pulumi/sdk/go/common/util/mapper/object.go

63 lines
2.4 KiB
Go

// Copyright 2016-2018, Pulumi Corporation.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package mapper
import (
"reflect"
)
// AsObject attempts to coerce an existing value to an object map, returning a non-nil error if it cannot be done.
func AsObject(v interface{}, ty reflect.Type, key string) (map[string]interface{}, FieldError) {
if vmap, ok := v.(map[string]interface{}); ok {
return vmap, nil
}
return nil, NewWrongTypeError(
ty, key, reflect.TypeOf(make(map[string]interface{})), reflect.TypeOf(v))
}
// AsString attempts to coerce an existing value to a string, returning a non-nil error if it cannot be done.
func AsString(v interface{}, ty reflect.Type, key string) (*string, FieldError) {
if s, ok := v.(string); ok {
return &s, nil
}
return nil, NewWrongTypeError(ty, key, reflect.TypeOf(""), reflect.TypeOf(v))
}
// FieldObject looks up a field by name within an object map, coerces it to an object itself, and returns it. If the
// field exists but is not an object map, or it is missing and optional is false, a non-nil error is returned.
func FieldObject(obj map[string]interface{}, ty reflect.Type,
key string, optional bool,
) (map[string]interface{}, FieldError) {
if o, has := obj[key]; has {
return AsObject(o, ty, key)
} else if !optional {
// The field doesn't exist and yet it is required; issue an error.
return nil, NewMissingError(ty, key)
}
return nil, nil
}
// FieldString looks up a field by name within an object map, coerces it to a string, and returns it. If the
// field exists but is not a string, or it is missing and optional is false, a non-nil error is returned.
func FieldString(obj map[string]interface{}, ty reflect.Type, key string, optional bool) (*string, FieldError) {
if s, has := obj[key]; has {
return AsString(s, ty, key)
} else if !optional {
// The field doesn't exist and yet it is required; issue an error.
return nil, NewMissingError(ty, key)
}
return nil, nil
}