Config for container network (#96)

Fix #66

Reviewed-on: https://gitea.com/gitea/act_runner/pulls/96
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>

config/config.example.yaml

@@ -36,3 +36,7 @@ cache:
   # The port of the cache server.
   # 0 means to use a random available port.
   port: 0
+
+container:
+  # Which network to use for the job containers.
+  network: bridge

config/config.go

@@ -28,6 +28,9 @@ type Config struct {
 		Host    string `yaml:"host"`
 		Port    uint16 `yaml:"port"`
 	} `yaml:"cache"`
+	Container struct {
+		Network string `yaml:"network"`
+	}
 }
 
 // LoadDefault returns the default configuration.
@@ -81,6 +84,9 @@ func LoadDefault(file string) (*Config, error) {
 			cfg.Cache.Dir = filepath.Join(home, ".cache", "actcache")
 		}
 	}
+	if cfg.Container.Network == "" {
+		cfg.Container.Network = "bridge"
+	}
 
 	return cfg, nil
 }