apoorva/greenhouse
2
1
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Add 'rosbags/' from commit 'c80625df279c154c6ec069cbac30faa319755e47'

Browse Source 
git-subtree-dir: rosbags
git-subtree-mainline: 48df1fbdf4
git-subtree-split: c80625df27
This commit is contained in:
Apoorva Gupta
2023-03-28 18:21:08 +05:30
parent 48df1fbdf4 c80625df27
commit 0c9504b343
99 changed files with 16378 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files
rosbags/docs/topics/convert.rst
+36
View File
@@ -0,0 +1,36 @@
Convert rosbag versions
=======================
The :py:mod:`rosbags.convert` package includes a CLI tool to convert legacy rosbag1 files to rosbag2 and vice versa.
Features
--------
- Reasonably fast, as it converts raw ROS1 messages to raw CDR messages without going though deserialization and serialization
- Tries to match ROS1 message type names to registered ROS2 types
- Automatically registers unknown message types present in the legacy rosbag file for the conversion
- Handles differences of ``std_msgs/msg/Header`` between both ROS versions
Limitations
-----------
- Refuses to convert unindexed rosbag1 files, please reindex files before conversion
- Currently does not handle split bags
- Only ROS2 default message types are supported when converting rosbag2 to rosbag1
Usage
-----
.. code-block:: console
# Convert "foo.bag", result will be "foo/"
$ rosbags-convert foo.bag
# Convert "bar", result will be "bar.bag"
$ rosbags-convert bar
# Convert "foo.bag", save the result as "bar"
$ rosbags-convert foo.bag --dst /path/to/bar
# Convert "bar", save the result as "foo.bag"
$ rosbags-convert bar --dst /path/to/foo.bag
rosbags/docs/topics/highlevel.rst
+22
View File
@@ -0,0 +1,22 @@
Highlevel APIs
==============
The :py:mod:`rosbags.highlevel` package provides classes that abstract the complexity of ROS types, serialization and message access into single easy-to-use interfaces.
All in one reader
-----------------
Instances of the :py:class:`AnyReader <rosbags.highlevel.AnyReader>` class give unified access to ROS1 and ROS2 bag files. If a bag file includes message definitions the reader auto-registers all messages into a blank type store, otherwise it falls back to the default type store. It also exposes appropriate deserialization methods on the reader instance itself.
.. code-block:: python
from pathlib import Path
from rosbags.highlevel import AnyReader
# create reader instance and open for reading
with AnyReader([Path('/home/ros/rosbag_2020_03_24')]) as reader:
connections = [x for x in reader.connections if x.topic == '/imu_raw/Imu']
for connection, timestamp, rawdata in reader.messages(connections=connections):
msg = reader.deserialize(rawdata, connection.msgtype)
print(msg.header.frame_id)
AnyReader takes a list of ``pathlib.Path`` instances as arguments. It can take either one ROS2 bag file or one or more ROS1 bag files belonging to a split bag. The reader will replay ROS1 split bags in correct timestamp order.
rosbags/docs/topics/rosbag1.rst
+54
View File
@@ -0,0 +1,54 @@
Rosbag1
=======
The :py:mod:`rosbags.rosbag1` package provides fast read-only access to raw messages stored in the legacy bag format. The rosbag1 support is built for a ROS2 world and some APIs and values perform normalizations to mimic ROS2 behavior and make messages originating from rosbag1 and rosbag2 behave identically. Most notably message types are internally renamed to match their ROS2 counterparts.
Writing rosbag1
---------------
Instances of the :py:class:`Writer <rosbags.rosbag1.Writer>` class can create and write to new rosbag1 files. It is usually used as a context manager. Before the first message of a topic can be written, its topic must first be added to the bag. The following example shows the typical usage pattern:
.. code-block:: python
from rosbags.rosbag1 import Writer
from rosbags.serde import cdr_to_ros1, serialize_cdr
from rosbags.typesys.types import std_msgs__msg__String as String
# create writer instance and open for writing
with Writer('/home/ros/rosbag_2020_03_24.bag') as writer:
# add new connection
topic = '/chatter'
msgtype = String.__msgtype__
connection = writer.add_connection(topic, msgtype, latching=True)
# serialize and write message
message = String('hello world')
timestamp = 42
writer.write(connection, timestamp, cdr_to_ros1(serialize_cdr(message, msgtype), msgtype))
Reading rosbag1
---------------
Instances of the :py:class:`Reader <rosbags.rosbag2.Reader>` class are typically used as context managers and provide access to bag metadata and contents after the bag has been opened. The following example shows the typical usage pattern:
.. code-block:: python
from rosbags.rosbag1 import Reader
from rosbags.serde import deserialize_cdr, ros1_to_cdr
# create reader instance
with Reader('/home/ros/rosbag_2020_03_24.bag') as reader:
# topic and msgtype information is available on .connections list
for connection in reader.connections:
print(connection.topic, connection.msgtype)
# iterate over messages
for connection, timestamp, rawdata in reader.messages():
if connection.topic == '/imu_raw/Imu':
msg = deserialize_cdr(ros1_to_cdr(rawdata, connection.msgtype), connection.msgtype)
print(msg.header.frame_id)
# messages() accepts connection filters
connections = [x for x in reader.connections if x.topic == '/imu_raw/Imu']
for connection, timestamp, rawdata in reader.messages(connections=connections):
msg = deserialize_cdr(ros1_to_cdr(rawdata, connection.msgtype), connection.msgtype)
print(msg.header.frame_id)
rosbags/docs/topics/rosbag2.rst
+70
View File
@@ -0,0 +1,70 @@
Rosbag2
=======
The :py:mod:`rosbags.rosbag2` package provides a conformant implementation of rosbag2. It provides read-write access to raw message data saved inside rosbag2 containers, and supports all features present in the C++ reference implementation.
Supported Versions
------------------
All versions up to the current (ROS2 Humble) version 6 are supported.
Supported Features
------------------
Rosbag2 is a flexible format that supports plugging different serialization methods, compression formats, and storage containers together. The rosbag2 C++ reference implementation is build around plugins that provide serialization, compression, and storage. This project implements all rosbag2 core plugins that are distributed with the C++ reference implementation.
:Serializers:
- cdr (without wstring)
:Compressors:
- zstd
:Storages:
- sqlite3
- mcap
Writing rosbag2
---------------
Instances of the :py:class:`Writer <rosbags.rosbag2.Writer>` class can create and write to new rosbag2 files. It is usually used as a context manager. Before the first message of a topic can be written, its topic must first be added to the bag. The following example shows the typical usage pattern:
.. code-block:: python
from rosbags.rosbag2 import Writer
from rosbags.serde import serialize_cdr
from rosbags.typesys.types import std_msgs__msg__String as String
# create writer instance and open for writing
with Writer('/home/ros/rosbag_2020_03_24') as writer:
# add new connection
topic = '/chatter'
msgtype = String.__msgtype__
connection = writer.add_connection(topic, msgtype, 'cdr', '')
# serialize and write message
timestamp = 42
message = String('hello world')
writer.write(connection, timestamp, serialize_cdr(message, msgtype))
Reading rosbag2
---------------
Instances of the :py:class:`Reader <rosbags.rosbag2.Reader>` class are used to read rosbag2 metadata and its contents. Most of the metadata is available on Reader instances right away, messages can only be accessed after the bag has been opened. To this end it is recommended to use the Reader as a context manager. The following example shows the typical usage pattern:
.. code-block:: python
from rosbags.rosbag2 import Reader
from rosbags.serde import deserialize_cdr
# create reader instance and open for reading
with Reader('/home/ros/rosbag_2020_03_24') as reader:
# topic and msgtype information is available on .connections list
for connection in reader.connections:
print(connection.topic, connection.msgtype)
# iterate over messages
for connection, timestamp, rawdata in reader.messages():
if connection.topic == '/imu_raw/Imu':
msg = deserialize_cdr(rawdata, connection.msgtype)
print(msg.header.frame_id)
# messages() accepts connection filters
connections = [x for x in reader.connections if x.topic == '/imu_raw/Imu']
for connection, timestamp, rawdata in reader.messages(connections=connections):
msg = deserialize_cdr(rawdata, connection.msgtype)
print(msg.header.frame_id)
rosbags/docs/topics/serde.rst
+49
View File
@@ -0,0 +1,49 @@
Serialization and deserialization
=================================
The serialization and deserialization system :py:mod:`rosbags.serde` supports multiple raw message formats. For each format it provides a pair of functions, one for serialization and one for deserialization. In addition to the data to process each function usually only requires the message type name.
Deserialization
---------------
Deserialize a CDR bytes object using :py:func:`deserialize_cdr() <rosbags.serde.deserialize_cdr>`:
.. code-block:: python
from rosbags.serde import deserialize_cdr
# rawdata is of type bytes and contains serialized message
msg = deserialize_cdr(rawdata, 'geometry_msgs/msg/Quaternion')
Deserialize a ROS1 bytes object using :py:func:`deserialize_ros1() <rosbags.serde.deserialize_ros1>`:
.. code-block:: python
from rosbags.serde import deserialize_ros1
# rawdata is of type bytes and contains serialized message
msg = deserialize_ros1(rawdata, 'geometry_msgs/msg/Quaternion')
Serialization
---------------
Serialize a message with CDR using :py:func:`serialize_cdr() <rosbags.serde.serialize_cdr>`:
.. code-block:: python
from rosbags.serde import serialize_cdr
# serialize message with system endianess
serialized = serialize_cdr(msg, 'geometry_msgs/msg/Quaternion')
# serialize message with explicit endianess
serialized = serialize_cdr(msg, 'geometry_msgs/msg/Quaternion', little_endian=False)
Serialize a message with ROS1 using :py:func:`serialize_ros1() <rosbags.serde.serialize_ros1>`:
.. code-block:: python
from rosbags.serde import serialize_ros1
serialized = serialize_ros1(msg, 'geometry_msgs/msg/Quaternion')
rosbags/docs/topics/typesys-types.rst
+194
View File
@@ -0,0 +1,194 @@
builtin_interfaces
******************
- :py:class:`Duration <rosbags.typesys.types.builtin_interfaces__msg__Duration>`
- :py:class:`Time <rosbags.typesys.types.builtin_interfaces__msg__Time>`
diagnostic_msgs
***************
- :py:class:`DiagnosticArray <rosbags.typesys.types.diagnostic_msgs__msg__DiagnosticArray>`
- :py:class:`DiagnosticStatus <rosbags.typesys.types.diagnostic_msgs__msg__DiagnosticStatus>`
- :py:class:`KeyValue <rosbags.typesys.types.diagnostic_msgs__msg__KeyValue>`
geometry_msgs
*************
- :py:class:`Accel <rosbags.typesys.types.geometry_msgs__msg__Accel>`
- :py:class:`AccelStamped <rosbags.typesys.types.geometry_msgs__msg__AccelStamped>`
- :py:class:`AccelWithCovariance <rosbags.typesys.types.geometry_msgs__msg__AccelWithCovariance>`
- :py:class:`AccelWithCovarianceStamped <rosbags.typesys.types.geometry_msgs__msg__AccelWithCovarianceStamped>`
- :py:class:`Inertia <rosbags.typesys.types.geometry_msgs__msg__Inertia>`
- :py:class:`InertiaStamped <rosbags.typesys.types.geometry_msgs__msg__InertiaStamped>`
- :py:class:`Point <rosbags.typesys.types.geometry_msgs__msg__Point>`
- :py:class:`Point32 <rosbags.typesys.types.geometry_msgs__msg__Point32>`
- :py:class:`PointStamped <rosbags.typesys.types.geometry_msgs__msg__PointStamped>`
- :py:class:`Polygon <rosbags.typesys.types.geometry_msgs__msg__Polygon>`
- :py:class:`PolygonStamped <rosbags.typesys.types.geometry_msgs__msg__PolygonStamped>`
- :py:class:`Pose <rosbags.typesys.types.geometry_msgs__msg__Pose>`
- :py:class:`Pose2D <rosbags.typesys.types.geometry_msgs__msg__Pose2D>`
- :py:class:`PoseArray <rosbags.typesys.types.geometry_msgs__msg__PoseArray>`
- :py:class:`PoseStamped <rosbags.typesys.types.geometry_msgs__msg__PoseStamped>`
- :py:class:`PoseWithCovariance <rosbags.typesys.types.geometry_msgs__msg__PoseWithCovariance>`
- :py:class:`PoseWithCovarianceStamped <rosbags.typesys.types.geometry_msgs__msg__PoseWithCovarianceStamped>`
- :py:class:`Quaternion <rosbags.typesys.types.geometry_msgs__msg__Quaternion>`
- :py:class:`QuaternionStamped <rosbags.typesys.types.geometry_msgs__msg__QuaternionStamped>`
- :py:class:`Transform <rosbags.typesys.types.geometry_msgs__msg__Transform>`
- :py:class:`TransformStamped <rosbags.typesys.types.geometry_msgs__msg__TransformStamped>`
- :py:class:`Twist <rosbags.typesys.types.geometry_msgs__msg__Twist>`
- :py:class:`TwistStamped <rosbags.typesys.types.geometry_msgs__msg__TwistStamped>`
- :py:class:`TwistWithCovariance <rosbags.typesys.types.geometry_msgs__msg__TwistWithCovariance>`
- :py:class:`TwistWithCovarianceStamped <rosbags.typesys.types.geometry_msgs__msg__TwistWithCovarianceStamped>`
- :py:class:`Vector3 <rosbags.typesys.types.geometry_msgs__msg__Vector3>`
- :py:class:`Vector3Stamped <rosbags.typesys.types.geometry_msgs__msg__Vector3Stamped>`
- :py:class:`Wrench <rosbags.typesys.types.geometry_msgs__msg__Wrench>`
- :py:class:`WrenchStamped <rosbags.typesys.types.geometry_msgs__msg__WrenchStamped>`
libstatistics_collector
***********************
- :py:class:`DummyMessage <rosbags.typesys.types.libstatistics_collector__msg__DummyMessage>`
lifecycle_msgs
**************
- :py:class:`State <rosbags.typesys.types.lifecycle_msgs__msg__State>`
- :py:class:`Transition <rosbags.typesys.types.lifecycle_msgs__msg__Transition>`
- :py:class:`TransitionDescription <rosbags.typesys.types.lifecycle_msgs__msg__TransitionDescription>`
- :py:class:`TransitionEvent <rosbags.typesys.types.lifecycle_msgs__msg__TransitionEvent>`
nav_msgs
********
- :py:class:`GridCells <rosbags.typesys.types.nav_msgs__msg__GridCells>`
- :py:class:`MapMetaData <rosbags.typesys.types.nav_msgs__msg__MapMetaData>`
- :py:class:`OccupancyGrid <rosbags.typesys.types.nav_msgs__msg__OccupancyGrid>`
- :py:class:`Odometry <rosbags.typesys.types.nav_msgs__msg__Odometry>`
- :py:class:`Path <rosbags.typesys.types.nav_msgs__msg__Path>`
rcl_interfaces
**************
- :py:class:`FloatingPointRange <rosbags.typesys.types.rcl_interfaces__msg__FloatingPointRange>`
- :py:class:`IntegerRange <rosbags.typesys.types.rcl_interfaces__msg__IntegerRange>`
- :py:class:`ListParametersResult <rosbags.typesys.types.rcl_interfaces__msg__ListParametersResult>`
- :py:class:`Log <rosbags.typesys.types.rcl_interfaces__msg__Log>`
- :py:class:`Parameter <rosbags.typesys.types.rcl_interfaces__msg__Parameter>`
- :py:class:`ParameterDescriptor <rosbags.typesys.types.rcl_interfaces__msg__ParameterDescriptor>`
- :py:class:`ParameterEvent <rosbags.typesys.types.rcl_interfaces__msg__ParameterEvent>`
- :py:class:`ParameterEventDescriptors <rosbags.typesys.types.rcl_interfaces__msg__ParameterEventDescriptors>`
- :py:class:`ParameterType <rosbags.typesys.types.rcl_interfaces__msg__ParameterType>`
- :py:class:`ParameterValue <rosbags.typesys.types.rcl_interfaces__msg__ParameterValue>`
- :py:class:`SetParametersResult <rosbags.typesys.types.rcl_interfaces__msg__SetParametersResult>`
rmw_dds_common
**************
- :py:class:`Gid <rosbags.typesys.types.rmw_dds_common__msg__Gid>`
- :py:class:`NodeEntitiesInfo <rosbags.typesys.types.rmw_dds_common__msg__NodeEntitiesInfo>`
- :py:class:`ParticipantEntitiesInfo <rosbags.typesys.types.rmw_dds_common__msg__ParticipantEntitiesInfo>`
rosgraph_msgs
*************
- :py:class:`Clock <rosbags.typesys.types.rosgraph_msgs__msg__Clock>`
sensor_msgs
***********
- :py:class:`BatteryState <rosbags.typesys.types.sensor_msgs__msg__BatteryState>`
- :py:class:`CameraInfo <rosbags.typesys.types.sensor_msgs__msg__CameraInfo>`
- :py:class:`ChannelFloat32 <rosbags.typesys.types.sensor_msgs__msg__ChannelFloat32>`
- :py:class:`CompressedImage <rosbags.typesys.types.sensor_msgs__msg__CompressedImage>`
- :py:class:`FluidPressure <rosbags.typesys.types.sensor_msgs__msg__FluidPressure>`
- :py:class:`Illuminance <rosbags.typesys.types.sensor_msgs__msg__Illuminance>`
- :py:class:`Image <rosbags.typesys.types.sensor_msgs__msg__Image>`
- :py:class:`Imu <rosbags.typesys.types.sensor_msgs__msg__Imu>`
- :py:class:`JointState <rosbags.typesys.types.sensor_msgs__msg__JointState>`
- :py:class:`Joy <rosbags.typesys.types.sensor_msgs__msg__Joy>`
- :py:class:`JoyFeedback <rosbags.typesys.types.sensor_msgs__msg__JoyFeedback>`
- :py:class:`JoyFeedbackArray <rosbags.typesys.types.sensor_msgs__msg__JoyFeedbackArray>`
- :py:class:`LaserEcho <rosbags.typesys.types.sensor_msgs__msg__LaserEcho>`
- :py:class:`LaserScan <rosbags.typesys.types.sensor_msgs__msg__LaserScan>`
- :py:class:`MagneticField <rosbags.typesys.types.sensor_msgs__msg__MagneticField>`
- :py:class:`MultiDOFJointState <rosbags.typesys.types.sensor_msgs__msg__MultiDOFJointState>`
- :py:class:`MultiEchoLaserScan <rosbags.typesys.types.sensor_msgs__msg__MultiEchoLaserScan>`
- :py:class:`NavSatFix <rosbags.typesys.types.sensor_msgs__msg__NavSatFix>`
- :py:class:`NavSatStatus <rosbags.typesys.types.sensor_msgs__msg__NavSatStatus>`
- :py:class:`PointCloud <rosbags.typesys.types.sensor_msgs__msg__PointCloud>`
- :py:class:`PointCloud2 <rosbags.typesys.types.sensor_msgs__msg__PointCloud2>`
- :py:class:`PointField <rosbags.typesys.types.sensor_msgs__msg__PointField>`
- :py:class:`Range <rosbags.typesys.types.sensor_msgs__msg__Range>`
- :py:class:`RegionOfInterest <rosbags.typesys.types.sensor_msgs__msg__RegionOfInterest>`
- :py:class:`RelativeHumidity <rosbags.typesys.types.sensor_msgs__msg__RelativeHumidity>`
- :py:class:`Temperature <rosbags.typesys.types.sensor_msgs__msg__Temperature>`
- :py:class:`TimeReference <rosbags.typesys.types.sensor_msgs__msg__TimeReference>`
shape_msgs
**********
- :py:class:`Mesh <rosbags.typesys.types.shape_msgs__msg__Mesh>`
- :py:class:`MeshTriangle <rosbags.typesys.types.shape_msgs__msg__MeshTriangle>`
- :py:class:`Plane <rosbags.typesys.types.shape_msgs__msg__Plane>`
- :py:class:`SolidPrimitive <rosbags.typesys.types.shape_msgs__msg__SolidPrimitive>`
statistics_msgs
***************
- :py:class:`MetricsMessage <rosbags.typesys.types.statistics_msgs__msg__MetricsMessage>`
- :py:class:`StatisticDataPoint <rosbags.typesys.types.statistics_msgs__msg__StatisticDataPoint>`
- :py:class:`StatisticDataType <rosbags.typesys.types.statistics_msgs__msg__StatisticDataType>`
std_msgs
********
- :py:class:`Bool <rosbags.typesys.types.std_msgs__msg__Bool>`
- :py:class:`Byte <rosbags.typesys.types.std_msgs__msg__Byte>`
- :py:class:`ByteMultiArray <rosbags.typesys.types.std_msgs__msg__ByteMultiArray>`
- :py:class:`Char <rosbags.typesys.types.std_msgs__msg__Char>`
- :py:class:`ColorRGBA <rosbags.typesys.types.std_msgs__msg__ColorRGBA>`
- :py:class:`Empty <rosbags.typesys.types.std_msgs__msg__Empty>`
- :py:class:`Float32 <rosbags.typesys.types.std_msgs__msg__Float32>`
- :py:class:`Float32MultiArray <rosbags.typesys.types.std_msgs__msg__Float32MultiArray>`
- :py:class:`Float64 <rosbags.typesys.types.std_msgs__msg__Float64>`
- :py:class:`Float64MultiArray <rosbags.typesys.types.std_msgs__msg__Float64MultiArray>`
- :py:class:`Header <rosbags.typesys.types.std_msgs__msg__Header>`
- :py:class:`Int16 <rosbags.typesys.types.std_msgs__msg__Int16>`
- :py:class:`Int16MultiArray <rosbags.typesys.types.std_msgs__msg__Int16MultiArray>`
- :py:class:`Int32 <rosbags.typesys.types.std_msgs__msg__Int32>`
- :py:class:`Int32MultiArray <rosbags.typesys.types.std_msgs__msg__Int32MultiArray>`
- :py:class:`Int64 <rosbags.typesys.types.std_msgs__msg__Int64>`
- :py:class:`Int64MultiArray <rosbags.typesys.types.std_msgs__msg__Int64MultiArray>`
- :py:class:`Int8 <rosbags.typesys.types.std_msgs__msg__Int8>`
- :py:class:`Int8MultiArray <rosbags.typesys.types.std_msgs__msg__Int8MultiArray>`
- :py:class:`MultiArrayDimension <rosbags.typesys.types.std_msgs__msg__MultiArrayDimension>`
- :py:class:`MultiArrayLayout <rosbags.typesys.types.std_msgs__msg__MultiArrayLayout>`
- :py:class:`String <rosbags.typesys.types.std_msgs__msg__String>`
- :py:class:`UInt16 <rosbags.typesys.types.std_msgs__msg__UInt16>`
- :py:class:`UInt16MultiArray <rosbags.typesys.types.std_msgs__msg__UInt16MultiArray>`
- :py:class:`UInt32 <rosbags.typesys.types.std_msgs__msg__UInt32>`
- :py:class:`UInt32MultiArray <rosbags.typesys.types.std_msgs__msg__UInt32MultiArray>`
- :py:class:`UInt64 <rosbags.typesys.types.std_msgs__msg__UInt64>`
- :py:class:`UInt64MultiArray <rosbags.typesys.types.std_msgs__msg__UInt64MultiArray>`
- :py:class:`UInt8 <rosbags.typesys.types.std_msgs__msg__UInt8>`
- :py:class:`UInt8MultiArray <rosbags.typesys.types.std_msgs__msg__UInt8MultiArray>`
stereo_msgs
***********
- :py:class:`DisparityImage <rosbags.typesys.types.stereo_msgs__msg__DisparityImage>`
tf2_msgs
********
- :py:class:`TF2Error <rosbags.typesys.types.tf2_msgs__msg__TF2Error>`
- :py:class:`TFMessage <rosbags.typesys.types.tf2_msgs__msg__TFMessage>`
trajectory_msgs
***************
- :py:class:`JointTrajectory <rosbags.typesys.types.trajectory_msgs__msg__JointTrajectory>`
- :py:class:`JointTrajectoryPoint <rosbags.typesys.types.trajectory_msgs__msg__JointTrajectoryPoint>`
- :py:class:`MultiDOFJointTrajectory <rosbags.typesys.types.trajectory_msgs__msg__MultiDOFJointTrajectory>`
- :py:class:`MultiDOFJointTrajectoryPoint <rosbags.typesys.types.trajectory_msgs__msg__MultiDOFJointTrajectoryPoint>`
unique_identifier_msgs
**********************
- :py:class:`UUID <rosbags.typesys.types.unique_identifier_msgs__msg__UUID>`
visualization_msgs
******************
- :py:class:`ImageMarker <rosbags.typesys.types.visualization_msgs__msg__ImageMarker>`
- :py:class:`InteractiveMarker <rosbags.typesys.types.visualization_msgs__msg__InteractiveMarker>`
- :py:class:`InteractiveMarkerControl <rosbags.typesys.types.visualization_msgs__msg__InteractiveMarkerControl>`
- :py:class:`InteractiveMarkerFeedback <rosbags.typesys.types.visualization_msgs__msg__InteractiveMarkerFeedback>`
- :py:class:`InteractiveMarkerInit <rosbags.typesys.types.visualization_msgs__msg__InteractiveMarkerInit>`
- :py:class:`InteractiveMarkerPose <rosbags.typesys.types.visualization_msgs__msg__InteractiveMarkerPose>`
- :py:class:`InteractiveMarkerUpdate <rosbags.typesys.types.visualization_msgs__msg__InteractiveMarkerUpdate>`
- :py:class:`Marker <rosbags.typesys.types.visualization_msgs__msg__Marker>`
- :py:class:`MarkerArray <rosbags.typesys.types.visualization_msgs__msg__MarkerArray>`
- :py:class:`MenuEntry <rosbags.typesys.types.visualization_msgs__msg__MenuEntry>`
rosbags/docs/topics/typesys.rst
+44
View File
@@ -0,0 +1,44 @@
Type system
===========
Rosbags ships its own pure python typesystem :py:mod:`rosbags.typesys`. It uses parse trees to represent message definitions internally. It ships its own ``.idl`` and ``.msg`` definition parser to convert message definition files into the internal format.
Out of the box it supports the message types defined by the standard ROS2 distribution. Message types can be parsed and added on the fly during runtime without an additional build step.
Message instances
-----------------
The type system generates a dataclass for each message type. These dataclasses give direct read write access to all mutable fields of a message. Fields should be mutated with care as no type checking is applied during runtime.
.. note::
Limitation: While the type system parses message definitions with array bounds and/or default values, neither bounds nor default values are enforced or assigned to message instances.
Included message types
----------------------
.. include:: ./typesys-types.rst
Extending the type system
-------------------------
Adding custom message types consists of two steps. First, message definitions are converted into parse trees using :py:func:`get_types_from_idl() <rosbags.typesys.get_types_from_idl>` or :py:func:`get_types_from_msg() <rosbags.typesys.get_types_from_msg>`, and second the types are registered in the type system via :py:func:`register_types() <rosbags.typesys.register_types>`. The following example shows how to add messages type definitions from ``.msg`` and ``.idl`` files:
.. code-block:: python
from pathlib import Path
from rosbags.typesys import get_types_from_idl, get_types_from_msg, register_types
idl_text = Path('foo_msgs/msg/Foo.idl').read_text()
msg_text = Path('bar_msgs/msg/Bar.msg').read_text()
# plain dictionary to hold message definitions
add_types = {}
# add all definitions from one idl file
add_types.update(get_types_from_idl(idl_text))
# add definition from one msg file
add_types.update(get_types_from_msg(msg_text, 'bar_msgs/msg/Bar'))
# make types available to rosbags serializers/deserializers
register_types(add_types)