Add ROS2 message support #10538
Add ROS2 message support #10538
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Adds ROS2 message type support to the rclcpy module. Creating a Publisher now requires a ROS message type - all future messages must adhere to that message type. A small group of test messages are available in the std_msgs submodule of rclcpy, including Int32 and Bool. Message type detection is done through a type registry, and the appropriate C level information passed to the Micro-ROS interface. Ideally, future messages and message packages will be supported with an automated class and registry generator. Due to MicroROS restrictions, custom user message types cannot be supported without rebuilding Circuitpython. API changes: Removes the test publisher function `publish_int32` and replaces it with the correct `publish` function, which accepts a message object. Adds the MsgType parameter to publisher creation. Adds the std_msgs module to the module root.
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Hi - some suggestions. I will make this a draft PR for now, since you are going to do more. Also awaiting doc for several new constructors, etc. Otherwise it looks quite clean.
You could use mp_arg_parse_all_kw_array() even on the simple construtors, but maybe this is simpler and less code.
| static mp_obj_t bool_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) { | ||
| mp_arg_check_num(n_args, n_kw, 0, 1, true); | ||
| rclcpy_std_msgs_bool_obj_t *self = m_new_obj(rclcpy_std_msgs_bool_obj_t); | ||
| self->base.type = &rclcpy_std_msgs_bool_type; | ||
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| if (n_args == 1) { | ||
| self->data = mp_obj_is_true(args[0]); | ||
| } else { | ||
| self->data = false; | ||
| } | ||
| return MP_OBJ_FROM_PTR(self); | ||
| } | ||
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You can (and should) use the new mp_obj_malloc() or mp_obj_malloc_with_finaliser() (if you need a finaliser) instead of the old m_new_obj() and setting the base.type explicitly. Take a look at some other make_news in existing modules.
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Oh right, my bad. Was referencing old stuff from usermod for this bit.
| // This file is part of the CircuitPython project: https://circuitpython.org | ||
| // | ||
| // SPDX-FileCopyrightText: Copyright (c) 2025 Lucian Copeland | ||
| // | ||
| // SPDX-License-Identifier: MIT |
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Were these going to be omitted or moved to shared-module/?
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I figured I would post the "default" structure first before trying any shenanigans. I'll investigate the microcontroller/ResetReason example you mentioned to see if it's a better solution.
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I wanted to make sure the overall module and class structure looked acceptable, since I wasn't able to find other shared-bindings modules that attempt large class collections like this.
Adds ROS2 message type support to the rclcpy module. Creating a Publisher now requires a ROS message type - all future messages must adhere to that message type. A small group of simple test messages are available in the
std_msgssubmodule of rclcpy, including Int32 and Bool. Message type detection is done through a type registry, and the appropriate C level information passed to the Micro-ROS interface. Ideally, future messages and message packages will be supported with an automated class and registry generator. Due to MicroROS restrictions, custom user message types cannot be supported without rebuilding Circuitpython.Putting this up a little early to get eyes on my implementation of the registry and file arrangement while I work on updating the documentation and cleaning up formatting and translation checks. Tested for functionality with ROS2 Jazzy, and is working as expected.
Example:
API changes to
rclcpypublish_int32and replaces it with the correctpublishfunction, which accepts a message object.