open-vault/command/config.go
Sean Chittenden e7f600b4e6 Improve error handling re: homedir expansion
Useful if the HOME envvar is not set because `vault` was launched in a clean environment (e.g. `env -i vault ...`).
2016-04-25 18:01:13 -07:00

124 lines
3 KiB
Go

package command
import (
"fmt"
"io/ioutil"
"os"
"github.com/hashicorp/go-multierror"
"github.com/hashicorp/hcl"
"github.com/hashicorp/hcl/hcl/ast"
"github.com/mitchellh/go-homedir"
)
const (
// DefaultConfigPath is the default path to the configuration file
DefaultConfigPath = "~/.vault"
// ConfigPathEnv is the environment variable that can be used to
// override where the Vault configuration is.
ConfigPathEnv = "VAULT_CONFIG_PATH"
)
// Config is the CLI configuration for Vault that can be specified via
// a `$HOME/.vault` file which is HCL-formatted (therefore HCL or JSON).
type DefaultConfig struct {
// TokenHelper is the executable/command that is executed for storing
// and retrieving the authentication token for the Vault CLI. If this
// is not specified, then vault's internal token store will be used, which
// stores the token on disk unencrypted.
TokenHelper string `hcl:"token_helper"`
}
// Config loads the configuration and returns it. If the configuration
// is already loaded, it is returned.
func Config() (*DefaultConfig, error) {
var err error
config, err := LoadConfig("")
if err != nil {
return nil, err
}
return config, nil
}
// LoadConfig reads the configuration from the given path. If path is
// empty, then the default path will be used, or the environment variable
// if set.
func LoadConfig(path string) (*DefaultConfig, error) {
if path == "" {
path = DefaultConfigPath
}
if v := os.Getenv(ConfigPathEnv); v != "" {
path = v
}
// NOTE: requires HOME env var to be set
path, err := homedir.Expand(path)
if err != nil {
return nil, fmt.Errorf("Error expanding config path %s: %s", path, err)
}
contents, err := ioutil.ReadFile(path)
if err != nil && !os.IsNotExist(err) {
return nil, err
}
return ParseConfig(string(contents))
}
// ParseConfig parses the given configuration as a string.
func ParseConfig(contents string) (*DefaultConfig, error) {
root, err := hcl.Parse(contents)
if err != nil {
return nil, err
}
// Top-level item should be the object list
list, ok := root.Node.(*ast.ObjectList)
if !ok {
return nil, fmt.Errorf("Failed to parse config: does not contain a root object")
}
valid := []string{
"token_helper",
}
if err := checkHCLKeys(list, valid); err != nil {
return nil, err
}
var c DefaultConfig
if err := hcl.DecodeObject(&c, list); err != nil {
return nil, err
}
return &c, nil
}
func checkHCLKeys(node ast.Node, valid []string) error {
var list *ast.ObjectList
switch n := node.(type) {
case *ast.ObjectList:
list = n
case *ast.ObjectType:
list = n.List
default:
return fmt.Errorf("cannot check HCL keys of type %T", n)
}
validMap := make(map[string]struct{}, len(valid))
for _, v := range valid {
validMap[v] = struct{}{}
}
var result error
for _, item := range list.Items {
key := item.Keys[0].Token.Value().(string)
if _, ok := validMap[key]; !ok {
result = multierror.Append(result, fmt.Errorf(
"invalid key '%s' on line %d", key, item.Assign.Line))
}
}
return result
}