- `rebuild`: Compose rebuilds the service image based on the `build` section and recreates the service with the updated image.
- `restart`: Compose restarts the service container. Available with Docker Compose version 2.32.0 and later.
- `sync`: Compose keeps the existing service container(s) running, but synchronizes source files with container content according to the `target` attribute.
- `sync+restart`: Compose synchronizes source files with container content according to the `target` attribute, and then restarts the container. Available with Docker Compose version 2.23.0 and later.
- `sync+exec`: Compose synchronizes source files with container content according to the `target` attribute, and then executes a command inside the container. Available with Docker Compose version 2.32.0 and later.
#### `exec`
{{< summary-bar feature_name="Compose exec" >}}
`exec` is only relevant when `action` is set to `sync+exec`. Like [service hooks](services.md#post_start), `exec` is used to define the command to be run inside the container once it has started.
- `command`: Specifies the command to run once the container starts. This attribute is required, and you can choose to use either the shell form or the exec form.
- `user`: The user to run the command. If not set, the command is run with the same user as the main service command.
- `privileged`: Lets the command run with privileged access.
- `working_dir`: The working directory in which to run the command. If not set, it is run in the same working directory as the main service command.
- `environment`: Sets the environment variables to run the command. While the command inherits the environment variables defined for the service’s main command, this section lets you add new variables or override existing ones.
```yaml
services:
frontend:
image: ...
develop:
watch:
# sync content then run command to reload service without interruption
- path: ./etc/config
action: sync+exec
target: /etc/config/
exec:
command: app reload
```
#### `ignore`
The `ignore` attribute can be used to define a list of patterns for paths to be ignored. Any updated file
that matches a pattern, or belongs to a folder that matches a pattern, won't trigger services to be re-created.
The syntax is the same as `.dockerignore` file:
- `*` matches 0 or more characters in a filename.
- `?` matches a single character in filename.
- `*/*` matches two nested folders with arbitrary names
- `**` matches an arbitrary number of nested folders
If the build context includes a `.dockerignore` file, the patterns in this file is loaded as implicit content
for the `ignores` file, and values set in the Compose model are appended.
#### `include`
It is sometimes easier to select files to be watched instead of declaring those that shouldn't be watched with `ignore`.
The `include` attribute can be used to define a pattern, or a list of patterns, for paths to be considered for watching.
Only files that match these patterns will be considered when applying a watch rule. The syntax is the same as `ignore`.
```yaml
services:
backend:
image: example/backend
develop:
watch:
# rebuild image and recreate service
- path: ./src
include: *.go
action: rebuild
```
#### `path`
`path` attribute defines the path to source code (relative to the project directory) to monitor for changes. Updates to any file
inside the path, which doesn't match any `ignore` rule, triggers the configured action.
#### `target`
`target` attribute only applies when `action` is configured for `sync`. Files within `path` that have changes are synchronized with the container's filesystem, so that the latter is always running with up-to-date content.