Building the nRF Connect SDK documentation¶
The nRF Connect SDK documentation is written using the reStructuredText markup language (.rst file extension) with Sphinx extensions and processed using Sphinx. API documentation is included from Doxygen comments.
See Documentation overview in the Zephyr developer guide for information about reStructuredText.
Before you start¶
Before you can build the documentation, install the nRF Connect SDK as described in Installing the nRF Connect SDK manually. Make sure that you have installed the required Python dependencies.
See Installing the documentation processors in the Zephyr developer guide for information about installing the required tools to build the documentation and their supported versions.
In addition to these tools, you must install mscgen and make sure the mscgen
executable is in your PATH
.
Note
On Windows, the Sphinx executable sphinx-build.exe
is placed in the Scripts
folder of your Python installation path.
Depending on how you have installed Python, you might need to add this folder to your PATH
environment variable.
Follow the instructions in Windows Python Path if needed.
Documentation structure¶
All documentation build files are located in the ncs/nrf/doc
folder.
The nrf
subfolder in that directory contains all .rst
source files that are not directly related to a sample application or a library.
Documentation for samples and libraries are provided in a README.rst
or .rst
file in the same directory as the code.
Building the documentation output requires building output for all documentation sets.
Currently, there are four sets: nrf, nrfxlib, zephyr, and mcuboot (covering the contents of bootloader/mcuboot
).
Since there are links from the ncs documentation set into other documentation sets, the other documentation sets must be built first.
Building documentation output¶
Complete the following steps to build the documentation output:
Open a shell and enter the doc folder
ncs/nrf/doc
.On Windows:
Navigate to
ncs/nrf
.Hold shift and right-click on the
doc
folder. Select Open command window here.
On Linux or macOS:
Open a shell window.
Navigate to
ncs/nrf/doc
. If the ncs folder is in your home directory, enter:cd ~/ncs/nrf/doc
Generate the Ninja build files:
cmake -GNinja -B_build .
Enter the generated build folder:
cd _build
Run ninja to build the documentation:
ninja build-all
This command will build all documentation sets. Note that this process can take quite some time.
Alternatively, if you want to build each documentation set separately, complete the following steps:
Run ninja to build the Kconfig documentation:
ninja kconfig-html
Run ninja to build the Zephyr documentation:
ninja zephyr
This step can take up to 15 minutes.
Run ninja to build the mcuboot documentation:
ninja mcuboot
Run ninja to build the nrfxlib inventory file (used by nrf):
ninja nrfxlib-inventory
Run ninja to build the nRF Connect SDK documentation:
ninja nrf
Run ninja to build the nrfxlib documentation:
ninja nrfxlib
The documentation output is written to the _build/html
folder.
Double-click the index.html
file to display the documentation in your browser.
Tip
If you modify or add RST files, you do not need to rerun the full documentation build.
For simple changes, it is sufficient to run the substep that builds the respective documentation (for example, only ninja nrf
for changes to the nRF Connect SDK documentation).
If this results in unexpected build errors, follow Caching and cleaning and rerun ninja build-all
.
Caching and cleaning¶
To speed up the documentation build, Sphinx processes only those files that have been changed since the last build. In addition, RST files are copied to a different location during the build process. This mechanism can cause outdated or deleted files to be used in the build, or the navigation to not be updated as expected.
If you experience any such problems, clean the build folders before you run the documentation build. Note that this will cause the documentation to be built from scratch, which takes a considerable time.
To clean the build folders for the Zephyr documentation:
ninja clean-zephyr
To clean the build folders for the nrfxlib documentation:
ninja clean-nrfxlib
To clean the build folders for the MCUboot documentation:
ninja clean-mcuboot
To clean the build folders for the nRF Connect SDK documentation:
ninja clean-nrf
Out-of-tree builds¶
Out-of-tree builds are also supported, so you can actually build from outside the source tree:
# On Linux/macOS
cd ~
source ncs/zephyr/zephyr-env.sh
cd ~
mkdir build
# On Windows
cd %userprofile%
ncs\zephyr\zephyr-env.cmd
mkdir build
# Use cmake to configure a Ninja-based build system:
cmake -GNinja -Bbuild/ -Hncs/nrf/doc
# Now run ninja on the generated build system:
ninja -C build/ zephyr
ninja -C build/ mcuboot
ninja -C build/ nrfxlib-inventory
ninja -C build/ nrf
ninja -C build/ nrfxlib
# If you modify or add .rst files in the nRF repository, run ninja again:
ninja -C build/ nrf
If you want to build the documentation from scratch, delete the contents of the build folder and run cmake
and then ninja
again.
Different versions¶
Documentation sets for different versions of the nRF Connect SDK are defined in the doc/versions.json
file.
This file is used to display the version drop-down in the top-left corner of the documentation.
The version drop-down is displayed only if the documentation files are organized in the required folder structure and the documentation is hosted on a web server. To test the version drop-down locally, complete the following steps:
In the documentation build folder (for example,
_build
), rename thehtml
folder tolatest
.Open a command window in the documentation build folder and enter the following command to start a Python web server:
python -m http.server
Access http://localhost:8000/latest/index.html with your browser to see the documentation.
To add other versions of the documentation to your local documentation output, build the versions from a tagged release and rename the html
folder to the respective version (for example, 1.5.1
).