Nx Meta Platform open-source components

// Copyright 2018-present Network Optix, Inc. Licensed under MPL 2.0: www.mozilla.org/MPL/2.0/

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Introduction

This repository nx_open contains Network Optix Meta Platform open-source components - the source code and specifications which are used to build all Powered-by-Nx products including Nx Witness Video Management System (VMS).

Currently, the main VMS component which can be built from this repository is the Desktop Client. Other notable components which are parts of the Desktop Client, but can be useful independently, include the Nx Kit library (artifacts/nx_kit/) - see its readme.md for details.

Most of the source code and other files are licensed under the terms of Mozilla Public License 2.0 (unless specified otherwise in the files) which can be found in the license_mpl2.md file in the licenses/ directory in the root directory of the repository.

ATTENTION: This document provides only brief information about the build process and its prerequisites, specific to the current branch. For the most actual instructions how to set up the prerequisites, explanation of the build system internals, and recommendations for using the build and development tools, refer to the following document in the master branch of this repository: build.md

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Free and open-source software notices

The "Network Optix Meta Platform open-source components" software incorporates, depends upon, interacts with, or was developed using a number of free and open-source software components. The full list of such components can be found at OPEN SOURCE SOFTWARE DISCLOSURE. Please see the linked component websites for additional licensing, dependency, and use information, as well as the component source code.

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Build environment

Supported target platforms and architectures:

• Windows 10 x64 (Microsoft Visual Studio).
• Linux Ubuntu 18.04 and 20.04 (GCC or Clang) x64, ARM 32/64 (cross-compiling on Linux x64).
• MacOS Monterey 12.6.3 (Xcode with Clang) x64, Apple M1/M2.

Build prerequisites:

• Python 3.8+ - should be available on PATH as python, and for macOS and Ubuntu also as python3.
• Pip - should be available on PATH as pip and be installed for the Python interpreter used by the build.
• CMake 3.20+, Ninja 1.10.2+, Conan 1.46.x - recommended to be installed via pip:

  git checkout master # The master branch contains a universal requirements.txt.
  pip install -r requirements.txt
  

  On Windows, run pip as an Administrator; on Linux - re-login to make ~/.local/bin/ appear on PATH.
• Linux: Build and runtime dependencies:

  sudo apt install -y \
      chrpath libtinfo5 zlib1g-dev libopenal-dev mesa-common-dev libgl1-mesa-dev libtool \
      libglu1-mesa-dev libldap2-dev libxfixes-dev libxss-dev libgstreamer1.0-0 p7zip-full \
      libgstreamer-plugins-base1.0-0 libxslt1.1 pkg-config autoconf libxcb-xinerama0 \
      libfreetype6-dev libfontconfig1-dev
  

  • NOTE: The compiler is downloaded as a Conan artifact during the CMake Generation stage - compilers installed in the Linux system (if any) are not used.
• Windows: Microsoft Visual Studio 2022, Community Edition; select the components:
  • "The Workload" -> "Desktop development with C++"
  • "Individual components" -> "C++ CMake tools for Windows"
• MacOS: Xcode Command Line Tools 14.2+, Homebrew 3.6.20+, build and runtime dependencies:

  brew install zlib-ng openal-soft mesa mesa-glu mesalib-glw openldap libxfixes \
      libxscrnsaver gstreamer gst-plugins-base libxslt pkgconf
  

  • For Apple M1/M2, install Rosetta 2:

  /usr/sbin/softwareupdate --install-rosetta --agree-to-license
  

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Building VMS Desktop Client

The Client uses in its GUI a collection of texts and graphics called a Customization Package; it defines the branding of the VMS. The Customization Package comes as a zip file. A default one is taken from Conan - the Client will be branded as Nx Meta and will show placeholders for such traits as the company name, web site and End-User License Agreement text. If you want to define these traits, create a "Custom Client" entity on the Nx Meta Developer Portal and download the generated Customization Package zip at https://meta.nxvms.com/developers/custom-clients/. Customization Packages with branding other than Nx Meta can be available there as well.

All the commands necessary to perform the CMake Configuration and Build stages are written in the scripts build.sh (for Linux and MacOS) and build.bat (for Windows) located in the repository root. Please treat these scripts as a quick start aid, study their source, and feel free to use your favorite C++ development workflow instead.

The scripts create/use the build directory as a sibling to the repository root directory, having added the -build suffix. Here we assume the repository root is nx_open/, so the build directory will be nx_open-build/.

ATTENTION: If the generation fails for any reason, remove CMakeCache.txt manually before the next attempt of running the build script.

Below are the usage examples, where <build> is ./build.sh for Linux and macOS, and build.bat for Windows.

• To make a clean Debug build, delete the build directory (if any), and run the command:

  <build>
  

  The built executables will be placed in nx_open-build/bin/.

• To make a clean Release build with the distribution package and unit test archive, delete the build directory (if any), and run the command:

  <build> -DdeveloperBuild=OFF
  

  The built distribution packages and unit test archive will be placed in nx_open-build/distrib/. To run the unit tests, unpack the unit test archive and run all the executables in it either one-by-one, or in parallel.

• To use the obtained Customization Package rather than the default one coming from Conan (Nx-Meta-branded with placeholders), add the following arguments to the <build> script:

  -DcustomizationPackageFile=<customization.zip>
  

  NOTE: The value in the "id": field of description.json inside the specified zip file must match the one in the Server in order to be able to connect to it.

• To perform an incremental build after some changes, run the <build> script without arguments.

  • Note that there is no need to explicitly call the Generation stage after adding/deleting source files or altering the build system files, because ninja_tool.py properly handles such cases - the Generation stage will be called automatically when needed.

For cross-compiling on Linux or MacOS, set the CMake variable <targetDevice>: add the argument -DtargetDevice=<value>, where is one of the following:

• linux_x64
• linux_arm64
• linux_arm32
• macos_x64
• macos_arm64

Building and debugging in Visual Studio IDE is also supported: run the Generation stage from the command line, it will create CMakeSettings.json and launch.vs.json, then open the project.

It is recommended to set the environment variable NX_CONAN_DOWNLOAD_CACHE to the full path of a directory that will be used to avoid re-downloading all the artifacts from the internet for every clean build; for example, create the directory conan_cache/ next to the repository root and the build directories.

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Signing executable files

• Windows:

  There is an option of signing the built executables (including the distribution file itself) with the software publisher certificate. To perform it, a valid certificate file in the PKCS#12 format is needed.

  Signing is performed by the signtool.py script which is a wrapper around native Windows signtool.exe. To enable signing, the following preparation steps must be done:

  • Save the publisher certificate file somewhere in your file system.

  • Create (preferably outside of the source tree) the configuration file. This file must contain the following fields:

    • file: the path to the publisher certificate file. It must be either an absolute path or a path relative to the directory where the configuration file resides.
    • password: the password protecting the publisher certificate file.
    • timestamp_servers (optional): a list of the URLs of the trusted timestamping server. If this field is present in the configuration file, the signed file will be time-stamped using one of the listed servers. If this field is absent, the signed file will not be time-stamped.

    The example of a configuration file can be found in build_utils/signtool/config/config.yaml.

  • Add a CMake argument -DsigntoolConfig=<configuration_file_path> to the Generation stage. If this argument is missing, no signing will be performed.

  Also you can sign any file manually by calling signtool.py directly: python build_utils/signtool/signtool.py --config <configuration_file> --file <unsigned_file> --output <signed_file>

  To test the signing procedure, you can use a self-signed certificate. To generate such certificate, you can use the file build_utils/signtool/genkey/genkey_signtool.bat. When run, it creates the certificate.p12 file and a couple of auxillary *.pem files in the same directory where it is run. We recommend to move these files outside of the source directory to maintain the out-of-source build concept.

• Linux:

  Signing is not required; no tools or instructions are provided.

• MacOS:

  A signing tool suitable for standalone use is being developed and will likely be provided in the future. As for now, you can use your regular signing procedure that you involve for your other MacOS developments.

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Running VMS Desktop Client

The VMS Desktop Client can be run directly from the build directory, without installing a distribution package.

After the successful build, the Desktop Client executable is located in nx_open-build/bin/; its name may depend on the Customization Package.

For Linux and MacOS, just run the Desktop Client executable.

For Windows, before running the Desktop Client executable or any other executable built, run the following script (generated by Conan during the build) in the console, which properly sets PATH and some other environment variables:

nx_open-build/activate_run.bat

To restore the original variable values including PATH, you may run the following script:

nx_open-build/deactivate_run.bat

Compatible VMS Server versions

The Desktop Client built from the open-source repository can only connect to a compatible VMS Server. Because the VMS Server sources are not publicly available, such Server can only be obtained from any public VMS release, including the official VMS releases, and the regular preview releases called Nx Meta VMS.

For any given public VMS release, the compatibility is guaranteed only for the Client built from the same commit as the Server. The particular commit can be identified in the repository by its git tag. The public release tags look like vms/4.2/12345_release_all or vms/5.0/34567_beta_meta_R2.

Clients built from further commits in the same branch may retain compatibility with the publicly released Server for a while, but at some point may lose the compatibility because of some changes introduced synchronously into the Client and the Server parts of the source code. Thus, it is recommended to base the Client modification branches from tagged commits corresponding to the public releases, including Nx Meta VMS releases, and rebase them as soon as next public release from this branch is available.

ATTENTION: Besides having the compatible code, to be able to work together, the Client and the Server have to use Customization Packages with the same <customization_id> value.

During the Generation stage, the build system tries to determine the compatible Server version checking the git tags. It searches for the first commit common for the current branch and one of the "protected" branches (corresponding to stable VMS versions), and checks if it has a "release" tag of the form "vms/#.#/#####_...". If no such tag is found, the build number is set to 0 and a warning is produced, otherwise the build number is extracted from the tag. To bypass this algorithm, pass "-DbuildNumber=<custom_build_number>" to cmake; to get back to it, make a clean build or pass -DbuildNumber=AUTO.

Automatic VMS updates

The VMS product includes a comprehensive auto-update support, but this feature is turned off for the open-source Desktop Client, because it would simply re-write a custom-built Desktop Client with the new version of the Desktop Client built by Nx. Note that the VMS admin still can force such an automatic update, with the mentioned consequences.

Technically it is possible to specify a custom Update server in the VMS Server settings, deploy a custom Update server, and prepare the update packages and meta-information according to the VMS standard, so that the automatic updates will work with a custom VMS built from open source. In the future, instructions and/or tools for this will likely be provided.