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/mongodb/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 27017
+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/mongodb/entrypoint.sh

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

decnet/templates/mongodb/server.py

@@ -0,0 +1,127 @@
+#!/usr/bin/env python3
+"""
+MongoDBserver.
+Implements the MongoDB wire protocol OP_MSG/OP_QUERY handshake. Responds
+to isMaster/hello, listDatabases, and authenticate commands. Logs all
+received messages 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", "mongodb")
+SERVICE_NAME   = "mongodb"
+LOG_TARGET = os.environ.get("LOG_TARGET", "")
+PORT = int(os.environ.get("PORT", "27017"))
+
+# Minimal BSON helpers
+def _bson_str(key: str, val: str) -> bytes:
+    k = key.encode() + b"\x00"
+    v = val.encode() + b"\x00"
+    return b"\x02" + k + struct.pack("<I", len(v)) + v
+
+def _bson_int32(key: str, val: int) -> bytes:
+    return b"\x10" + key.encode() + b"\x00" + struct.pack("<i", val)
+
+def _bson_bool(key: str, val: bool) -> bytes:
+    return b"\x08" + key.encode() + b"\x00" + (b"\x01" if val else b"\x00")
+
+def _bson_doc(*fields: bytes) -> bytes:
+    body = b"".join(fields) + b"\x00"
+    return struct.pack("<I", len(body) + 4) + body
+
+def _op_reply(request_id: int, doc: bytes) -> bytes:
+    # OP_REPLY header: total_len(4), req_id(4), response_to(4), opcode(4)=1,
+    #                  flags(4), cursor_id(8), starting_from(4), number_returned(4), docs
+    header = struct.pack(
+        "<iiiiiqii",
+        16 + 20 + len(doc),  # total length
+        0,                    # request id
+        request_id,           # response to
+        1,                    # OP_REPLY
+        0,                    # flags
+        0,                    # cursor id (int64)
+        0,                    # starting from
+        1,                    # number returned
+    )
+    return header + doc
+
+def _op_msg(request_id: int, doc: bytes) -> bytes:
+    payload = b"\x00" + doc
+    flag_bits = struct.pack("<I", 0)
+    msg_body = flag_bits + payload
+    header = struct.pack("<iiii",
+        16 + len(msg_body),
+        1,
+        request_id,
+        2013,
+    )
+    return header + msg_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 MongoDBProtocol(asyncio.Protocol):
+    def __init__(self):
+        self._transport = None
+        self._peer = None
+        self._buf = b""
+
+    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
+        while len(self._buf) >= 16:
+            msg_len = struct.unpack("<I", self._buf[:4])[0]
+            if msg_len < 16 or msg_len > 48 * 1024 * 1024:
+                self._transport.close()
+                self._buf = b""
+                return
+            if len(self._buf) < msg_len:
+                break
+            msg = self._buf[:msg_len]
+            self._buf = self._buf[msg_len:]
+            self._handle_message(msg)
+
+    def _handle_message(self, msg: bytes):
+        if len(msg) < 16:
+            return
+        request_id = struct.unpack("<I", msg[4:8])[0]
+        opcode = struct.unpack("<I", msg[12:16])[0]
+        _log("message", src=self._peer[0], opcode=opcode, length=len(msg))
+
+        # Build a generic isMaster-style OK response
+        reply_doc = _bson_doc(
+            _bson_bool("ismaster", True),
+            _bson_int32("maxWireVersion", 17),
+            _bson_int32("minWireVersion", 0),
+            _bson_str("version", "6.0.5"),
+            _bson_int32("ok", 1),
+        )
+        if opcode == 2013:  # OP_MSG
+            self._transport.write(_op_msg(request_id, reply_doc))
+        else:
+            self._transport.write(_op_reply(request_id, reply_doc))
+
+    def connection_lost(self, exc):
+        _log("disconnect", src=self._peer[0] if self._peer else "?")
+
+
+async def main():
+    _log("startup", msg=f"MongoDB server starting as {NODE_NAME}")
+    loop = asyncio.get_running_loop()
+    server = await loop.create_server(MongoDBProtocol, "0.0.0.0", PORT)  # nosec B104
+    async with server:
+        await server.serve_forever()
+
+
+if __name__ == "__main__":
+    asyncio.run(main())

decnet/templates/mongodb/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