[container-run-create]: add support for --network none (apple#739)

Closes apple#386

Author: saehejkang

Sources/ContainerClient/Core/ClientNetwork.swift

@@ -24,6 +24,7 @@ public struct ClientNetwork {
     static let serviceIdentifier = "com.apple.container.apiserver"
 
     public static let defaultNetworkName = "default"
+    public static let noNetworkName = "none"
 }
 
 extension ClientNetwork {

Sources/ContainerClient/Utility.swift

@@ -176,11 +176,18 @@ public struct Utility {
 
         config.virtualization = management.virtualization
 
-        config.networks = try getAttachmentConfigurations(containerId: config.id, networkIds: management.networks)
-        for attachmentConfiguration in config.networks {
-            let network: NetworkState = try await ClientNetwork.get(id: attachmentConfiguration.network)
-            guard case .running(_, _) = network else {
-                throw ContainerizationError(.invalidState, message: "network \(attachmentConfiguration.network) is not running")
+        if management.networks.contains(ClientNetwork.noNetworkName) {
+            guard management.networks.count == 1 else {
+                throw ContainerizationError(.unsupported, message: "no other networks may be created along with network \(ClientNetwork.noNetworkName)")
+            }
+            config.networks = []
+        } else {
+            config.networks = try getAttachmentConfigurations(containerId: config.id, networkIds: management.networks)
+            for attachmentConfiguration in config.networks {
+                let network: NetworkState = try await ClientNetwork.get(id: attachmentConfiguration.network)
+                guard case .running(_, _) = network else {
+                    throw ContainerizationError(.invalidState, message: "network \(attachmentConfiguration.network) is not running")
+                }
             }
         }
 

Sources/Services/ContainerAPIService/Networks/NetworksService.swift

@@ -107,6 +107,11 @@ public actor NetworksService {
                 "id": "\(configuration.id)"
             ])
 
+        //Ensure that the network is not named "none"
+        if configuration.id == ClientNetwork.noNetworkName {
+            throw ContainerizationError(.unsupported, message: "network \(configuration.id) is not a valid name")
+        }
+
         // Ensure nobody is manipulating the network already.
         guard !busyNetworks.contains(configuration.id) else {
             throw ContainerizationError(.exists, message: "network \(configuration.id) has a pending operation")