(rootful) docker-compose now updates network MTU

Previously, the following network block did not update using
docker-compose:

```
networks:
  default:
    driver: bridge
    driver_opts:
      mtu: 9000
```

In the API, the network options were previously not being handled when the
network was being created. I translated the docker options into podman
options, and added the options to the network.

When doing `podman network inspect <network>`, the results now contain
`"mtu": "9000"`

Fixes: #14482

Signed-off-by: Jake Correnti <jcorrenti13@gmail.com>

3 files changed, 76 insertions, 6 deletions

diff --git a/pkg/api/handlers/compat/networks.go b/pkg/api/handlers/compat/networks.go
index 6fdd5c6a7..9da21d15f 100644
--- a/pkg/api/handlers/compat/networks.go
+++ b/pkg/api/handlers/compat/networks.go
@@ -161,8 +161,9 @@ func ListNetworks(w http.ResponseWriter, r *http.Request) {
 
 func CreateNetwork(w http.ResponseWriter, r *http.Request) {
 	var (
-		networkCreate types.NetworkCreateRequest
-		network       nettypes.Network
+		networkCreate   types.NetworkCreateRequest
+		network         nettypes.Network
+		responseWarning string
 	)
 	runtime := r.Context().Value(api.RuntimeKey).(*libpod.Runtime)
 	if err := json.NewDecoder(r.Body).Decode(&networkCreate); err != nil {
@@ -179,8 +180,40 @@ func CreateNetwork(w http.ResponseWriter, r *http.Request) {
 	network.Internal = networkCreate.Internal
 	network.IPv6Enabled = networkCreate.EnableIPv6
 
-	// FIXME use docker options and convert them to valid libpod options
-	// network.Options = networkCreate.Options
+	network.Options = make(map[string]string)
+
+	// TODO: we should consider making this constants in c/common/libnetwork/types
+	for opt, optVal := range networkCreate.Options {
+		switch opt {
+		case "mtu":
+			fallthrough
+		case "com.docker.network.driver.mtu":
+			if network.Driver == nettypes.BridgeNetworkDriver {
+				network.Options["mtu"] = optVal
+			}
+		case "icc":
+			fallthrough
+		case "com.docker.network.bridge.enable_icc":
+			// TODO: needs to be implemented
+			if network.Driver == nettypes.BridgeNetworkDriver {
+				responseWarning = "com.docker.network.bridge.enable_icc is not currently implemented"
+			}
+		case "com.docker.network.bridge.name":
+			if network.Driver == nettypes.BridgeNetworkDriver {
+				network.NetworkInterface = optVal
+			}
+		case "mode":
+			if network.Driver == nettypes.MacVLANNetworkDriver || network.Driver == nettypes.IPVLANNetworkDriver {
+				network.Options[opt] = optVal
+			}
+		case "parent":
+			if network.Driver == nettypes.MacVLANNetworkDriver || network.Driver == nettypes.IPVLANNetworkDriver {
+				network.NetworkInterface = optVal
+			}
+		default:
+			responseWarning = "\"" + opt + ": " + optVal + "\" is not a recognized option"
+		}
+	}
 
 	// dns is only enabled for the bridge driver
 	if network.Driver == nettypes.BridgeNetworkDriver {
@@ -242,9 +275,10 @@ func CreateNetwork(w http.ResponseWriter, r *http.Request) {
 
 	body := struct {
 		ID      string `json:"Id"`
-		Warning string
+		Warning string `json:"Warning"`
 	}{
-		ID: newNetwork.ID,
+		ID:      newNetwork.ID,
+		Warning: responseWarning,
 	}
 	utils.WriteResponse(w, http.StatusCreated, body)
 }
diff --git a/test/compose/update_network_mtu/docker-compose.yml b/test/compose/update_network_mtu/docker-compose.yml
new file mode 100644
index 000000000..fabd7b4f2
--- /dev/null
+++ b/test/compose/update_network_mtu/docker-compose.yml
@@ -0,0 +1,26 @@
+version: '3.7'
+
+services:
+  nginx:
+    image: alpine
+    ports:
+      - 8000:5000
+    networks:
+      - default
+      - macvlan_net
+
+networks:
+  default:
+    driver: bridge
+    driver_opts:
+      com.docker.network.bridge.name: docker0
+      com.docker.network.driver.mtu: 9000
+  macvlan_net:
+    driver: macvlan
+    driver_opts:
+      mode: bridge
+    ipam:
+      config:
+        -
+          subnet: 192.168.20.0/24
+          gateway: 192.168.20.1
diff --git a/test/compose/update_network_mtu/tests.sh b/test/compose/update_network_mtu/tests.sh
new file mode 100644
index 000000000..57411eb34
--- /dev/null
+++ b/test/compose/update_network_mtu/tests.sh
@@ -0,0 +1,10 @@
+# -*- bash -*-
+
+podman network inspect --format='{{ range . }} {{ .Options.mtu }} {{ end }}' update_network_mtu_default
+like "$output" "9000" "$testname : network mtu is set"
+
+podman network inspect --format='{{ range . }} {{ .NetworkInterface }} {{ end }}' update_network_mtu_default
+like "$output" "docker0" "$testname: network interface is set"
+
+podman network inspect --format='{{ range . }} {{ .Options.mode }} {{ end }}' update_network_mtu_macvlan_net
+like "$output" "bridge" "$testname : network mode is set"