gateway: add hostname option to NewContainer API

The Meta options struct supports setting the hostname for launching
containers, however, it's only used when executing ExecOps. This patch
enables setting the hostname for the NewContainer gateway API, instead
of just the defaultHostname "buildkitsandbox".

Signed-off-by: Justin Chadwell <[email protected]>

Author: jedevc

frontend/gateway/client/client.go

@@ -38,6 +38,7 @@ type Client interface {
 // new container, without defining the initial process.
 type NewContainerRequest struct {
 	Mounts      []Mount
+	Hostname    string
 	NetMode     pb.NetMode
 	ExtraHosts  []*pb.HostIP
 	Platform    *pb.Platform

frontend/gateway/container.go

@@ -29,6 +29,7 @@ import (
 type NewContainerRequest struct {
 	ContainerID string
 	NetMode     opspb.NetMode
+	Hostname    string
 	ExtraHosts  []executor.HostIP
 	Mounts      []Mount
 	Platform    *opspb.Platform
@@ -56,6 +57,7 @@ func NewContainer(ctx context.Context, w worker.Worker, sm *session.Manager, g s
 	ctr := &gatewayContainer{
 		id:         req.ContainerID,
 		netMode:    req.NetMode,
+		hostname:   req.Hostname,
 		extraHosts: req.ExtraHosts,
 		platform:   platform,
 		executor:   w.Executor(),
@@ -280,6 +282,7 @@ func PrepareMounts(ctx context.Context, mm *mounts.MountManager, cm cache.Manage
 type gatewayContainer struct {
 	id         string
 	netMode    opspb.NetMode
+	hostname   string
 	extraHosts []executor.HostIP
 	platform   opspb.Platform
 	rootFS     executor.Mount
@@ -304,6 +307,7 @@ func (gwCtr *gatewayContainer) Start(_ context.Context, req client.StartRequest)
 			Cwd:                       req.Cwd,
 			Tty:                       req.Tty,
 			NetMode:                   gwCtr.netMode,
+			Hostname:                  gwCtr.hostname,
 			ExtraHosts:                gwCtr.extraHosts,
 			SecurityMode:              req.SecurityMode,
 			RemoveMountStubsRecursive: req.RemoveMountStubsRecursive,

frontend/gateway/forwarder/forward.go

@@ -235,6 +235,7 @@ func (c *bridgeClient) NewContainer(ctx context.Context, req client.NewContainer
 	ctrReq := gateway.NewContainerRequest{
 		ContainerID: identity.NewID(),
 		NetMode:     req.NetMode,
+		Hostname:    req.Hostname,
 		Mounts:      make([]gateway.Mount, len(req.Mounts)),
 	}
 

frontend/gateway/gateway.go

@@ -957,6 +957,7 @@ func (lbf *llbBridgeForwarder) NewContainer(ctx context.Context, in *pb.NewConta
 	ctrReq := NewContainerRequest{
 		ContainerID: in.ContainerID,
 		NetMode:     in.Network,
+		Hostname:    in.Hostname,
 		Platform:    in.Platform,
 		Constraints: in.Constraints,
 	}

frontend/gateway/grpcclient/client.go

@@ -792,6 +792,7 @@ func (c *grpcClient) NewContainer(ctx context.Context, req client.NewContainerRe
 		Constraints: req.Constraints,
 		Network:     req.NetMode,
 		ExtraHosts:  req.ExtraHosts,
+		Hostname:    req.Hostname,
 	})
 	if err != nil {
 		return nil, err

frontend/gateway/pb/gateway.pb.go

@@ -239,6 +239,7 @@ message NewContainerRequest {
 	pb.Platform platform = 4;
 	pb.WorkerConstraints constraints = 5;
 	repeated pb.HostIP extraHosts = 6;
+	string hostname = 7;
 }
 
 message NewContainerResponse{}