# API 与 Rust Runtime 内部通信协议

## 1. 概述

本文档定义主 API 与 Rust Heavy Runtime 之间的内部 HTTP 通信协议。

通信方向：
- Runtime → API：拉取 Job、提交结果、提交日志
- API → Runtime：健康检查（可选）

## 2. 鉴权

所有 `/internal/runtime/*` 接口使用 `InternalAuthGuard`。

**请求头**：
```
x-internal-api-key: <RUNTIME_SERVICE_TOKEN>
x-runtime-instance-id: runtime-001
```

- `x-internal-api-key`：与 API 环境变量 `INTERNAL_API_KEY` 一致
- `x-runtime-instance-id`：Runtime 实例标识，记录到日志

**安全约束**：
- 普通用户 JWT 不可访问 internal 接口
- service token 不可访问普通用户 API
- Runtime 不可通过 internal 接口访问非当前 job 所需数据

## 3. 错误响应格式

所有 internal 接口失败时返回：

```json
{
  "statusCode": 400,
  "errorCode": "INVALID_SNAPSHOT",
  "message": "Snapshot has expired for this job",
  "timestamp": "2026-06-11T10:00:00.000Z"
}
```

### 错误码

| 错误码 | HTTP | 说明 | retryable |
|--------|------|------|-----------|
| `JOB_NOT_FOUND` | 404 | Job 不存在 | false |
| `JOB_ALREADY_LOCKED` | 409 | 已被其他 Runtime 锁定 | true |
| `SNAPSHOT_EXPIRED` | 410 | 快照已过期 | true |
| `SNAPSHOT_NOT_FOUND` | 404 | 快照不存在 | false |
| `CREDENTIAL_NOT_FOUND` | 404 | 凭证不存在 | false |
| `CREDENTIAL_INVALID` | 422 | 凭证无效 | false |
| `RESULT_ALREADY_EXISTS` | 409 | 重复提交 | false |
| `RESULT_SCHEMA_UNSUPPORTED` | 422 | schema 版本不支持 | false |
| `RUNTIME_VERSION_INCOMPATIBLE` | 422 | Runtime 版本不兼容 | false |
| `INTERNAL_ERROR` | 500 | 内部错误 | true |

## 4. 接口详情

### 4.1 Poll Jobs

```
POST /internal/runtime/jobs/poll
```

Runtime 拉取待执行 job。API 根据 Runtime 的 `supportedJobTypes` 和 `capabilities` 过滤兼容的 job。

**请求**：
```json
{
  "runtimeInstanceId": "runtime-001",
  "supportedJobTypes": ["learning_state_analysis", "quiz_generation"],
  "limit": 5,
  "capabilities": {
    "supportedSnapshotVersions": ["ai_snapshot_v1"],
    "supportedOutputSchemaVersions": ["analysis_output_v1", "quiz_output_v1"]
  }
}
```

**响应 200**：
```json
{
  "jobs": [
    {
      "id": "job-abc123",
      "jobType": "learning_state_analysis",
      "targetType": "material",
      "targetId": "mat-xyz",
      "priority": 0,
      "snapshotId": "snap-001",
      "promptVersion": "learning_state_v1",
      "outputSchemaVersion": "analysis_output_v1"
    }
  ]
}
```

### 4.2 Lock Job

```
POST /internal/runtime/jobs/{jobId}/lock
```

Runtime 锁定一个 job，获取执行权。

**请求**：
```json
{
  "runtimeInstanceId": "runtime-001"
}
```

**响应 200**：
```json
{
  "jobId": "job-abc123",
  "status": "locked",
  "lockUntil": 1700000000123
}
```

### 4.3 Heartbeat

```
POST /internal/runtime/jobs/{jobId}/heartbeat
```

Runtime 延长 lock 有效期。

**请求**：
```json
{
  "runtimeInstanceId": "runtime-001"
}
```

**响应 204**：空 body，仅延长 `lockUntil`。

### 4.4 Get Snapshot

```
GET /internal/runtime/jobs/{jobId}/snapshot
```

Runtime 获取 job 关联的 LearningAnalysisSnapshot。

**响应 200**：
```json
{
  "jobId": "job-abc123",
  "snapshotId": "snap-001",
  "snapshotVersion": "ai_snapshot_v1",
  "privacyScope": { "allowDocumentContent": true },
  "userProfile": { "learningGoal": "exam", "currentLevel": "intermediate" },
  "aiSettings": { "allowAiAnalysis": true },
  "learningBehaviorSummary": { "totalActiveSeconds": 3600 },
  "materialProgressSummary": { "progress": 0.6 },
  "behaviorSignals": { "engagementSignal": "high" },
  "scoreSignals": { "masteryRiskScore": 0.3 },
  "constraints": { "dailyAvailableMinutes": 60 },
  "allowedModelFields": ["learningGoal", "currentLevel"]
}
```

**错误**：
- `404 SNAPSHOT_NOT_FOUND` — 快照不存在
- `410 SNAPSHOT_EXPIRED` — 快照已过期，Runtime 应提交 retryable fail

### 4.5 Resolve Credential

```
POST /internal/runtime/model-credentials/resolve
```

Runtime 获取模型调用凭证。platform_key 模式返回平台 key；user_deepseek_key 模式解密用户 key 后返回。

**请求**：
```json
{
  "jobId": "job-abc123",
  "apiKeyMode": "user_deepseek_key",
  "credentialId": "cred-001",
  "provider": "deepseek"
}
```

**响应 200**：
```json
{
  "provider": "deepseek",
  "model": "deepseek-chat",
  "baseUrl": "https://api.deepseek.com/v1",
  "apiKey": "sk-xxxx",
  "apiKeyMode": "user_deepseek_key"
}
```

**安全要求**：
- 明文 `apiKey` 只在响应中短暂出现，不写日志
- `apiKey` 不返回给 iOS / Admin
- 用户 key 必须属于 `job.userId`
- platform key 由 Runtime 环境变量优先使用，API 可选返回

**错误**：
- `404 CREDENTIAL_NOT_FOUND`
- `422 CREDENTIAL_INVALID`

### 4.6 Submit Result

```
POST /internal/runtime/jobs/{jobId}/result
```

Runtime 提交执行成功的结果。

**请求**：
```json
{
  "runtimeInstanceId": "runtime-001",
  "schemaVersion": "analysis_output_v1",
  "status": "succeeded",
  "rawOutput": { "learningState": "in_progress", "confidence": 0.85 },
  "validatedOutput": { "learningState": "in_progress", "riskLevel": "low" },
  "validationErrors": [],
  "usage": {
    "inputTokens": 1200,
    "outputTokens": 450,
    "totalTokens": 1650,
    "latencyMs": 3200,
    "costEstimate": 3
  },
  "attemptNo": 0,
  "outputHash": "sha256-abc123"
}
```

**幂等规则**：
- `resultIdempotencyKey = jobId + attemptNo + outputHash`
- 相同 key 重复提交返回 200（幂等）
- 已有 succeeded result 且 outputHash 不同返回 409 `RESULT_ALREADY_EXISTS`

**响应 201**：created

**错误**：
- `409 RESULT_ALREADY_EXISTS`
- `422 RESULT_SCHEMA_UNSUPPORTED`

### 4.7 Submit Failure

```
POST /internal/runtime/jobs/{jobId}/fail
```

Runtime 提交执行失败的原因。

**请求**：
```json
{
  "runtimeInstanceId": "runtime-001",
  "errorCode": "MODEL_TIMEOUT",
  "errorMessage": "DeepSeek request timed out after 30s",
  "retryable": true,
  "rawError": "connection timeout"
}
```

**处理规则**：
- `retryable=true` 且 `retryCount < maxRetryCount`：job 回到 `pending`
- `retryable=false` 或达到 maxRetryCount：job 变为 `failed`
- `rawError` 中不得包含 apiKey

**响应 200**：acknowledged

### 4.8 Submit Invocation Logs

```
POST /internal/runtime/invocation-logs
```

Runtime 提交模型调用日志（批量）。

**请求**：
```json
{
  "logs": [
    {
      "jobId": "job-abc123",
      "provider": "deepseek",
      "model": "deepseek-chat",
      "apiKeyMode": "user_deepseek_key",
      "credentialId": "cred-001",
      "promptName": "learning_state_analysis",
      "promptVersion": "learning_state_v1",
      "outputSchemaVersion": "analysis_output_v1",
      "inputTokens": 1200,
      "outputTokens": 450,
      "totalTokens": 1650,
      "latencyMs": 3200,
      "costEstimate": 3,
      "success": true,
      "retryCount": 0,
      "runtimeInstanceId": "runtime-001",
      "traceId": "trace-xyz",
      "correlationId": "corr-abc"
    }
  ]
}
```

**约束**：
- 不允许 `apiKey` 字段
- 失败调用也要提交日志
- 日志提交失败不导致主任务崩溃

**响应 201**：created

### 4.9 Health（可选）

```
GET /internal/runtime/health
```

API 查询 Runtime 健康状态。此接口由 Runtime 暴露（非 API 暴露）。

**响应 200**：
```json
{
  "runtimeInstanceId": "runtime-001",
  "status": "ok",
  "version": "0.1.0",
  "startedAt": 1700000000000,
  "lastJobAt": 1700000000123,
  "activeJobs": 2
}
```

## 5. 接口总览

| 方法 | 路径 | 调用方 | 鉴权 |
|------|------|--------|------|
| POST | `/internal/runtime/jobs/poll` | Runtime | InternalAuthGuard |
| POST | `/internal/runtime/jobs/{jobId}/lock` | Runtime | InternalAuthGuard |
| POST | `/internal/runtime/jobs/{jobId}/heartbeat` | Runtime | InternalAuthGuard |
| GET | `/internal/runtime/jobs/{jobId}/snapshot` | Runtime | InternalAuthGuard |
| POST | `/internal/runtime/model-credentials/resolve` | Runtime | InternalAuthGuard |
| POST | `/internal/runtime/jobs/{jobId}/result` | Runtime | InternalAuthGuard |
| POST | `/internal/runtime/jobs/{jobId}/fail` | Runtime | InternalAuthGuard |
| POST | `/internal/runtime/invocation-logs` | Runtime | InternalAuthGuard |
| GET | `/internal/runtime/health` | API | —（检查外部 Runtime） |

## 6. 验收清单

- [x] 所有 internal 接口有 DTO 定义（`runtime-internal.dto.ts`）
- [x] 所有 internal 接口有鉴权设计（复用 InternalAuthGuard）
- [x] 所有失败返回包含 errorCode / message
- [x] Runtime result 支持结构化 payload（validatedOutput）
- [x] Runtime failure 支持 retryable 标记
- [x] Credential resolve 接口明确不记录明文 key
- [x] 接口命名、字段命名与 Runtime 项目可直接对齐