dev2 edge: per-site retry holds requests across an app restart; on for group.call (#212)

A site with "retry" gets its own reverse_proxy with lb_try_duration, so
Caddy keeps dialing the app while a deploy restarts it instead of answering
502. group.call needs it: Telnyx webhooks drive live calls.

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

Author: ralyodio

dev2/dev2-edge

@@ -156,7 +156,12 @@ def caddy_site(site, s):
         lines.append("\tencode gzip")
     if site.get("access_log"):
         lines += ["\tlog {", f"\t\toutput file /var/log/caddy/{site['hosts'][0]}.access.log", "\t}"]
-    if "proxy" in site:
+    if "proxy" in site and site.get("retry"):
+        # While the app restarts (a deploy), hold the request and keep dialing instead of
+        # answering 502: webhooks that drive live calls (Telnyx) must not fail mid-call.
+        lines += [f"\treverse_proxy 127.0.0.1:{int(site['proxy'])} {{", "\t\theader_up X-Real-IP {remote_host}",
+                  "\t\tstream_close_delay 1h", f"\t\tlb_try_duration {site['retry']}", "\t\tlb_try_interval 250ms", "\t}"]
+    elif "proxy" in site:
         lines.append(f"\timport edge_proxy {int(site['proxy'])}")
     elif "root" in site:
         lines += [f"\troot * {site['root']}", "\tfile_server"]

dev2/edge/edge.json

@@ -18,8 +18,8 @@
     { "hosts": ["pit.world"], "proxy": 8787, "max_body": "1MiB" },
     { "hosts": ["www.pit.world"], "redirect": "https://pit.world{uri}" },
     { "hosts": ["ad.network.pit.world"], "proxy": 8800, "max_body": "1MiB", "gzip": true },
-    { "hosts": ["group.call.pit.world"], "proxy": 8810, "max_body": "1MiB",
-      "//": "group.call (moshcoder/group.call): no gzip, so the room page's server-sent events are not held back" },
+    { "hosts": ["group.call.pit.world"], "proxy": 8810, "max_body": "1MiB", "retry": "20s",
+      "//": "group.call (moshcoder/group.call): no gzip, so the room page's server-sent events are not held back; retry holds Telnyx webhooks across a deploy instead of 502" },
     { "hosts": ["*.*.pit.world", "*.*.*.pit.world"], "proxy": 8787, "max_body": "30MiB", "gzip": true,
       "//": "pit-proxy: every <name>.pit.world (+ bbs./social.) relayed by the pit.world app; one Let's Encrypt certificate per name from pit-proxy-cert" },
     { "hosts": ["built.indie"], "proxy": 8798, "max_body": "1MiB", "moshpit": true },