[PATCH 0/2] bitbake-setup: clarify configuration merging and add a notes property

[PATCH 0/2] bitbake-setup: clarify configuration merging and add a notes property

[Ernest Van Hoecke]

This series aims to clarify the configurating merging, since it is not
necessarily obvious.

The second patch uses this and adds a "notes" string property that can
be used to populate "conf-notes.txt" when bb-layers is used instead of 
oe-template. For this and the "description" property, it's good to be
aware that strings get concatenated when they occur in nested
configurations.

Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>

---
Ernest Van Hoecke (2):
      bitbake-setup: clarify configuration merging
      bitbake-setup: write notes for generated build configs

 bin/bitbake-setup                                             |  3 ++-
 .../bitbake-user-manual-environment-setup.rst                 | 11 +++++++++++
 lib/bb/tests/setup.py                                         |  4 ++++
 setup-schema/bitbake-setup.schema.json                        |  4 ++++
 4 files changed, 21 insertions(+), 1 deletion(-)
---
base-commit: e9a06f79d9ec767c9d95470be78b006d6fd0d59c
change-id: 20260529-bb-setup-notes-0663341b0478

Best regards,
-- 
Ernest Van Hoecke <ernest.vanhoecke@toradex.com>

[PATCH 1/2] bitbake-setup: clarify configuration merging

[Ernest Van Hoecke]

From: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>

When nested configurations are used and the same key is present in both
configs being merged, the Python "+" behaviour is used. This leads to
lists being appended and strings being concatenated. The first is an
intuitive behaviour when specifying a tree of configs, the latter might
not be.

Clarify the configuration merging behaviour explicitly in the docs.

Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
---
 doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst b/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
index 77fc4c3dcba0..1252f22c823a 100644
--- a/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
+++ b/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
@@ -1068,6 +1068,12 @@ They contain the following sections:
       configuration choices by putting together information from a leaf
       configuration and all of its ancestors.
 
+      When the same keyword is present in a nested configuration and in one of
+      its ancestors, the values are merged with Python ``+`` semantics. For
+      example, lists are appended and strings are concatenated directly. String
+      values such as ``description`` should include any needed separators in
+      the configuration data.
+
    -  ``bb-env-passthrough-additions`` (*optional*): List of environment
       variables to include in :term:`BB_ENV_PASSTHROUGH_ADDITIONS`.
 

-- 
2.43.0

Re: [bitbake-devel] [PATCH 1/2] bitbake-setup: clarify configuration merging

[Alexander Kanavin]

Thanks, this lgtm!

Alex

On Fri, 29 May 2026 at 17:00, Ernest Van Hoecke via
lists.openembedded.org
<ernestvanhoecke=gmail.com@lists.openembedded.org> wrote:
>
> From: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
>
> When nested configurations are used and the same key is present in both
> configs being merged, the Python "+" behaviour is used. This leads to
> lists being appended and strings being concatenated. The first is an
> intuitive behaviour when specifying a tree of configs, the latter might
> not be.
>
> Clarify the configuration merging behaviour explicitly in the docs.
>
> Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
> ---
>  doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst b/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
> index 77fc4c3dcba0..1252f22c823a 100644
> --- a/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
> +++ b/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
> @@ -1068,6 +1068,12 @@ They contain the following sections:
>        configuration choices by putting together information from a leaf
>        configuration and all of its ancestors.
>
> +      When the same keyword is present in a nested configuration and in one of
> +      its ancestors, the values are merged with Python ``+`` semantics. For
> +      example, lists are appended and strings are concatenated directly. String
> +      values such as ``description`` should include any needed separators in
> +      the configuration data.
> +
>     -  ``bb-env-passthrough-additions`` (*optional*): List of environment
>        variables to include in :term:`BB_ENV_PASSTHROUGH_ADDITIONS`.
>
>
> --
> 2.43.0
>
>
> -=-=-=-=-=-=-=-=-=-=-=-
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>

[PATCH 2/2] bitbake-setup: write notes for generated build configs

[Ernest Van Hoecke]

From: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>

For bb-layers configurations, bitbake-setup currently writes an empty
"conf-notes.txt". Configurations using "oe-template" get this file from
the template.

Add an optional field called "notes" to configurations that populates
this field when "bb-layers" is used instead of "oe-template".

Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
---
 bin/bitbake-setup                                                 | 3 ++-
 doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst | 5 +++++
 lib/bb/tests/setup.py                                             | 4 ++++
 setup-schema/bitbake-setup.schema.json                            | 4 ++++
 4 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/bin/bitbake-setup b/bin/bitbake-setup
index 220540f7f9ca..e22e5b77bde1 100755
--- a/bin/bitbake-setup
+++ b/bin/bitbake-setup
@@ -301,7 +301,8 @@ def setup_bitbake_build(bitbake_config, layerdir, setupdir, thisdir, update_bb_c
             f.write(bitbake_config["description"] + "\n")
 
         with open(os.path.join(build_conf_dir, "conf-notes.txt"), 'w') as f:
-            f.write("")
+            notes = bitbake_config.get("notes")
+            f.write(notes + "\n" if notes else "")
 
     def _make_init_build_env(builddir, oeinitbuildenvdir):
         builddir = os.path.realpath(builddir)
diff --git a/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst b/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
index 1252f22c823a..e99cf7b3415d 100644
--- a/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
+++ b/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
@@ -1057,6 +1057,11 @@ They contain the following sections:
       snippet. This is what is prompted during the
       :ref:`ref-bbsetup-command-init` command execution.
 
+   -  ``notes`` (*optional*): additional information written to
+      ``build/conf/conf-notes.txt`` when ``bitbake-setup`` generates the build
+      configuration from ``bb-layers``. For ``oe-template`` configurations,
+      this file is provided by the template.
+
    -  ``configurations``: Configurations can recursively contain as many nested
       configurations as needed. This will create more choices when running the
       :ref:`ref-bbsetup-command-init` command.
diff --git a/lib/bb/tests/setup.py b/lib/bb/tests/setup.py
index 638d56d3bb32..ffe390db1bda 100644
--- a/lib/bb/tests/setup.py
+++ b/lib/bb/tests/setup.py
@@ -136,6 +136,7 @@ print("BBPATH is {{}}".format(os.environ["BBPATH"]))
             {
                 "name": "gadget-notemplate",
                 "description": "Gadget notemplate configuration",
+                "notes": "Gadget notemplate notes",
                 "bb-layers": ["layerA","layerB/meta-layer"],
                 "oe-fragments": ["test-fragment-1"]
             },
@@ -249,6 +250,9 @@ print("BBPATH is {{}}".format(os.environ["BBPATH"]))
         else:
             with open(os.path.join(bb_conf_path, 'conf-summary.txt')) as f:
                 self.assertIn(bitbake_config["description"], f.read())
+            with open(os.path.join(bb_conf_path, 'conf-notes.txt')) as f:
+                expected_notes = bitbake_config.get("notes")
+                self.assertEqual(f.read(), expected_notes + "\n" if expected_notes else "")
             with open(os.path.join(bb_conf_path, 'bblayers.conf')) as f:
                 bblayers = f.read()
                 for l in bitbake_config["bb-layers"]:
diff --git a/setup-schema/bitbake-setup.schema.json b/setup-schema/bitbake-setup.schema.json
index be8772db1b2d..6a39e66a0ae4 100644
--- a/setup-schema/bitbake-setup.schema.json
+++ b/setup-schema/bitbake-setup.schema.json
@@ -41,6 +41,10 @@
                                 "type": "string",
                                 "description": "Human-readable description of the configuration"
                             },
+                            "notes": {
+                                "type": "string",
+                                "description": "Extra notes that populate conf-notes.txt when bb-layers is used"
+                            },
                             "bb-layers": {
                                 "type": "array",
                                 "description": "List of BitBake layer paths to include, relative to the layers download directory",

-- 
2.43.0

Re: [bitbake-devel] [PATCH 2/2] bitbake-setup: write notes for generated build configs

[Alexander Kanavin]

Thanks, this lgtm too.

Alex

On Fri, 29 May 2026 at 17:00, Ernest Van Hoecke via
lists.openembedded.org
<ernestvanhoecke=gmail.com@lists.openembedded.org> wrote:
>
> From: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
>
> For bb-layers configurations, bitbake-setup currently writes an empty
> "conf-notes.txt". Configurations using "oe-template" get this file from
> the template.
>
> Add an optional field called "notes" to configurations that populates
> this field when "bb-layers" is used instead of "oe-template".
>
> Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
> ---
>  bin/bitbake-setup                                                 | 3 ++-
>  doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst | 5 +++++
>  lib/bb/tests/setup.py                                             | 4 ++++
>  setup-schema/bitbake-setup.schema.json                            | 4 ++++
>  4 files changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/bin/bitbake-setup b/bin/bitbake-setup
> index 220540f7f9ca..e22e5b77bde1 100755
> --- a/bin/bitbake-setup
> +++ b/bin/bitbake-setup
> @@ -301,7 +301,8 @@ def setup_bitbake_build(bitbake_config, layerdir, setupdir, thisdir, update_bb_c
>              f.write(bitbake_config["description"] + "\n")
>
>          with open(os.path.join(build_conf_dir, "conf-notes.txt"), 'w') as f:
> -            f.write("")
> +            notes = bitbake_config.get("notes")
> +            f.write(notes + "\n" if notes else "")
>
>      def _make_init_build_env(builddir, oeinitbuildenvdir):
>          builddir = os.path.realpath(builddir)
> diff --git a/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst b/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
> index 1252f22c823a..e99cf7b3415d 100644
> --- a/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
> +++ b/doc/bitbake-user-manual/bitbake-user-manual-environment-setup.rst
> @@ -1057,6 +1057,11 @@ They contain the following sections:
>        snippet. This is what is prompted during the
>        :ref:`ref-bbsetup-command-init` command execution.
>
> +   -  ``notes`` (*optional*): additional information written to
> +      ``build/conf/conf-notes.txt`` when ``bitbake-setup`` generates the build
> +      configuration from ``bb-layers``. For ``oe-template`` configurations,
> +      this file is provided by the template.
> +
>     -  ``configurations``: Configurations can recursively contain as many nested
>        configurations as needed. This will create more choices when running the
>        :ref:`ref-bbsetup-command-init` command.
> diff --git a/lib/bb/tests/setup.py b/lib/bb/tests/setup.py
> index 638d56d3bb32..ffe390db1bda 100644
> --- a/lib/bb/tests/setup.py
> +++ b/lib/bb/tests/setup.py
> @@ -136,6 +136,7 @@ print("BBPATH is {{}}".format(os.environ["BBPATH"]))
>              {
>                  "name": "gadget-notemplate",
>                  "description": "Gadget notemplate configuration",
> +                "notes": "Gadget notemplate notes",
>                  "bb-layers": ["layerA","layerB/meta-layer"],
>                  "oe-fragments": ["test-fragment-1"]
>              },
> @@ -249,6 +250,9 @@ print("BBPATH is {{}}".format(os.environ["BBPATH"]))
>          else:
>              with open(os.path.join(bb_conf_path, 'conf-summary.txt')) as f:
>                  self.assertIn(bitbake_config["description"], f.read())
> +            with open(os.path.join(bb_conf_path, 'conf-notes.txt')) as f:
> +                expected_notes = bitbake_config.get("notes")
> +                self.assertEqual(f.read(), expected_notes + "\n" if expected_notes else "")
>              with open(os.path.join(bb_conf_path, 'bblayers.conf')) as f:
>                  bblayers = f.read()
>                  for l in bitbake_config["bb-layers"]:
> diff --git a/setup-schema/bitbake-setup.schema.json b/setup-schema/bitbake-setup.schema.json
> index be8772db1b2d..6a39e66a0ae4 100644
> --- a/setup-schema/bitbake-setup.schema.json
> +++ b/setup-schema/bitbake-setup.schema.json
> @@ -41,6 +41,10 @@
>                                  "type": "string",
>                                  "description": "Human-readable description of the configuration"
>                              },
> +                            "notes": {
> +                                "type": "string",
> +                                "description": "Extra notes that populate conf-notes.txt when bb-layers is used"
> +                            },
>                              "bb-layers": {
>                                  "type": "array",
>                                  "description": "List of BitBake layer paths to include, relative to the layers download directory",
>
> --
> 2.43.0
>
>
> -=-=-=-=-=-=-=-=-=-=-=-
> Links: You receive all messages sent to this group.
> View/Reply Online (#19565): https://lists.openembedded.org/g/bitbake-devel/message/19565
> Mute This Topic: https://lists.openembedded.org/mt/119548246/1686489
> Group Owner: bitbake-devel+owner@lists.openembedded.org
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> -=-=-=-=-=-=-=-=-=-=-=-
>

Re: [bitbake-devel] [PATCH 2/2] bitbake-setup: write notes for generated build configs

[Antonin Godard]

On Fri May 29, 2026 at 5:00 PM CEST, Ernest Van Hoecke via lists.openembedded.org wrote:
> From: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
>
> For bb-layers configurations, bitbake-setup currently writes an empty
> "conf-notes.txt". Configurations using "oe-template" get this file from
> the template.
>
> Add an optional field called "notes" to configurations that populates
> this field when "bb-layers" is used instead of "oe-template".

Suggestion: call the field "conf-notes" so it matches the resulting filename?

Also, I supposed newlines must be explicitly written in the string ("\n")? Are
those properly converted, or does it need escaping of some sorts?

Thanks,
Antonin

Re: [docs] [bitbake-devel] [PATCH 2/2] bitbake-setup: write notes for generated build configs

[Alexander Kanavin]

On Mon, 1 Jun 2026 at 09:05, Antonin Godard via lists.yoctoproject.org
<antonin.godard=bootlin.com@lists.yoctoproject.org> wrote:
> Suggestion: call the field "conf-notes" so it matches the resulting filename?

I disagree. It's meant for general-purpose freeform notes about the
configuration; that they also get written into conf-notes.txt is an
implementation detail. It's also more consistent, as there's already
"description" which gets written into conf-summary.txt.

Alex

Re: [bitbake-devel] [PATCH 2/2] bitbake-setup: write notes for generated build configs

[Ernest Van Hoecke]

On Mon, Jun 01, 2026 at 09:05:17AM +0200, Antonin Godard wrote:
> On Fri May 29, 2026 at 5:00 PM CEST, Ernest Van Hoecke via lists.openembedded.org wrote:
> > From: Ernest Van Hoecke <ernest.vanhoecke@toradex.com>
> >
> > For bb-layers configurations, bitbake-setup currently writes an empty
> > "conf-notes.txt". Configurations using "oe-template" get this file from
> > the template.
> >
> > Add an optional field called "notes" to configurations that populates
> > this field when "bb-layers" is used instead of "oe-template".
> 
> Suggestion: call the field "conf-notes" so it matches the resulting filename?
> 
> Also, I supposed newlines must be explicitly written in the string ("\n")? Are
> those properly converted, or does it need escaping of some sorts?
> 
> Thanks,
> Antonin
> 

Hi Antonin,

Yes, I tested with some newlines explicitly written and this worked fine.
Since it just comes from a json string and is passed to `f.write()` I
don't believe any special escaping is necessary, just "\n" is fine.

My understanding is that the Python json library should handle this well
and converts it to a real newline in the python string.

Thanks,
Ernest

Re: [bitbake-devel] [PATCH 2/2] bitbake-setup: write notes for generated build configs

[Alexander Kanavin]

On Mon, 1 Jun 2026 at 14:53, Ernest Van Hoecke via
lists.openembedded.org
<ernestvanhoecke=gmail.com@lists.openembedded.org> wrote:

> Yes, I tested with some newlines explicitly written and this worked fine.
> Since it just comes from a json string and is passed to `f.write()` I
> don't believe any special escaping is necessary, just "\n" is fine.
>
> My understanding is that the Python json library should handle this well
> and converts it to a real newline in the python string.

I need to ask though: how practical and readable is it going to be,
when written into the json? Notes are meant as multiple paragraphs of
text, and it would be good to be able to write them that way, instead
of some specially-formatted single string.

Alex

Re: [bitbake-devel] [PATCH 2/2] bitbake-setup: write notes for generated build configs

[Ernest Van Hoecke]

On Mon, Jun 01, 2026 at 03:30:48PM +0200, Alexander Kanavin wrote:
> On Mon, 1 Jun 2026 at 14:53, Ernest Van Hoecke via
> lists.openembedded.org
> <ernestvanhoecke=gmail.com@lists.openembedded.org> wrote:
> 
> > Yes, I tested with some newlines explicitly written and this worked fine.
> > Since it just comes from a json string and is passed to `f.write()` I
> > don't believe any special escaping is necessary, just "\n" is fine.
> >
> > My understanding is that the Python json library should handle this well
> > and converts it to a real newline in the python string.
> 
> I need to ask though: how practical and readable is it going to be,
> when written into the json? Notes are meant as multiple paragraphs of
> text, and it would be good to be able to write them that way, instead
> of some specially-formatted single string.
> 
> Alex
>

I considered this and agree, there's no true beautiful solution here.
The description field also has this issue, granted, that's meant to be
much shorter than notes.

Since json doesn't support multiline strings, the only alternative is
making this field a list of strings and concatenating them in code. I'm
certainly open to that and can send a v2 doing it that way (it'd look
like an extra "\n".join()).
 
Ernest

Re: [bitbake-devel] [PATCH 2/2] bitbake-setup: write notes for generated build configs

[Alexander Kanavin]

On Mon, 1 Jun 2026 at 15:55, Ernest Van Hoecke
<ernestvanhoecke@gmail.com> wrote:
> I considered this and agree, there's no true beautiful solution here.
> The description field also has this issue, granted, that's meant to be
> much shorter than notes.
>
> Since json doesn't support multiline strings, the only alternative is
> making this field a list of strings and concatenating them in code. I'm
> certainly open to that and can send a v2 doing it that way (it'd look
> like an extra "\n".join()).

Yes. We're basically restricted by json's original purpose of being a
data transfer format, and not a config file format. (the "no comments"
restriction is in the same vein). It's a lot more human friendly than
xml, but still not friendly enough, by modern standards.

It's tempting to make it a reference to an external file, but this
wouldn't work well when the config is fetched with http:
$ bitbake-setup init https://my.server/some-build.conf.json
would have to also fetch the notes file.

A list of strings isn't horrible, perhaps either can be supported?

Alex