Build RPM packages using node modules offline

By default, npm download dependencies from registry.npmjs.org and hides the details in the node_modules subdirectory. Its job is to resolve version dependencies and provide it to Node application in such a way that it satisfied the dependencies and does not conflict with other dependencies. To be able to build and rebuild a package from sources, we will need to be able to install and possibly update these dependencies in a networkless environment like OBS.

When npm installs dependencies, it will create a package-lock.json that will contain the entire list of packages that can possible exist in the node_modules directory structure.

The purpose of this tool is to parse package-lock.json and prepare all externally download sources for use by npm during rpmbuild.

runtime requirements

npm 7+ is required to produce package-lock.json with lockfileVersion:2

As OBS service

• Get package-lock.json with localfileVersion: 2. For example,
  • npm install --package-lock-only --legacy-peer-deps --ignore-scripts with npm 7+
  • --legacy-peer-deps is required to fetch peer dependencies from remote locally so they are available during peer resolution in the VM. Without this you may get additional warnings during install.
• Make sure to put the package-lock.json next to the spec file and remove it from the sources. Sources should only have package.json, even if they ship a compatible package-lock.json
• Add the following line to the spec file:

  %include  %{_sourcedir}/node_modules.spec.inc
  

• Create file _service with the following content:

  <services>
    <service name="node_modules" mode="manual">
      <param name="cpio">node_modules.obscpio</param>
      <param name="output">node_modules.spec.inc</param>
      <param name="source-offset">10000</param>
    </service>
  </services>
  

• osc service manualrun
  • this generates the NPM dependency archive along with its source URLs
• osc add node_modules.obscpio
• osc add node_modules.spec.inc
• osc commit

Example

Source10:       package-lock.json
Source11:       node_modules.spec.inc
%include        %{_sourcedir}/node_modules.spec.inc
BuildRequires:  local-npm-registry

[...]

%prep
%setup
local-npm-registry %{_sourcedir} install --also=dev

[...]

%build
npm run build

In Practice

https://build.opensuse.org/package/show/openSUSE:Factory/cockpit-podman

External Resources

https://github.com/openSUSE/npm-localhost-proxy