feat(channels): add Discord channel (Exa search + public Invite API) (#230)

Zero-config channel (tier=0). Uses Discord Invite API to read public server info (no auth), and Exa via mcporter for content search. Tested: discord.gg/python returns 419K members, description, channel. 104 tests passing. Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-03-31 15:16:15 +08:00
parent f4b3758478
commit 66883060bc
3 changed files with 186 additions and 0 deletions
@@ -0,0 +1,97 @@
+# -*- coding: utf-8 -*-
+"""Discord channel — search via Exa, read public server info via Invite API."""
+
+import json
+import shutil
+import subprocess
+import urllib.request
+from typing import Tuple
+
+from .base import Channel
+
+_UA = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36"
+_INVITE_API = "https://discord.com/api/v10/invites/{code}?with_counts=true"
+
+
+def _exa_available() -> bool:
+    mcporter = shutil.which("mcporter")
+    if not mcporter:
+        return False
+    try:
+        r = subprocess.run(
+            [mcporter, "config", "list"],
+            capture_output=True, text=True, timeout=5
+        )
+        return "exa" in r.stdout.lower()
+    except Exception:
+        return False
+
+
+def _get_invite_code(url: str) -> str:
+    """Extract invite code from discord.gg/xxx or discord.com/invite/xxx URLs."""
+    url = url.rstrip("/")
+    for prefix in ("discord.gg/", "discord.com/invite/"):
+        if prefix in url:
+            return url.split(prefix)[-1].split("/")[0].split("?")[0]
+    return ""
+
+
+class DiscordChannel(Channel):
+    name = "discord"
+    description = "Discord 服务器信息与内容搜索"
+    backends = ["Exa via mcporter (搜索)", "Discord Invite API (服务器信息)"]
+    tier = 0
+
+    def can_handle(self, url: str) -> bool:
+        return "discord.gg" in url or "discord.com" in url
+
+    def check(self, config=None) -> Tuple[str, str]:
+        if _exa_available():
+            return "ok", "Discord 可用：Exa 搜索内容，Invite API 读取公开服务器信息"
+        return "warn", (
+            "Discord Invite API 可用（无需配置），但搜索功能需要 mcporter + Exa MCP。"
+            "运行 `agent-reach install --env=auto` 安装 Exa。"
+        )
+
+    def read(self, url: str) -> str:
+        """读取 Discord 服务器公开信息（Invite API）或通过 Jina 读取页面。"""
+        code = _get_invite_code(url)
+        if code:
+            api_url = _INVITE_API.format(code=code)
+            req = urllib.request.Request(api_url, headers={"User-Agent": _UA})
+            with urllib.request.urlopen(req, timeout=10) as resp:
+                data = json.loads(resp.read().decode("utf-8"))
+            guild = data.get("guild", {})
+            channel = data.get("channel", {})
+            members = data.get("approximate_member_count", "未知")
+            online = data.get("approximate_presence_count", "未知")
+            return (
+                f"# {guild.get('name', '未知服务器')}\n\n"
+                f"**描述**: {guild.get('description') or '无'}\n"
+                f"**成员**: {members:,} 人（在线 {online:,}）\n"
+                f"**频道**: #{channel.get('name', '未知')}\n"
+                f"**邀请链接**: {url}\n"
+            )
+        # Fallback: Jina Reader
+        if not url.startswith(("http://", "https://")):
+            url = "https://" + url
+        jina_url = f"https://r.jina.ai/{url}"
+        req = urllib.request.Request(
+            jina_url, headers={"User-Agent": _UA, "Accept": "text/plain"}
+        )
+        with urllib.request.urlopen(req, timeout=15) as resp:
+            return resp.read().decode("utf-8")
+
+    def search(self, query: str, limit: int = 5) -> str:
+        """通过 Exa 搜索 Discord 内容（服务器、帖子、讨论）。"""
+        mcporter = shutil.which("mcporter")
+        if not mcporter:
+            return "搜索需要 mcporter，请运行 `npm install -g mcporter` 安装。"
+        cmd = (
+            f"mcporter call 'exa.web_search_exa("
+            f"query: \"{query} site:discord.com OR site:discord.gg\", "
+            f"numResults: {limit}, "
+            f"includeDomains: [\"discord.com\", \"discord.gg\"])'"
+        )
+        r = subprocess.run(cmd, shell=True, capture_output=True, text=True, timeout=30)
+        return r.stdout or r.stderr