fix(dc_bringup): auto-stage passthrough sink files before dc_bridge starts

The sim CI job on #471's migration failed: qrcodes_stdout reached every nav
waypoint but read zero QR codes. Root cause is a pre-existing but now much
more exposed gap -- every custom_config_files passthrough recipe (10 demos
after #471's migration, previously just the InfluxDB demo from #470) is
documented as a manual "mkdir -p ~/.dc && cp ... ~/.dc/" step before first
launch. Nothing runs that step automatically for a demo launched straight
from an installed package, so a fresh environment (CI, a new dev machine)
silently runs dc_bridge with no sink at all -- no crash, no error, just a
route nobody consumes.

dc_bringup.launch.py's build_bridge_and_mcap_actions already parses the
params file and rewrites custom_config_files at launch time for the
dc_mcap_writer case; extend the same OpaqueFunction to stage any
custom_config_files entry that's missing, copying it from the config/
directory CMakeLists installs as a sibling of params/. Never overwrites an
existing destination file, since elasticsearch.md and demos.md both
document hand-editing the staged copy to experiment.

Verified the staging logic in isolation (stages when missing, never
clobbers an existing/edited copy, no-ops when there's no matching source
file) and confirmed ruff/prek pass. The containerized deploy path
(deploy/robot/compose.isolated-network.yaml's bind mount) already covered
this correctly and is untouched.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WYVDzgJx2xLAzixNFm7b7H
Signed-off-by: David Bensoussan <d.bensoussan@proton.me>

Author: Minipada

dc_bringup/launch/dc_bringup.launch.py

@@ -2,6 +2,7 @@
 # SPDX-License-Identifier: MPL-2.0
 
 import os
+import shutil
 
 import yaml
 from ament_index_python.packages import get_package_prefix, get_package_share_directory
@@ -191,6 +192,36 @@ def _receives(destination_name):
     ]
 
 
+def _stage_custom_config_files(params_file_path, custom_config_files):
+    """Stage a demo's passthrough sink TOML(s) at the path `custom_config_files` names.
+
+    A `custom_config_files` entry (ADR-0003 passthrough, #471) is handed to `dc_bridge`
+    as a plain filesystem path -- nothing installs a file there on its own. A
+    containerized deploy solves this with a bind mount straight onto that path
+    (deploy/robot/compose.isolated-network.yaml); a demo launched from an installed
+    package has no such mount, so without this the referenced file is simply missing
+    and `dc_bridge` runs without the sink (see the sim CI job this fixed: qrcodes_stdout
+    reached every nav waypoint but read zero QR codes, because the passthrough console
+    sink was never in place, and no `dc.*` route makes it to the Measurement pipeline
+    without one). Recipes live in a `config/` directory `dc_demos/CMakeLists.txt`
+    installs as a sibling of `params/`, so that sibling is where this looks for a
+    same-named file to copy from. Never overwrites an existing destination file --
+    demos.md and elasticsearch.md both document hand-editing the staged copy to
+    experiment, which a blind refresh on every launch would clobber.
+    """
+    config_dir = os.path.join(
+        os.path.dirname(os.path.dirname(os.path.abspath(params_file_path))), "config"
+    )
+    for raw_path in custom_config_files:
+        dest_path = os.path.expanduser(os.path.expandvars(raw_path))
+        if os.path.exists(dest_path):
+            continue
+        candidate = os.path.join(config_dir, os.path.basename(dest_path))
+        if os.path.isfile(candidate):
+            os.makedirs(os.path.dirname(dest_path), exist_ok=True)
+            shutil.copyfile(candidate, dest_path)
+
+
 def build_bridge_and_mcap_actions(configured_params):
     """Build the `dc_bridge` Node, plus `dc_mcap_writer` if the params file enables it.
 
@@ -241,6 +272,11 @@ def _build(context, *args, **kwargs):
         except OSError:
             raw_params = {}
 
+        dc_bridge_params_early = (raw_params.get("dc_bridge") or {}).get("ros__parameters") or {}
+        _stage_custom_config_files(
+            params_file_path, dc_bridge_params_early.get("custom_config_files", [])
+        )
+
         mcap_params = (raw_params.get("dc_mcap_writer") or {}).get("ros__parameters") or {}
         bridge_parameters = [configured_params]
         extra_actions = []

dc_demos/params/elasticsearch.yaml

@@ -10,6 +10,9 @@ dc_bridge:
     # ADR-0003 passthrough: a raw Vector sink config listed in `custom_config_files`,
     # consuming the public `dc.<tag>` routes. Copy it into place before launching:
     #   mkdir -p ~/.dc && cp "$(ros2 pkg prefix dc_demos)/share/dc_demos/config/elasticsearch_sink.toml" ~/.dc/
+    # (dc_bringup.launch.py now stages this file automatically at launch time if
+    # it's not already there -- see _stage_custom_config_files -- so this manual
+    # step is only needed when running dc_bridge some other way.)
     #
     # `destinations` still has to name at least one blessed Destination, and the routes
     # the snippet consumes exist only for topics listed in *its* `inputs` — dc_bridge

dc_demos/params/fastdds_stats_pgsql_grafana.yaml

@@ -11,6 +11,9 @@ dc_bridge:
     # subscriptions and `dc.<tag>` routes from `destinations` alone, never from a
     # passthrough snippet's `inputs`. Copy the passthrough sink into place first:
     #   mkdir -p ~/.dc && cp "$(ros2 pkg prefix dc_demos)/share/dc_demos/config/fastdds_stats_pgsql_grafana_sink.toml" ~/.dc/
+    # (dc_bringup.launch.py now stages this file automatically at launch time if
+    # it's not already there -- see _stage_custom_config_files -- so this manual
+    # step is only needed when running dc_bridge some other way.)
     destinations: ["records_log"]
     records_log:
       type: file

dc_demos/params/group_memory_uptime_stdout.yaml

@@ -11,6 +11,9 @@ dc_bridge:
     # subscriptions and `dc.<tag>` routes from `destinations` alone, never from a
     # passthrough snippet's `inputs`. Copy the passthrough sink into place first:
     #   mkdir -p ~/.dc && cp "$(ros2 pkg prefix dc_demos)/share/dc_demos/config/group_memory_uptime_stdout_sink.toml" ~/.dc/
+    # (dc_bringup.launch.py now stages this file automatically at launch time if
+    # it's not already there -- see _stage_custom_config_files -- so this manual
+    # step is only needed when running dc_bridge some other way.)
     destinations: ["records_log"]
     records_log:
       type: file

dc_demos/params/qrcodes_minio_pgsql.yaml

@@ -23,6 +23,9 @@ dc_bridge:
     #
     # Copy the passthrough sink into place first:
     #   mkdir -p ~/.dc && cp "$(ros2 pkg prefix dc_demos)/share/dc_demos/config/qrcodes_minio_pgsql_sink.toml" ~/.dc/
+    # (dc_bringup.launch.py now stages this file automatically at launch time if
+    # it's not already there -- see _stage_custom_config_files -- so this manual
+    # step is only needed when running dc_bridge some other way.)
     destinations: ["records_log", "rustfs"]
     records_log:
       type: file

dc_demos/params/qrcodes_stdout.yaml

@@ -11,6 +11,9 @@ dc_bridge:
     # subscriptions and `dc.<tag>` routes from `destinations` alone, never from a
     # passthrough snippet's `inputs`. Copy the passthrough sink into place first:
     #   mkdir -p ~/.dc && cp "$(ros2 pkg prefix dc_demos)/share/dc_demos/config/qrcodes_stdout_sink.toml" ~/.dc/
+    # (dc_bringup.launch.py now stages this file automatically at launch time if
+    # it's not already there -- see _stage_custom_config_files -- so this manual
+    # step is only needed when running dc_bridge some other way.)
     destinations: ["records_log"]
     records_log:
       type: file

dc_demos/params/tb3_simulation_influxdb.yaml

@@ -12,6 +12,9 @@ dc_bridge:
     # doc/src/dc/destinations.md. Copy the example sink shipped with this package into
     # place before launching this demo:
     #   mkdir -p ~/.dc && cp "$(ros2 pkg prefix dc_demos)/share/dc_demos/config/tb3_simulation_influxdb_sink.toml" ~/.dc/
+    # (dc_bringup.launch.py now stages this file automatically at launch time if
+    # it's not already there -- see _stage_custom_config_files -- so this manual
+    # step is only needed when running dc_bridge some other way.)
     #
     # `destinations` must still name at least one *blessed* Destination, and its `inputs`
     # are what create the `dc.<tag>` routes the snippet consumes — dc_bridge derives both

dc_demos/params/tb3_simulation_pgsql_minio.yaml

@@ -23,6 +23,9 @@ dc_bridge:
     #
     # Copy the passthrough sink into place first:
     #   mkdir -p ~/.dc && cp "$(ros2 pkg prefix dc_demos)/share/dc_demos/config/tb3_simulation_pgsql_minio_sink.toml" ~/.dc/
+    # (dc_bringup.launch.py now stages this file automatically at launch time if
+    # it's not already there -- see _stage_custom_config_files -- so this manual
+    # step is only needed when running dc_bridge some other way.)
     destinations: ["records_log", "rustfs"]
     records_log:
       type: file

dc_demos/params/tb3_simulation_stdout.yaml

@@ -11,6 +11,9 @@ dc_bridge:
     # subscriptions and `dc.<tag>` routes from `destinations` alone, never from a
     # passthrough snippet's `inputs`. Copy the passthrough sink into place first:
     #   mkdir -p ~/.dc && cp "$(ros2 pkg prefix dc_demos)/share/dc_demos/config/tb3_simulation_stdout_sink.toml" ~/.dc/
+    # (dc_bringup.launch.py now stages this file automatically at launch time if
+    # it's not already there -- see _stage_custom_config_files -- so this manual
+    # step is only needed when running dc_bridge some other way.)
     destinations: ["records_log"]
     records_log:
       type: file

dc_demos/params/uptime_custom_stdout.yaml

@@ -11,6 +11,9 @@ dc_bridge:
     # subscriptions and `dc.<tag>` routes from `destinations` alone, never from a
     # passthrough snippet's `inputs`. Copy the passthrough sink into place first:
     #   mkdir -p ~/.dc && cp "$(ros2 pkg prefix dc_demos)/share/dc_demos/config/uptime_custom_stdout_sink.toml" ~/.dc/
+    # (dc_bringup.launch.py now stages this file automatically at launch time if
+    # it's not already there -- see _stage_custom_config_files -- so this manual
+    # step is only needed when running dc_bridge some other way.)
     destinations: ["records_log"]
     records_log:
       type: file