nx/docs/shared/recipes/tips-n-tricks/wait-for-tasks.md
2023-08-28 12:39:31 +02:00

75 lines
2.2 KiB
Markdown

# Wait for Tasks to Finish
There are a couple ways to ensure that a set up task has been run before you run a particular task.
The most common solution is to use the [`dependsOn` property](/reference/project-configuration#dependson). This works regardless of what executor the task is using. Once the dependent tasks have completed, the primary task will start.
If you are using the `@nx/js:node` executor, you can also use the [`waitUntilTargets` option](/packages/js/executors/node#waituntiltargets) of that executor. Once the dependent tasks emit something to the console, the primary task will start.
## dependsOn
If you have a React app called `store` and a database project called `db`, you may want to run `nx clean db` before you run `nx e2e store`.
To set that up, edit the `store` app's `project.json` file:
{% tabs %}
{% tab label="Version 16+" %}
```json {% fileName="/apps/store/project.json" %}
{
"targets": {
"e2e": {
"dependsOn": [
{
"projects": ["db"],
"target": "clean"
}
]
}
}
}
```
{% /tab %}
{% tab label="Version < 16" %}
```jsonc {% fileName="/apps/store/project.json" %}
{
"targets": {
"clean-db": {
// Workaround task
"command": "nx clean db"
},
"e2e": {
"dependsOn": ["clean-db"] // Run clean-db on this project
}
}
}
```
{% /tab %}
{% /tabs %}
This will make it so that all you need to do is run `nx e2e store` and Nx will make sure that `nx clean db` is run first.
## waitUntilTargets
If you have a Node api called `api` and a database project called `db`, you may want to run `nx serve db` any time you run `nx serve api`.
To set that up, edit the `api` app's `project.json` file:
```json {% fileName="/apps/api/project.json" %}
{
"targets": {
"serve": {
"executor": "@nx/js:node",
"options": {
"waitUntilTargets": ["db:serve"]
}
}
}
}
```
With this configuration in place, if you run `nx serve api`, Nx will first run `nx serve db`. The `nx serve api` process will not be launched until `nx serve db` outputs something to the console. Then both processes will continue executing in parallel. When you kill the main process, both the `db` and `api` processes will be stopped.