Step 2 - Build your own Director


The Director is a backend component in the Online Game Service that typically performs the following tasks:

  • Fetch Matches from Open Match for each MatchProfile.
  • Fetch game allocations from a DGS (Dedicated Game Server) system.
  • Establish connections from players to game servers and set Assignments based on connections in Open Match.

The tutorial provides a very basic Director scaffold $TUTORIALROOT/director that generates some MatchProfiles and then call FetchMatches for these profiles from Open Match. The director then sets Assignment to a fake connection string to simulate a DGS allocation for every Ticket in a generated match.

pb.Match pb.MatchProfile pb.FunctionConfig backend.AssignTickets backend.FetchMatches

Make Changes

The Director uses a helper function generateProfiles() in $TUTORIALROOT/director/profile.go to generate MatchProfiles. For this tutorial, we will generate a MatchProfile for each game-mode. The MatchProfile will have a single Pool that has a single filtering criterion searching for the desired game-mode. Director will call FetchMatches for each of the generated Profiles. Below is a sample snippet to achieve this:

func generateProfiles() []*pb.MatchProfile {
  var profiles []*pb.MatchProfile
  modes := []string{"mode.demo", "mode.ctf", "mode.battleroyale"}
  for _, mode := range modes {
    profiles = append(profiles, &pb.MatchProfile{
      Name: "mode_based_profile_" + mode,
      Pools: []*pb.Pool{
          Name: "pool_mode_" + mode,
          TagPresentFilters: []*pb.TagPresentFilter{
              Tag: mode,

  return profiles

Please copy the above helper or add your own profile generation logic to $TUTORIALROOT/director/profiles.go. Also, you may tweak the profile polling interval, Assignment logic, etc. in $TUTORIALROOT/director/main.go.


The following values need to be changed if your setup is different from the default in the TUTORIALROOT/director/main.go. The default value assumes you have Open Match deployed under open-match namespace and the Game Frontend under mm101-tutorial namespace in the same cluster:

omBackendEndpoint - Open Match Backend endpoint

functionHostName - Kubernetes Internal Hostname of your Match Function

functionPort - Port Number that you host your Match Function service on

Build and Push

Now that you have customized the Director, please run the below commands from $TUTORIALROOT to build a new image and push it to your configured image registry.

# Build the Director image.
docker build -t $REGISTRY/mm101-tutorial-director director/

# Push the Director image to the configured Registry.
docker push $REGISTRY/mm101-tutorial-director

What’s Next

Let’s proceed to build the Match Function.

Last modified October 11, 2022