Pass Args to Commands
When you have an inferred task (or an explicitly defined task using the nx:run-commands executor) running a command, there'll come a time when you'll need to pass args to the underlying command being run. This recipe explains how you can achieve that.
Example project and tasks
For this recipe we'll use a project with the following project.json file:
1{
2 "sourceRoot": "apps/my-app/src",
3 "projectType": "application",
4 "targets": {}
5}
6And the following final configuration:
my-app
Root: apps/my-app
Type:application
Targets
build
vite build
Cacheablepreview
vite preview
serve
vite serve
test
vitest run
Cacheable
We'll focus on the build target of the project. If you expand the build target in the Project Details View above, you'll see that it runs the command vite build. In the next sections, we'll see how to provide --assetsInlineLimit=2048 and --assetsDir=static/assets args to that command.
Pass args in the project.json task configuration
To statically pass some extra args to a specific project, you can update its project.json file. You can do it by either providing the args as individual options or by providing the args option:
Support for providing command args as options was added in Nx v18.1.1.
1{
2 "sourceRoot": "apps/my-app/src",
3 "projectType": "application",
4 "targets": {
5 "build": {
6 "options": {
7 "assetsInlineLimit": 2048,
8 "assetsDir": "static/assets"
9 }
10 }
11 }
12}
13Args specified in the args option take precedence and will override any arg specified as an option with the same name. So, defining both "args": ["--assetsDir=static/assets"] and "assetsDir": "different/path/to/assets" will result in Nx running the command with --assetsDir=static/assets.
Pass args in the targetDefaults for the task
To provide the same args for all projects in the workspace, you need to update the task configuration in the nx.json file. Similar to the previous section, you can do it by either providing the args as individual options or by providing the args option:
1{
2 "targetDefaults": {
3 "build": {
4 "options": {
5 "assetsInlineLimit": 2048,
6 "assetsDir": "static/assets"
7 }
8 }
9 }
10}
11If multiple targets with the same name run different commands (or use different executors), do not set options in targetDefaults. Different commands would accept different options, and the target defaults will apply to all targets with the same name regardless of the command they run. If you were to provide options in targetDefaults for them, the commands that don't expect those options could throw an error.
Pass args when running the command in the terminal
To pass args in a one-off manner when running a task, you can also provide them as individual options or by providing the --args option when running the task:
❯
nx build my-app --assetsInlineLimit=2048 --assetsDir=static/assets
If you provide an arg with the same name as an Nx CLI option (e.g. --configuration) or an nx:run-commands option (e.g. --env), the arg will be parsed as an option for the Nx CLI or the executor and won't be forwarded to the underlying command. You should provide the arg using the -args option in such cases.
You can also provide an arg with the same name to both the Nx CLI and the underlying command. For example, to run the ci configuration of a test target that runs the command detox test and pass the --configuration arg to the command, you can run:
❯
nx test mobile-e2e --configuration=ci --args="--configuration=ios.sim.release"