691ff82d89
Signed-off-by: Daniel Nephin <dnephin@docker.com>
Upstream-commit: 0aa7ca943c
Component: cli
109 lines
2.6 KiB
Go
109 lines
2.6 KiB
Go
package interpolation
|
|
|
|
import (
|
|
"os"
|
|
|
|
"github.com/docker/cli/cli/compose/template"
|
|
"github.com/pkg/errors"
|
|
)
|
|
|
|
// Options supported by Interpolate
|
|
type Options struct {
|
|
// SectionName of the configuration section
|
|
SectionName string
|
|
// LookupValue from a key
|
|
LookupValue LookupValue
|
|
}
|
|
|
|
// LookupValue is a function which maps from variable names to values.
|
|
// Returns the value as a string and a bool indicating whether
|
|
// the value is present, to distinguish between an empty string
|
|
// and the absence of a value.
|
|
type LookupValue func(key string) (string, bool)
|
|
|
|
// Interpolate replaces variables in a string with the values from a mapping
|
|
func Interpolate(config map[string]interface{}, opts Options) (map[string]interface{}, error) {
|
|
out := map[string]interface{}{}
|
|
|
|
if opts.LookupValue == nil {
|
|
opts.LookupValue = os.LookupEnv
|
|
}
|
|
|
|
for key, item := range config {
|
|
if item == nil {
|
|
out[key] = nil
|
|
continue
|
|
}
|
|
mapItem, ok := item.(map[string]interface{})
|
|
if !ok {
|
|
return nil, errors.Errorf("Invalid type for %s : %T instead of %T", key, item, out)
|
|
}
|
|
interpolatedItem, err := interpolateSectionItem(key, mapItem, opts)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
out[key] = interpolatedItem
|
|
}
|
|
|
|
return out, nil
|
|
}
|
|
|
|
func interpolateSectionItem(
|
|
sectionkey string,
|
|
item map[string]interface{},
|
|
opts Options,
|
|
) (map[string]interface{}, error) {
|
|
out := map[string]interface{}{}
|
|
|
|
for key, value := range item {
|
|
interpolatedValue, err := recursiveInterpolate(value, opts)
|
|
switch err := err.(type) {
|
|
case nil:
|
|
case *template.InvalidTemplateError:
|
|
return nil, errors.Errorf(
|
|
"Invalid interpolation format for %#v option in %s %#v: %#v. You may need to escape any $ with another $.",
|
|
key, opts.SectionName, sectionkey, err.Template,
|
|
)
|
|
default:
|
|
return nil, errors.Wrapf(err, "error while interpolating %s in %s %s", key, opts.SectionName, sectionkey)
|
|
}
|
|
out[key] = interpolatedValue
|
|
}
|
|
|
|
return out, nil
|
|
}
|
|
|
|
func recursiveInterpolate(value interface{}, opts Options) (interface{}, error) {
|
|
switch value := value.(type) {
|
|
|
|
case string:
|
|
return template.Substitute(value, template.Mapping(opts.LookupValue))
|
|
|
|
case map[string]interface{}:
|
|
out := map[string]interface{}{}
|
|
for key, elem := range value {
|
|
interpolatedElem, err := recursiveInterpolate(elem, opts)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
out[key] = interpolatedElem
|
|
}
|
|
return out, nil
|
|
|
|
case []interface{}:
|
|
out := make([]interface{}, len(value))
|
|
for i, elem := range value {
|
|
interpolatedElem, err := recursiveInterpolate(elem, opts)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
out[i] = interpolatedElem
|
|
}
|
|
return out, nil
|
|
|
|
default:
|
|
return value, nil
|
|
|
|
}
|
|
}
|