encryption string
	Backends   []ObjectStorageBackend
}

type ObjectStorageBackend struct {
	Provider string
	Region   string
	Name     string
}

type Credential struct {
	Type     string
	SSID     string
	Username string
	Password string
}

const GANDI = "Gandi"
const DIGITALOCEAN = "DigitalOcean"
const DIGITALOCEAN_API_URL = "https://api.digitalocean.com"
const GANDI_API_URL = "https://api.gandi.net"
const AMAZON_S3 = "AmazonS3"
const BACKBLAZE_B2 = "BackblazeB2"
const OBJECT_STORAGE_PASSPHRASE = "ObjectStoragePassphrase"
const APPLICATION_MODULES_PATH = "application-modules"
const GLOBAL_TERRAFORM_PROJECT = "terraform-global"
const LOCAL_TERRAFORM_PROJECT = "terraform-local"
const TERRAFORM_MODULES = "terraform-modules"
const ANSIBLE_ROLES = "ansible-roles"
const ANSIBLE_PLAYBOOK_FILE_NAME = "playbook.yml"
const TERRAFORM_PLAN_FILE_NAME = "terraform-plan-file"
const ANSIBLE_WRAPPER_PATH = "ansible-wrapper"
const DOCKER_SOCKET = "/var/run/docker.sock"
const THRESHOLD_SOCKET = "/var/run/servergarden/threshold/threshold.sock"
const CADDY_SOCKET = "/var/run/servergarden/caddy/caddy.sock"
const CADDY_DATA = "/var/lib/servergarden/caddy/data/"
const THRESHOLD_DATA = "/var/lib/servergarden/threshold/"
const TERRAFORM_APPLY_STATUS_UPDATE_INTERVAL_SECONDS = 5

func GET_ANSIBLE_WRAPPER_FILES() []string {
	return []string{
		"ansible-playbook-wrapper",
		"callback_plugins",
		"ansible.cfg",
	}
}

const SSH_KEYS_PATH = "ssh"
const TERRAFORM_STATE_SERVER_PORT_NUMBER = 6471

func LoadConfiguration() (*Configuration, string, error) {

	if runtime.GOOS == "windows" {
		return nil, "", errors.New("windows operating system is not supported.")
	}

	workingDirectory, err := os.Getwd()
	if err != nil {
		return nil, "", errors.Wrap(err, "can't os.Getwd()")
	}
	executableDirectory, err := getCurrentExecDir()
	if err != nil {
		return nil, "", errors.Wrap(err, "can't getCurrentExecDir()")
	}

	configFileLocation1 := filepath.Join(executableDirectory, "config.json")
	configFileLocation2 := filepath.Join(workingDirectory, "config.json")

	configFileLocation := configFileLocation1
	configFileStat, err := os.Stat(configFileLocation)
	workingDirectoryToReturn := executableDirectory
	if err != nil || !configFileStat.Mode().IsRegular() {
		configFileLocation = configFileLocation2
		configFileStat, err = os.Stat(configFileLocation)
		workingDirectoryToReturn = workingDirectory
	}
	if err != nil || !configFileStat.Mode().IsRegular() {
		return nil, workingDirectoryToReturn, fmt.Errorf("no config file. checked %s and %s", configFileLocation1, configFileLocation2)
	}

	// configFileUid, err := getUID(configFileStat)
	// if err != nil {
	//   return nil, errors.Wrapf(err, "can't getUID() config file %s", configFileLocation)
	// }
	// if configFileUid != 0 {
	//   return nil, fmt.Errorf("can't start rootsystem: the config file %s is not owned by root.", configFileLocation)
	// }

	// ownerReadWriteOnlyPermissionsOctal := "600"
	// configFilePermissionsOctal := fmt.Sprintf("%o", configFileStat.Mode().Perm())
	// if configFilePermissionsOctal != ownerReadWriteOnlyPermissionsOctal {
	//   return nil, fmt.Errorf(
	//     "can't start rootsystem: the config file %s had permissions %s. expected %s. %s",
	//     configFileLocation,
	//     configFilePermissionsOctal,
	//     ownerReadWriteOnlyPermissionsOctal,
	//     "(config file should only be readable and writable by the owner, aka the root user)",
	//   )
	// }

	jsonBytes, err := ioutil.ReadFile(configFileLocation)
	if err != nil {
		return nil, workingDirectoryToReturn, errors.Wrap(err, "can't read config file")
	}

	var config Configuration
	err = json.Unmarshal(jsonBytes, &config)
	if err != nil {
		return nil, workingDirectoryToReturn, errors.Wrap(err, "can't json.Unmarshal config file")
	}

	return &config, workingDirectoryToReturn, nil
}

func getUID(fileInfo os.FileInfo) (int, error) {
	stat, ok := fileInfo.Sys().(*syscall.Stat_t)
	if !ok {
		return -1, fmt.Errorf("can't cast os.Stat(\"%s\").Sys() to *syscall.Stat_t")
	}

	return int(stat.Uid), nil
}

func getCurrentExecDir() (dir string, err error) {
	path, err := exec.LookPath(os.Args[0])
	if err != nil {
		fmt.Printf("exec.LookPath(%s) returned %s\n", os.Args[0], err)
		return "", err
	}

	absPath, err := filepath.Abs(path)
	if err != nil {
		fmt.Printf("filepath.Abs(%s) returned %s\n", path, err)
		return "", err
	}

	dir = filepath.Dir(absPath)

	return dir, nil
}