From f4f7786d315beb8d7c65665b7cfc7260a988d89f Mon Sep 17 00:00:00 2001
From: Patrick <patrick@failmail.dev>
Date: Wed, 11 Dec 2024 12:56:14 +0100
Subject: [PATCH] fix: container macvlan naming

---
 nixos/extractors/nixos-container.nix | 141 +++++++++++++++------------
 1 file changed, 80 insertions(+), 61 deletions(-)

diff --git a/nixos/extractors/nixos-container.nix b/nixos/extractors/nixos-container.nix
index 10bf1e5..4a4b459 100644
--- a/nixos/extractors/nixos-container.nix
+++ b/nixos/extractors/nixos-container.nix
@@ -17,53 +17,71 @@
     warnIf
     ;
 in {
-  options.topology.extractors.nixos-container.enable = mkEnableOption "topology nixos-container extractor" // {default = true;};
+  options.topology.extractors.nixos-container.enable =
+    mkEnableOption "topology nixos-container extractor"
+    // {
+      default = true;
+    };
 
   options.containers = mkOption {
-    type = types.attrsOf (types.submodule (submod: {
-      options._nix_topology_config = mkOption {
-        type = types.unspecified;
-        internal = true;
-        default =
-          if submod.options.config.isDefined
-          then submod.config.config
-          else null;
-        description = ''
-          The configuration of the container. Defaults to `config` if that is used to define the container,
-          otherwise must be set manually to make the topology extractor work.
-        '';
-      };
-    }));
+    type = types.attrsOf (
+      types.submodule (submod: {
+        options._nix_topology_config = mkOption {
+          type = types.unspecified;
+          internal = true;
+          default =
+            if submod.options.config.isDefined
+            then submod.config.config
+            else null;
+          description = ''
+            The configuration of the container. Defaults to `config` if that is used to define the container,
+            otherwise must be set manually to make the topology extractor work.
+          '';
+        };
+      })
+    );
   };
 
   config = mkIf config.topology.extractors.nixos-container.enable {
-    topology.dependentConfigurations = map (x: x._nix_topology_config.topology.definitions or []) (attrValues config.containers);
-    topology.nodes = mkMerge (flip mapAttrsToList config.containers (
-      containerName: container: let
-        containerCfg = warnIf (container._nix_topology_config == null) "topology: The nixos container ${containerName} uses `path` instead of `config`. Please set _nix_topology_config to the `.config` of its nixosSystem instanciation to allow nix-topology to access the configuration." container._nix_topology_config;
-      in
-        optionalAttrs (containerCfg != null && containerCfg ? topology) {
-          ${containerCfg.topology.id} = {
-            guestType = "nixos-container";
-            parent = config.topology.id;
+    topology.dependentConfigurations = map (x: x._nix_topology_config.topology.definitions or []) (
+      attrValues config.containers
+    );
+    topology.nodes = mkMerge (
+      flip mapAttrsToList config.containers (
+        containerName: container: let
+          containerCfg =
+            warnIf (container._nix_topology_config == null)
+            "topology: The nixos container ${containerName} uses `path` instead of `config`. Please set _nix_topology_config to the `.config` of its nixosSystem instanciation to allow nix-topology to access the configuration."
+            container._nix_topology_config;
+        in
+          optionalAttrs (containerCfg != null && containerCfg ? topology) {
+            ${containerCfg.topology.id} = {
+              guestType = "nixos-container";
+              parent = config.topology.id;
 
-            interfaces = mkMerge (
-              flip map container.macvlans (
-                i: {
-                  ${i} = {
-                    type = "macvlan";
-                    physicalConnections = [
-                      {
-                        node = config.topology.id;
-                        interface = i;
-                        renderer.reverse = true;
-                      }
-                    ];
-                  };
-                }
-              )
-              ++ flip map container.interfaces (
-                i: {
+              interfaces = mkMerge (
+                flip map container.macvlans (
+                  i: let
+                    splitString = lib.splitString ":" i;
+                    iface_host = lib.elemAt splitString 0;
+                    iface_container =
+                      if lib.length splitString > 1
+                      then lib.elemAt splitString 1
+                      else "mv-" + iface_host;
+                  in {
+                    ${iface_container} = {
+                      type = "macvlan";
+                      physicalConnections = [
+                        {
+                          node = config.topology.id;
+                          interface = iface_host;
+                          renderer.reverse = true;
+                        }
+                      ];
+                    };
+                  }
+                )
+                ++ flip map container.interfaces (i: {
                   ${i} = {
                     type = let
                       t = config.topology.nodes.${config.topology.id}.interfaces.${i}.type or null;
@@ -77,27 +95,28 @@ in {
                       }
                     ];
                   };
-                }
-              )
-            );
-          };
+                })
+              );
+            };
 
-          # Add interfaces to host
-          ${config.topology.id} = {
-            interfaces = mkMerge (
-              flip map container.macvlans (
-                i: {
-                  ${i} = {};
-                }
-              )
-              ++ flip map container.interfaces (
-                i: {
+            # Add interfaces to host
+            ${config.topology.id} = {
+              interfaces = mkMerge (
+                flip map container.macvlans (
+                  i: let
+                    splitString = lib.splitString ":" i;
+                    iface_host = lib.elemAt splitString 0;
+                  in {
+                    ${iface_host} = {};
+                  }
+                )
+                ++ flip map container.interfaces (i: {
                   ${i} = {};
-                }
-              )
-            );
-          };
-        }
-    ));
+                })
+              );
+            };
+          }
+      )
+    );
   };
 }