feat: improve Docker configuration and detection handling (#242)

- Pass `cfg` to `envcheck.CheckIfDockerRunning` function
- Add `Docker` struct to `config.go` for Docker configuration
- Update `config.example.yaml` with `docker` configuration options
- Modify `CheckIfDockerRunning` in `docker.go` to use Docker host from config if provided

Signed-off-by: appleboy <appleboy.tw@gmail.com>

Reviewed-on: https://gitea.com/gitea/act_runner/pulls/242
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Reviewed-by: wxiaoguang <wxiaoguang@noreply.gitea.com>
Co-authored-by: appleboy <appleboy.tw@gmail.com>
Co-committed-by: appleboy <appleboy.tw@gmail.com>

internal/pkg/config/config.example.yaml

@@ -68,3 +68,9 @@ container:
   # valid_volumes:
   #   - '**'
   valid_volumes: []
+
+docker:
+  # overrides the docker client host with the specified one.
+  # default value is the value of DOCKER_HOST environment variable.
+  # if DOCKER_HOST is not set, the default value is unix:///var/run/docker.sock
+  host: ""

internal/pkg/config/config.go

@@ -50,12 +50,18 @@ type Container struct {
 	ValidVolumes  []string `yaml:"valid_volumes"`  // ValidVolumes specifies the volumes (including bind mounts) can be mounted to containers.
 }
 
+// Docker represents the configuration for Docker.
+type Docker struct {
+	Host string `yaml:"host"` // Host specifies the Docker host.
+}
+
 // Config represents the overall configuration.
 type Config struct {
 	Log       Log       `yaml:"log"`       // Log represents the configuration for logging.
 	Runner    Runner    `yaml:"runner"`    // Runner represents the configuration for the runner.
 	Cache     Cache     `yaml:"cache"`     // Cache represents the configuration for caching.
 	Container Container `yaml:"container"` // Container represents the configuration for the container.
+	Docker    Docker    `yaml:"docker"`    // Docker represents the configuration for Docker.
 }
 
 // LoadDefault returns the default configuration.