Forwarder: resolve opencode workspace/session dynamically per request (#28)

ops/forwarder/forwarder.py

@@ -1,6 +1,10 @@
 #!/usr/bin/env python3
 """mesh-bot notify forwarder: POST /notify {text, from?} -> opencode session message (basic auth).
 
+The opencode workspace UUID is regenerated on host restarts, so the target workspace + session are
+resolved dynamically per request via the opencode API (no caching — messages are rare): list
+workspaces, pick the mesh-bot one by path (fallback: name), then its most recently updated session.
+
 Note on semantics: the opencode API accepts a session message immediately but holds the HTTP
 response until the agent turn completes — so a read timeout here means DELIVERED, not failed.
 """
@@ -8,11 +12,43 @@ import json, base64, urllib.request
 from http.server import BaseHTTPRequestHandler, HTTPServer
 import os
 
-BASE = os.environ.get("FORWARDER_BASE", "http://127.0.0.1:9898/workspaces/679fd6f6-b237-4a46-bf69-64cb0fc865b0/instance")
-SESSION = os.environ.get("FORWARDER_SESSION", "ses_f31037caeffeioRwixqGV7VS6m")
+API = os.environ.get("FORWARDER_API", "http://127.0.0.1:9898")
+WORKSPACE_PATH = os.environ.get("FORWARDER_WORKSPACE_PATH", "/home/krzyw/projects/sandbox/mesh-bot")
+SESSION_OVERRIDE = os.environ.get("FORWARDER_SESSION", "")  # when set, skips session discovery
 USER = os.environ["FORWARDER_USER"]   # required; fail fast if missing
 PASS = os.environ["FORWARDER_PASS"]   # required; fail fast if missing
 
+def _auth_headers():
+    return {"Authorization": "Basic " + base64.b64encode(f"{USER}:{PASS}".encode()).decode()}
+
+def _get_json(url):
+    req = urllib.request.Request(url, headers=_auth_headers())
+    try:
+        with urllib.request.urlopen(req, timeout=15) as r:
+            return json.loads(r.read().decode())
+    except Exception as e:
+        raise RuntimeError(f"opencode API unreachable at {url}: {e!r}") from None
+
+def resolve_target():
+    """Resolve (base_url, session_id) fresh per request; raises RuntimeError with a clear reason."""
+    workspaces = _get_json(API + "/api/workspaces")
+    matches = [w for w in workspaces if w.get("path") == WORKSPACE_PATH] or \
+        [w for w in workspaces if w.get("name") == "mesh-bot"]
+    pool = [w for w in matches if w.get("status") == "ready"] or matches
+    if not pool:
+        raise RuntimeError(f"workspace not found: path={WORKSPACE_PATH} name=mesh-bot")
+    base = API + pool[0]["proxyPath"]
+    sid = SESSION_OVERRIDE
+    if not sid:
+        sessions = _get_json(base + "/session")
+        if not sessions:
+            raise RuntimeError(f"no sessions in workspace {pool[0]['id']} ({WORKSPACE_PATH})")
+
+        def updated(s):
+            return (s.get("time") or {}).get("updated") or 0
+        sid = max(sessions, key=updated)["id"] if any(updated(s) for s in sessions) else sessions[0]["id"]
+    return base, sid
+
 class H(BaseHTTPRequestHandler):
     def do_POST(self):
         if self.path != "/notify":
@@ -22,23 +58,27 @@ class H(BaseHTTPRequestHandler):
             body = json.loads(self.rfile.read(n) or b"{}")
             text, frm = body.get("text"), body.get("from")
             msg = 'New mesh message' + (f' from node {frm}' if frm is not None else '') + f': "{text}" — please react to it.'
+            base, sid = resolve_target()  # fresh per request; RuntimeError on API/workspace/session failure
             req = urllib.request.Request(
-                f"{BASE}/session/{SESSION}/message",
+                f"{base}/session/{sid}/message",
                 data=json.dumps({"parts": [{"type": "text", "text": msg}]}).encode(),
-                headers={"Content-Type": "application/json",
-                         "Authorization": "Basic " + base64.b64encode(f"{USER}:{PASS}".encode()).decode()},
+                headers={"Content-Type": "application/json", **_auth_headers()},
                 method="POST")
             try:
                 r = urllib.request.urlopen(req, timeout=15)
                 code = r.status  # headers received => opencode accepted the message
                 try: out = r.read(200).decode(errors='replace')
                 except Exception as e2: out = f'(body read failed after delivery: {e2!r})'
-                print(f"forwarded to opencode session {SESSION}: HTTP {code} {out[:150]!r}", flush=True)
+                print(f"forwarded to opencode session {sid}: HTTP {code} {out[:150]!r}", flush=True)
                 self._reply(code if 200 <= code < 300 else 502, b'{"ok":true}' if 200 <= code < 300 else str(code).encode())
             except TimeoutError:
                 # request was sent; opencode holds the response until the agent turn finishes => delivered
-                print(f"forwarded to opencode session {SESSION}: accepted (response still pending after 15 s)", flush=True)
+                print(f"forwarded to opencode session {sid}: accepted (response still pending after 15 s)", flush=True)
                 self._reply(202, b'{"ok":true,"note":"accepted; opencode response pending"}')
+        except RuntimeError as e:
+            # resolve_target() failure modes: API unreachable / workspace not found / no sessions in workspace
+            print(f"target resolution failed: {e!r}", flush=True)
+            self._reply(502, repr(e).encode())
         except Exception as e:
             print(f"opencode call failed: {e!r}", flush=True)
             self._reply(502, repr(e).encode())