frp/pkg/config/v1/value_source.go

94 lines
2.4 KiB
Go

// Copyright 2025 The frp Authors
//
// 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 v1
import (
"context"
"errors"
"fmt"
"os"
"strings"
)
// ValueSource provides a way to dynamically resolve configuration values
// from various sources like files, environment variables, or external services.
type ValueSource struct {
Type string `json:"type"`
File *FileSource `json:"file,omitempty"`
}
// FileSource specifies how to load a value from a file.
type FileSource struct {
Path string `json:"path"`
}
// Validate validates the ValueSource configuration.
func (v *ValueSource) Validate() error {
if v == nil {
return errors.New("valueSource cannot be nil")
}
switch v.Type {
case "file":
if v.File == nil {
return errors.New("file configuration is required when type is 'file'")
}
return v.File.Validate()
default:
return fmt.Errorf("unsupported value source type: %s (only 'file' is supported)", v.Type)
}
}
// Resolve resolves the value from the configured source.
func (v *ValueSource) Resolve(ctx context.Context) (string, error) {
if err := v.Validate(); err != nil {
return "", err
}
switch v.Type {
case "file":
return v.File.Resolve(ctx)
default:
return "", fmt.Errorf("unsupported value source type: %s", v.Type)
}
}
// Validate validates the FileSource configuration.
func (f *FileSource) Validate() error {
if f == nil {
return errors.New("fileSource cannot be nil")
}
if f.Path == "" {
return errors.New("file path cannot be empty")
}
return nil
}
// Resolve reads and returns the content from the specified file.
func (f *FileSource) Resolve(_ context.Context) (string, error) {
if err := f.Validate(); err != nil {
return "", err
}
content, err := os.ReadFile(f.Path)
if err != nil {
return "", fmt.Errorf("failed to read file %s: %v", f.Path, err)
}
// Trim whitespace, which is important for file-based tokens
return strings.TrimSpace(string(content)), nil
}