[libcamera-devel] [PATCH v2] package metadata

[Christian Rauch]

Hi Kieran,

Am 15.08.22 um 10:18 schrieb Kieran Bingham:
> Quoting Christian Rauch via libcamera-devel (2022-08-13 13:31:18)
>> This metadata file provides information, amongst others, about the version,
>> licence, maintainers and build dependencies. This file is used by build
>> systems (catkin, colcon) to manage a dependency graph and resolve those
>> dependencies automatically.
>>
>> The file structure is defined at: https://www.ros.org/reps/rep-0149.html
>>
>> Signed-off-by: Christian Rauch <Rauch.Christian at gmx.de>
>> ---
>>  package.xml | 31 +++++++++++++++++++++++++++++++
>>  1 file changed, 31 insertions(+)
>>  create mode 100644 package.xml
>>
>> diff --git a/package.xml b/package.xml
>> new file mode 100644
>> index 00000000..2264efd9
>> --- /dev/null
>> +++ b/package.xml
>> @@ -0,0 +1,31 @@
>
> Do we need to add any licence information in here?, or in .reuse/dep5 at
> all?

The licence information should go into the tag "license" (see below).

>
>> +<?xml version="1.0"?>
>> +<?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
>> +<package format="3">
>> +  <name>libcamera</name>
>> +
>> +  <version>0.0.0</version>
>
> If this file was generated by meson, it could populate this field. But I
> fear that's a bit 'chicken and egg'.

This file is parsed before the build is started. Otherwise, required
dependencies couldn't be fetched or built before.

>
> How does ROS handle sources? Does it include libcamera as a subproject?
> or using the repo tool perhaps?

Either way. You can check out the libcamera as part of your workspace
(that's what I am currently doing) and then have it automatically built
(by catkin or colcon) if it is required by another project, or you can
distribute a binary version of it in the ROS repo and have it fetched
via rosdep. Anyway, the dependency information is required such that
rosdep can download required dependences or colcon can build packages in
the right order.

>
>> +  <description>An open source camera stack and framework for Linux, Android, and ChromeOS</description>
>> +
>> +  <maintainer email="libcamera-devel at lists.libcamera.org">libcamera project</maintainer>
>> +
>> +  <license>LGPL-2.1</license>
>
> That's correct for the library itself, but not the utilities or other
> toolings. And the IPA modules have different licence constraints.
>
> Does a package.xml file have the ability to state multiple licences, or
> specify what the license applies to?
>
Good point. You can specify multiple licences [1] by using the "license"
tag multiple times. I think for mixed licencing, you are supposed to add
a "SPDX Identifier" [2] to the top of every file in order to make this
machine-readable.

[1] https://www.ros.org/reps/rep-0149.html#license-multiple-but-at-least-one
[2] https://spdx.org/licenses/
>
>> +
>> +  <url>https://libcamera.org</url>
>> +
>> +  <buildtool_depend>python3-meson-pip</buildtool_depend>
>> +  <buildtool_depend>ninja-build</buildtool_depend>
>> +  <buildtool_depend>pkg-config</buildtool_depend>
>> +
>> +  <build_depend>python3-yaml</build_depend>
>> +  <build_depend>python3-ply</build_depend>
>> +  <build_depend>python3-jinja2</build_depend>
>> +
>> +  <depend>yaml</depend>
>> +  <depend>libgnutls28-dev</depend>
>> +  <depend>libudev-dev</depend>
>> +
>> +  <export>
>> +    <build_type>meson</build_type>
>> +  </export>
>> +</package>
>> --
>> 2.34.1
>>