split aria2 adapter helpers

internal/service/aria2_rpc.go

@@ -0,0 +1,166 @@
+package service
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+)
+
+// aria2Request 是 Aria2 JSON-RPC 请求结构。
+type aria2Request struct {
+	JSONRPC string        `json:"jsonrpc"`
+	Method  string        `json:"method"`
+	ID      string        `json:"id"`
+	Params  []interface{} `json:"params"`
+}
+
+// aria2Response 是 Aria2 JSON-RPC 响应结构。
+type aria2Response struct {
+	JSONRPC string          `json:"jsonrpc"`
+	ID      string          `json:"id"`
+	Result  json.RawMessage `json:"result"`
+	Error   *aria2Error     `json:"error"`
+}
+
+// aria2Error 是 Aria2 JSON-RPC 错误结构。
+type aria2Error struct {
+	Code    int    `json:"code"`
+	Message string `json:"message"`
+}
+
+// Initialize 配置并初始化 Aria2 RPC 连接。
+func (a *Aria2Adapter) Initialize(ctx context.Context, cfg DownloadClientConfig) error {
+	a.mu.Lock()
+	defer a.mu.Unlock()
+	endpoint, err := normalizeDownloadClientEndpoint("aria2", cfg.Host)
+	if err != nil {
+		return err
+	}
+	cfg.Host = endpoint
+	a.cfg = cfg
+	a.idSeq = 0
+	return a.getVersionLocked(ctx)
+}
+
+// Ping 测试连接。
+func (a *Aria2Adapter) Ping(ctx context.Context) error {
+	a.mu.Lock()
+	defer a.mu.Unlock()
+	return a.getVersionLocked(ctx)
+}
+
+// getVersionLocked 内部版本检查（调用者必须持有锁）。
+func (a *Aria2Adapter) getVersionLocked(ctx context.Context) error {
+	rpcURL, err := downloadClientRPCURL("aria2", a.cfg.Host)
+	if err != nil {
+		return err
+	}
+
+	req := &aria2Request{
+		JSONRPC: "2.0",
+		Method:  "aria2.getVersion",
+		ID:      a.nextID(),
+		Params:  []interface{}{"token:" + a.cfg.Password},
+	}
+
+	body, err := json.Marshal(req)
+	if err != nil {
+		return err
+	}
+
+	httpReq, err := newDownloadClientHTTPRequest(ctx, http.MethodPost, rpcURL, bytes.NewReader(body))
+	if err != nil {
+		return err
+	}
+	httpReq.Header.Set("Content-Type", "application/json")
+	if a.cfg.Username != "" {
+		httpReq.SetBasicAuth(a.cfg.Username, a.cfg.Password)
+	}
+
+	resp, err := a.client.Do(httpReq)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+	if resp.StatusCode >= 400 {
+		return fmt.Errorf("aria2 rpc: %d", resp.StatusCode)
+	}
+	return nil
+}
+
+// rpcLocked 发送 JSON-RPC 请求（调用者必须持有锁）。
+func (a *Aria2Adapter) rpcLocked(ctx context.Context, method string, params []interface{}) (json.RawMessage, error) {
+	rpcURL, err := downloadClientRPCURL("aria2", a.cfg.Host)
+	if err != nil {
+		return nil, err
+	}
+
+	if params == nil {
+		params = []interface{}{}
+	}
+
+	// 如果 secret 不在 params 中，添加到第一位
+	if len(params) > 0 {
+		if secret, ok := params[0].(string); ok && strings.HasPrefix(secret, "token:") {
+			// 已经有 secret
+		} else {
+			newParams := make([]interface{}, 0, len(params)+1)
+			newParams = append(newParams, "token:"+a.cfg.Password)
+			newParams = append(newParams, params...)
+			params = newParams
+		}
+	} else {
+		params = []interface{}{"token:" + a.cfg.Password}
+	}
+
+	req := &aria2Request{
+		JSONRPC: "2.0",
+		Method:  method,
+		ID:      a.nextID(),
+		Params:  params,
+	}
+
+	body, err := json.Marshal(req)
+	if err != nil {
+		return nil, err
+	}
+
+	httpReq, err := newDownloadClientHTTPRequest(ctx, http.MethodPost, rpcURL, bytes.NewReader(body))
+	if err != nil {
+		return nil, err
+	}
+	httpReq.Header.Set("Content-Type", "application/json")
+	if a.cfg.Username != "" {
+		httpReq.SetBasicAuth(a.cfg.Username, a.cfg.Password)
+	}
+
+	resp, err := a.client.Do(httpReq)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	respBody, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	var rpcResp aria2Response
+	if err := json.Unmarshal(respBody, &rpcResp); err != nil {
+		return nil, err
+	}
+	if rpcResp.Error != nil {
+		return nil, fmt.Errorf("aria2 rpc error [%d]: %s", rpcResp.Error.Code, rpcResp.Error.Message)
+	}
+	return rpcResp.Result, nil
+}
+
+// nextID 生成递增的请求 ID。
+func (a *Aria2Adapter) nextID() string {
+	a.idSeq++
+	return fmt.Sprintf("msg-%d", a.idSeq)
+}