feat(ai-pull-request): 以 opencode 分析 diff 自動產生並建立 Pull Request

2026-06-26 11:42:05 +08:00
parent 5db3b328a2
commit d42ccd8b08
10 changed files with 887 additions and 27 deletions
@@ -0,0 +1,230 @@
+import { writeFileSync, mkdtempSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { run, log, maskSecrets } from './util.js';
+
+/**
+ * 透過 opencode CLI 分析 git diff，產生 PR 標題與描述。
+ */
+export class OpenCode {
+  /**
+   * @param {object} opts
+   * @param {string} opts.baseUrl
+   * @param {string} opts.model
+   * @param {string} opts.provider
+   * @param {string} [opts.language]
+   */
+  constructor({ baseUrl, model, provider, language = 'Traditional Chinese (繁體中文)' }) {
+    this.baseUrl = baseUrl;
+    this.model = model;
+    this.provider = provider;
+    this.language = language;
+  }
+
+  /** 是否有足夠設定可以呼叫 opencode。 */
+  isConfigured() {
+    return Boolean(this.baseUrl && this.model && this.provider);
+  }
+
+  /**
+   * 在暫存目錄寫出 opencode.json，將自訂 provider 設為 OpenAI 相容端點。
+   *
+   * @returns {string} config 檔路徑
+   */
+  _writeConfig() {
+    const dir = mkdtempSync(join(tmpdir(), 'opencode-'));
+    const options = { baseURL: this.baseUrl };
+
+    const config = {
+      $schema: 'https://opencode.ai/config.json',
+      provider: {
+        [this.provider]: {
+          npm: '@ai-sdk/openai-compatible',
+          name: this.provider,
+          options,
+          models: {
+            [this.model]: { name: this.model },
+          },
+        },
+      },
+    };
+
+    const path = join(dir, 'opencode.json');
+    writeFileSync(path, JSON.stringify(config, null, 2));
+    return path;
+  }
+
+  /**
+   * 呼叫 opencode 產生標題與描述。
+   *
+   * @param {object} ctx
+   * @param {string} ctx.sourceBranch
+   * @param {string} ctx.targetBranch
+   * @param {string} ctx.commitMessages
+   * @param {string} ctx.diffStat
+   * @param {string} ctx.diff 已截斷的 diff
+   * @returns {Promise<{ title: string, description: string } | null>}
+   */
+  async summarize(ctx) {
+    if (!this.isConfigured()) {
+      log.warn('opencode 參數不完整（需要 base_url / model / provider），略過 AI 摘要');
+      return null;
+    }
+
+    const configPath = this._writeConfig();
+    const prompt = buildPrompt({ ...ctx, language: this.language });
+
+    log.info(`呼叫 opencode（${this.provider}/${this.model}）分析 diff...`);
+    const result = run(
+      'opencode',
+      ['run', '--model', `${this.provider}/${this.model}`, prompt],
+      {
+        cwd: tmpdir(),
+        env: {
+          ...process.env,
+          OPENCODE_CONFIG: configPath,
+          // 確保 opencode 有可寫的 HOME / 設定目錄
+          HOME: process.env.HOME || '/root',
+        },
+        timeout: 5 * 60 * 1000,
+      },
+    );
+
+    if (result.status !== 0) {
+      log.warn(`opencode 執行失敗 (${result.status})：${maskSecrets(result.stderr).slice(0, 500)}`);
+      return null;
+    }
+
+    const parsed = extractResult(result.stdout);
+    if (!parsed) {
+      log.warn('無法從 opencode 輸出解析出標題/描述');
+      return null;
+    }
+    return parsed;
+  }
+}
+
+function buildPrompt({ sourceBranch, targetBranch, commitMessages, diffStat, diff, language }) {
+  return [
+    `You are an assistant that writes high-quality Pull Request titles and descriptions.`,
+    `Analyze the following git changes for a PR merging branch "${sourceBranch}" into "${targetBranch}".`,
+    ``,
+    `Write the title and description in ${language}.`,
+    `The title should be a concise one-line summary (ideally following Conventional Commits style, e.g. "feat: ...").`,
+    `The description should be Markdown and include: a short summary, a bullet list of key changes, and any notable impact or risk.`,
+    ``,
+    `Respond with ONLY a single JSON object, no code fences, no extra text:`,
+    `{"title": "...", "description": "..."}`,
+    ``,
+    `=== Commits ===`,
+    commitMessages || '(no commit messages)',
+    ``,
+    `=== Changed files (stat) ===`,
+    diffStat || '(no stat)',
+    ``,
+    `=== Diff ===`,
+    diff || '(no diff)',
+  ].join('\n');
+}
+
+/** 去除 ANSI 控制碼。 */
+function stripAnsi(text) {
+  // eslint-disable-next-line no-control-regex
+  return text.replace(/\x1b\[[0-9;]*[a-zA-Z]/g, '');
+}
+
+/**
+ * 從 opencode 輸出中擷取含 title 的 JSON 物件並解析。
+ *
+ * @param {string} stdout
+ * @returns {{ title: string, description: string } | null}
+ */
+export function extractResult(stdout) {
+  const text = stripAnsi(stdout || '');
+
+  // 掃描所有平衡的 {...} 區塊，挑出第一個能成功解析且含 title 的物件
+  for (const candidate of findJsonObjects(text)) {
+    // LLM 常在字串值內輸出未跳脫的換行，先嘗試原始解析，失敗再嘗試修正
+    for (const variant of [candidate, escapeControlCharsInStrings(candidate)]) {
+      try {
+        const obj = JSON.parse(variant);
+        if (obj && typeof obj === 'object' && obj.title) {
+          return {
+            title: String(obj.title).trim(),
+            description: String(obj.description || '').trim(),
+          };
+        }
+      } catch {
+        // 試下一個變體 / 候選
+      }
+    }
+  }
+  return null;
+}
+
+/** 將字串值內未跳脫的控制字元（換行、tab 等）跳脫，修正 LLM 常見的無效 JSON。 */
+function escapeControlCharsInStrings(text) {
+  let out = '';
+  let inString = false;
+  let escape = false;
+  for (let i = 0; i < text.length; i++) {
+    const ch = text[i];
+    if (inString) {
+      if (escape) {
+        out += ch;
+        escape = false;
+        continue;
+      }
+      if (ch === '\\') {
+        out += ch;
+        escape = true;
+        continue;
+      }
+      if (ch === '"') {
+        out += ch;
+        inString = false;
+        continue;
+      }
+      if (ch === '\n') { out += '\\n'; continue; }
+      if (ch === '\r') { out += '\\r'; continue; }
+      if (ch === '\t') { out += '\\t'; continue; }
+      out += ch;
+    } else {
+      out += ch;
+      if (ch === '"') inString = true;
+    }
+  }
+  return out;
+}
+
+/** 以括號平衡方式找出文字中所有最外層的 {...} 區塊。 */
+function findJsonObjects(text) {
+  const objects = [];
+  let depth = 0;
+  let start = -1;
+  let inString = false;
+  let escape = false;
+
+  for (let i = 0; i < text.length; i++) {
+    const ch = text[i];
+    if (inString) {
+      if (escape) escape = false;
+      else if (ch === '\\') escape = true;
+      else if (ch === '"') inString = false;
+      continue;
+    }
+    if (ch === '"') {
+      inString = true;
+    } else if (ch === '{') {
+      if (depth === 0) start = i;
+      depth++;
+    } else if (ch === '}') {
+      depth--;
+      if (depth === 0 && start !== -1) {
+        objects.push(text.slice(start, i + 1));
+        start = -1;
+      }
+    }
+  }
+  return objects;
+}