fix(packaging): move templates/ into decnet/ package so they ship with pip install

The docker build contexts and syslog_bridge.py lived at repo root, which
meant setuptools (include = ["decnet*"]) never shipped them. Agents
installed via `pip install $RELEASE_DIR` got site-packages/decnet/** but no
templates/, so every deploy blew up in deployer._sync_logging_helper with
FileNotFoundError on templates/syslog_bridge.py.

Move templates/ -> decnet/templates/ and declare it as setuptools
package-data. Path resolutions in services/*.py and engine/deployer.py drop
one .parent since templates now lives beside the code. Test fixtures,
bandit exclude path, and coverage omit glob updated to match.

decnet/templates/postgres/Dockerfile

@@ -0,0 +1,23 @@
+ARG BASE_IMAGE=debian:bookworm-slim
+FROM ${BASE_IMAGE}
+
+RUN apt-get update && apt-get install -y --no-install-recommends \
+    python3 \
+    && rm -rf /var/lib/apt/lists/*
+
+COPY syslog_bridge.py /opt/syslog_bridge.py
+COPY server.py /opt/server.py
+COPY entrypoint.sh /entrypoint.sh
+RUN chmod +x /entrypoint.sh
+
+EXPOSE 5432
+RUN useradd -r -s /bin/false -d /opt logrelay \
+ && apt-get update && apt-get install -y --no-install-recommends libcap2-bin \
+ && rm -rf /var/lib/apt/lists/* \
+ && (find /usr/bin/ -maxdepth 1 -name 'python3*' -type f -exec setcap 'cap_net_bind_service+eip' {} \; 2>/dev/null || true)
+
+HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
+  CMD kill -0 1 || exit 1
+
+USER logrelay
+ENTRYPOINT ["/entrypoint.sh"]

decnet/templates/postgres/entrypoint.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+set -e
+exec python3 /opt/server.py

decnet/templates/postgres/server.py

@@ -0,0 +1,119 @@
+#!/usr/bin/env python3
+"""
+PostgreSQLserver.
+Reads the startup message, extracts username and database, responds with
+an AuthenticationMD5Password challenge, logs the hash sent back, then
+returns an error. Logs all interactions as JSON.
+"""
+
+import asyncio
+import os
+import struct
+from syslog_bridge import syslog_line, write_syslog_file, forward_syslog
+
+NODE_NAME = os.environ.get("NODE_NAME", "pgserver")
+SERVICE_NAME   = "postgres"
+LOG_TARGET = os.environ.get("LOG_TARGET", "")
+PORT = int(os.environ.get("PORT", "5432"))
+def _error_response(message: str) -> bytes:
+    body = b"S" + b"FATAL\x00" + b"M" + message.encode() + b"\x00\x00"
+    return b"E" + struct.pack(">I", len(body) + 4) + body
+
+
+
+
+def _log(event_type: str, severity: int = 6, **kwargs) -> None:
+    line = syslog_line(SERVICE_NAME, NODE_NAME, event_type, severity, **kwargs)
+    write_syslog_file(line)
+    forward_syslog(line, LOG_TARGET)
+
+
+class PostgresProtocol(asyncio.Protocol):
+    def __init__(self):
+        self._transport = None
+        self._peer = None
+        self._buf = b""
+        self._state = "startup"
+
+    def connection_made(self, transport):
+        self._transport = transport
+        self._peer = transport.get_extra_info("peername", ("?", 0))
+        _log("connect", src=self._peer[0], src_port=self._peer[1])
+
+    def data_received(self, data):
+        self._buf += data
+        self._process()
+
+    def _process(self):
+        if self._state == "startup":
+            if len(self._buf) < 4:
+                return
+            msg_len = struct.unpack(">I", self._buf[:4])[0]
+            if msg_len < 8 or msg_len > 10_000:
+                self._transport.close()
+                self._buf = b""
+                return
+            if len(self._buf) < msg_len:
+                return
+            msg = self._buf[:msg_len]
+            self._buf = self._buf[msg_len:]
+            self._handle_startup(msg)
+        elif self._state == "auth":
+            if len(self._buf) < 5:
+                return
+            msg_type = chr(self._buf[0])
+            msg_len = struct.unpack(">I", self._buf[1:5])[0]
+            if msg_len < 4 or msg_len > 10_000:
+                self._transport.close()
+                self._buf = b""
+                return
+            if len(self._buf) < msg_len + 1:
+                return
+            payload = self._buf[5:msg_len + 1]
+            self._buf = self._buf[msg_len + 1:]
+            if msg_type == "p":
+                self._handle_password(payload)
+
+    def _handle_startup(self, msg: bytes):
+        # Startup message: length(4) + protocol_version(4) + params (key=value\0 pairs)
+        if len(msg) < 8:
+            return
+        proto = struct.unpack(">I", msg[4:8])[0]
+        if proto == 80877103:  # SSL request
+            self._transport.write(b"N")  # reject SSL
+            return
+        params_raw = msg[8:].split(b"\x00")
+        params = {}
+        for i in range(0, len(params_raw) - 1, 2):
+            k = params_raw[i].decode(errors="replace")
+            v = params_raw[i + 1].decode(errors="replace") if i + 1 < len(params_raw) else ""
+            if k:
+                params[k] = v
+        username = params.get("user", "")
+        database = params.get("database", "")
+        _log("startup", src=self._peer[0], username=username, database=database)
+        self._state = "auth"
+        salt = os.urandom(4)
+        auth_md5 = b"R" + struct.pack(">I", 12) + struct.pack(">I", 5) + salt
+        self._transport.write(auth_md5)
+
+    def _handle_password(self, payload: bytes):
+        pw_hash = payload.rstrip(b"\x00").decode(errors="replace")
+        _log("auth", src=self._peer[0], pw_hash=pw_hash)
+        self._transport.write(_error_response("password authentication failed"))
+        self._transport.close()
+
+    def connection_lost(self, exc):
+        _log("disconnect", src=self._peer[0] if self._peer else "?")
+
+
+async def main():
+    _log("startup", msg=f"PostgreSQL server starting as {NODE_NAME}")
+    loop = asyncio.get_running_loop()
+    server = await loop.create_server(PostgresProtocol, "0.0.0.0", PORT)  # nosec B104
+    async with server:
+        await server.serve_forever()
+
+
+if __name__ == "__main__":
+    asyncio.run(main())

decnet/templates/postgres/syslog_bridge.py

@@ -0,0 +1,89 @@
+#!/usr/bin/env python3
+"""
+Shared RFC 5424 syslog helper used by service containers.
+
+Services call syslog_line() to format an RFC 5424 message, then
+write_syslog_file() to emit it to stdout — the container runtime
+captures it, and the host-side collector streams it into the log file.
+
+RFC 5424 structure:
+  <PRI>1 TIMESTAMP HOSTNAME APP-NAME PROCID MSGID [SD-ELEMENT] MSG
+
+Facility: local0 (16). SD element ID uses PEN 55555.
+"""
+
+from datetime import datetime, timezone
+from typing import Any
+
+# ─── Constants ────────────────────────────────────────────────────────────────
+
+_FACILITY_LOCAL0 = 16
+_SD_ID = "relay@55555"
+_NILVALUE = "-"
+
+SEVERITY_EMERG   = 0
+SEVERITY_ALERT   = 1
+SEVERITY_CRIT    = 2
+SEVERITY_ERROR   = 3
+SEVERITY_WARNING = 4
+SEVERITY_NOTICE  = 5
+SEVERITY_INFO    = 6
+SEVERITY_DEBUG   = 7
+
+_MAX_HOSTNAME = 255
+_MAX_APPNAME  = 48
+_MAX_MSGID    = 32
+
+# ─── Formatter ────────────────────────────────────────────────────────────────
+
+def _sd_escape(value: str) -> str:
+    """Escape SD-PARAM-VALUE per RFC 5424 §6.3.3."""
+    return value.replace("\\", "\\\\").replace('"', '\\"').replace("]", "\\]")
+
+
+def _sd_element(fields: dict[str, Any]) -> str:
+    if not fields:
+        return _NILVALUE
+    params = " ".join(f'{k}="{_sd_escape(str(v))}"' for k, v in fields.items())
+    return f"[{_SD_ID} {params}]"
+
+
+def syslog_line(
+    service: str,
+    hostname: str,
+    event_type: str,
+    severity: int = SEVERITY_INFO,
+    timestamp: datetime | None = None,
+    msg: str | None = None,
+    **fields: Any,
+) -> str:
+    """
+    Return a single RFC 5424-compliant syslog line (no trailing newline).
+
+    Args:
+        service:    APP-NAME (e.g. "http", "mysql")
+        hostname:   HOSTNAME (node name)
+        event_type: MSGID    (e.g. "request", "login_attempt")
+        severity:   Syslog severity integer (default: INFO=6)
+        timestamp:  UTC datetime; defaults to now
+        msg:        Optional free-text MSG
+        **fields:   Encoded as structured data params
+    """
+    pri     = f"<{_FACILITY_LOCAL0 * 8 + severity}>"
+    ts      = (timestamp or datetime.now(timezone.utc)).isoformat()
+    host    = (hostname or _NILVALUE)[:_MAX_HOSTNAME]
+    appname = (service  or _NILVALUE)[:_MAX_APPNAME]
+    msgid   = (event_type or _NILVALUE)[:_MAX_MSGID]
+    sd      = _sd_element(fields)
+    message = f" {msg}" if msg else ""
+    return f"{pri}1 {ts} {host} {appname} {_NILVALUE} {msgid} {sd}{message}"
+
+
+def write_syslog_file(line: str) -> None:
+    """Emit a syslog line to stdout for container log capture."""
+    print(line, flush=True)
+
+
+def forward_syslog(line: str, log_target: str) -> None:
+    """No-op stub. TCP forwarding is handled by rsyslog, not by service containers."""
+    pass